Chapter 1 — GENERAL CODE PROVISIONS

(Matrix Adoption Tables are non-regulatory, intended only as an aid to the user. See Chapter 1 for state agency authority and building application.)

Adopt the entire UMC chapter as amended, state-amended sections are listed below: If there is an “X” under a particular state agency’s acronym in this row, it means that a particular state agency has adopted the entire model code chapter, with state amendments.

Each section that a state agency has amended and/or added within a particular chapter is listed. There will be an “X” under the agency’s acronym in the row of the amended and/or added section.

Example:

CALIFORNIA MECHANICAL CODE – MATRIX ADOPTION TABLE

CHAPTER 1 - GENERAL CODE PROVISIONS

(Matrix Adoption Tables are non-regulatory, intended only as an aid to the user. See Chapter 1 for state agency authority and building application.)

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Adopt only those sections which are listed below:

If there is an “X” under a particular state agency’s acronym in this row, it means that particular state agency is adopting only specific model code or state-amended sections within this chapter. There will be an “X” in the column under the agency’s acronym, as well as an “X” by each section that the agency has adopted.

Example:

CALIFORNIA MECHANICAL CODE – MATRIX ADOPTION TABLE

CHAPTER 1 - GENERAL CODE PROVISIONS

(Matrix Adoption Tables are non-regulatory, intended only as an aid to the user. See Chapter 1 for state agency authority and building application.)

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HOW TO DISTINGUISH MODEL CODE LANGUAGE FROM CALIFORNIA AMENDMENTS

To distinguish between model code language and incorporated California Amendments, including exclusive California standards, California amendments will appear in italics font print.

Symbols in the margins indicate the status of code changes as follows:

[BSC]

This symbol identifies which State agency(s) by its “acronym” that has amended a section of the model code. For a complete listing of State agency acronyms, see the Application Section within Chapter 1, Division I.

This symbol indicates that a change has been made to a California amendment.

This symbol indicates that a section, paragraph, or table has been revised or relocated within IAPMO model code language.

This symbol indicates deletion of California language.

This symbol indicates where an entire section, paragraph, or table has been deleted from IAPMO model code language.

Revision Markings A double right angle ( « ) in the margin indicates that the text or a table has been relocated within the code.

TIA TIA TIA TIA

TIA indicates that the revision is the result of a Tentative Interim Amendment.

For further information on tentative interim amendments see Section 5 of the IAPMO Regulations Governing Committee Projects available at http://codes.iapmo.org/

A reference in brackets [ ] following a section or paragraph indicates material that has been extracted from another document. This reprinted material is not the complete and official position of the source document on the referenced subject that is represented by the standard in its entirety. Material contained in this document that is taken or extracted from NFPA standards is used with permission of the National Fire Protection Association. This material is not the complete and official position of the NFPA on the reference subject, which is represented solely by the relevant standard in its entirety. NFPA standards can be accessed at www.nfpa.org. In addition, this extracted material may include revisions or modifications developed through IAPMO’s standards development process. Therefore, NFPA disclaims responsibility for the content of this Code.

Text that is extracted pursuant to IAPMO’s Extract Guidelines, but outside of the regular revision process is denoted with the use of the source document in the margin. This text is not fully processed by IAPMO in accordance with ANSI’s public announcement consensus requirements for an American National Standard (ANS) nor approved by ANSI’s Board of Standards Review. The next revision cycle processes such text in accordance with those requirements.

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Important Notices and Disclaimers The 2024 edition of the Uniform Mechanical Code is developed through a consensus standards development process approved by the American National Standards Institute. This process brings together volunteers representing varied viewpoints and interests to achieve consensus on mechanical issues. While the International Association of Plumbing and Mechanical Officials (IAPMO) administers the process and establishes rules to promote fairness in the development of consensus, it does not independently test, evaluate, or verify the accuracy of any information or the soundness of any judgments contained in its codes

and standards.

IAPMO disclaims liability for any personal injury, property, or other damages of any nature whatsoever, whether special, indirect, consequential, or compensatory, directly or indirectly resulting from the publication, use of, or reliance on this document. IAPMO also makes no guarantee or warranty as to the accuracy or completeness of any information published

herein.

In issuing and making this document available, IAPMO is not undertaking to render professional or other services for or on behalf of any person or entity. Nor is IAPMO undertaking to perform any duty owed by any person or entity to someone else. Anyone using this document should rely on his or her own independent judgment or, as appropriate, seek the advice of a competent professional in determining the exercise of reasonable care in any given circumstances.

dertaking to render professional or other services for or on behalf of any person or entity. Nor is IAPMO undertaking to perform any duty owed by any person or entity to someone else. Anyone using this document should rely on his or her own independent judgment or, as appropriate, seek the advice of a competent professional in determining the exercise of reasonable care in any given circumstances.

Updating IAPMO Codes Users of IAPMO codes should be aware that IAPMO codes may be amended from time to time through the issuance of Tentative Interim Amendments or corrected by Errata. IAPMO codes consist of the current edition of the document together with any Tentative Interim Amendments and any Errata in effect.

To access information for a specific code or to determine whether an IAPMO code has been amended through the issuance of Tentative Interim Amendments or corrected by Errata, please visit the IAPMO codes information page on the IAPMO’s website (https://www.iapmo.org/code-development). The codes information page provides a list of IAPMO codes with up-to-date specific information including any issued Tentative Interim

Amendments and Errata.

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FOREWORD

Origin and Development The industry has long recognized the advantages of a statewide adopted mechanical code. The first edition of the Uniform Mechanical Code [®] (UMC [®] ) was adopted by IAPMO in 1967. The widespread use of this code over the past five decades by jurisdictions throughout the United States and internationally is testament to its merit.

Publishing of the 2003 Uniform Mechanical Code was a significant milestone because it was the first time in the history of the United States a mechanical code was developed through a true consensus process. The 2024 edition represents the most current approaches in the mechanical field and is the eighth edition developed under the ANSI consensus process. Contributions to the content of this code consists of diverse interests as consumers, enforcing authorities, installers/maintainers, labor, manufacturers, research/standards/testing laboratories, special experts, and users.

The Uniform Mechanical Code provides consumers with complete requirements for the installation and maintenance of heating, ventilating, cooling, and refrigeration systems, while, at the same time, allowing latitude for innovation and new technologies. The public at large is invited and encouraged to take part in IAPMO’s open consensus code development process. This code is updated every three years. The Uniform Mechanical Code is dedicated to all those who, in working to achieve “the ultimate mechanical code,” have unselfishly devoted their time, effort, and personal funds to create and maintain this, the finest mechanical code in existence today.

The Uniform Mechanical Code updates every three years in revision cycles that begin twice each year that takes two years to complete.

Each revision cycle advances according to a published schedule that includes final dates for all major events and contains four basic steps as follows:

1. Proposal Stage;
2. Comment Stage;
3. Association Technical Meeting;
4. Council Appeals and Issuance of Code.

IAPMO develops “full consensus” codes built on a foundation of maximum participation and agreement by a broad range of interests. This philosophy has led to producing technically sound codes that promote health and safety, yet do not stifle design or development.

It is important to stress that the process remains committed to the principles of consensus code development where consensus Technical Committees and Correlating Committees revise codes. The public and membership are offered multiple opportunities to debate, provide input and raise concerns through Amending Motions at the annual Assembly Consideration Session. Anyone may submit an appeal related to the issuance of a document through the IAPMO Standards Council.

The 2024 Uniform Mechanical Code is supported by the Mechanical Contractors Association of America (MCAA), the Plumbing-Heating-Cooling Contractors National Association (PHCC-NA), the United Association (UA), and the World Plumbing Council (WPC). The presence of these logos, while reflecting support, does not imply any ownership of the copyright to the UMC, which is held exclusively by IAPMO. Further, the logos of these associations indicate the support of IAPMO’s open consensus process being used to develop IAPMO’s codes and standards.

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FOREWORD

The addresses of the organizations are as follows: ASSE – 18927 Hickory Creek Drive, Suite 220 • Mokena, IL 60448 • (708) 995-3019 MCAA – 1385 Piccard Drive • Rockville, MD 20850 • (301) 869-5800 PHCC-NA – 180 S Washington Street, Suite 100 • Falls Church, VA 22040-6808 • (800) 533-7694 RPA – 18927 Hickory Creek Drive, Suite 220 • Mokena, IL 60448 • (877) 427-6601 UA – Three Park Place • Annapolis, MD 21401 • (410) 269-2000 WPC – Auf der Mauer 11 • 8021 Zurich, Switzerland • Secretariat@worldplumbing.org

Adoption The Uniform Mechanical Code is available for adoption and use by jurisdictions in the United States and Internationally. Its use within a governmental jurisdiction is accomplished through adoption by reference in accordance with applicable jurisdictional laws. At adoption, jurisdictions should insert the applicable information in bracketed words in the sample ordinance. The sample legislation for adoption of the Uniform Mechanical Code on page ix provides key components, regulations and resolutions.

Revision Markings Solid vertical lines in the margins indicate a technical change from the requirements of the 2021 edition. An arrow ( ) in the margin indicates where an entire section, paragraph, exception, figure, or table has been deleted, or an item in a list of items or a table has been deleted.

A double right angle ( « ) in the margin indicates that the text, table, or figure has been relocated within the code. The table found on page xxi points out the relocations in the 2024 edition of the Uniform Mechanical Code .

TIA TIA indicates that the revision is the result of a Tentative Interim Amendment. TIA For further information on tentative interim amendments see Section 5 of the IAPMO TIA TIA Regulations Governing Committee Projects available at http://www.iapmo.org/code**TIA** development

A reference in brackets [ ] following a section or paragraph indicates material that has been extracted from another document. A reference in brackets { } following a section or paragraph indicates material that has been extracted from another document and has been modified further by the Technical Committee. This reprinted material is not the complete and official position of the source document on the referenced subject that is represented by the standard in its entirety. Material contained in this document that is taken or extracted from NFPA standards is used with permission of the National Fire Protection Association. This material is not the complete and official position of the NFPA on the reference subject, which is represented solely by the relevant standard in its entirety. NFPA standards can be accessed at www.nfpa.org. In addition, this extracted material may include revisions or modifications developed through IAPMO’s standards development process. Therefore, NFPA disclaims responsibility for the content of this code.

Text that is extracted pursuant to IAPMO’s Extract Guidelines, but outside of the regular revision process is denoted with the use of the source document in the margin. This text is not fully processed by IAPMO in accordance with ANSI’s public announcement consensus requirements for an American National Standard (ANS) nor approved by ANSI’s Board of Standards Review. The next revision cycle processes such text in accordance with those requirements.

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FORMAT OF THE UNIFORM MECHANICAL CODE

The format of the Uniform Mechanical Code (UMC) arranges each chapter in accordance with a specific subject matter. However, Chapter 3 is dedicated to general requirements that are applicable to every chapter. The subject matters are divided as follows:

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FORMAT OF THE UNIFORM MECHANICAL CODE

The following is a summary of the scope and intent of the provisions addressed within the chapters and appendices of the Uniform Mechanical Code :

Chapter 1 Administration. Chapter 1 regulates the application, enforcement, and administration of subsequent requirements of the code. As well as establishing the scope of the code, this chapter is concerned with enforcing the requirements contained in the body of the code. A mechanical code, as with any other code, is intended to be adopted as a legally enforceable document to safeguard health, safety, property, and public welfare. The code cannot be effective without satisfactory provisions for its administration and enforcement. The Authority Having Jurisdiction is to review the proposed and completed work and decide whether a mechanical system conforms to the code requirements. As a public servant, the Authority Having Jurisdiction enforces the code in an unbiased proper manner. The design professional is responsible for the design of a safe mechanical system. The contractor is responsible for installing the system in accordance with the plans.

Chapter 2 Definitions. To maintain consistency and encourage the use of common terminology, Chapter 2 establishes definitions to provide clarity of terms and promote the use of a common language throughout the code. Understanding definitions within the context of their application enables greater collaboration, efficiency, standardization, and interpretation in applying and enforcing terms used throughout the code. Codes are technical documents, and every term can impact the meaning of the code text. Terms not defined have a normally accepted meaning.

promote the use of a common language throughout the code. Understanding definitions within the context of their application enables greater collaboration, efficiency, standardization, and interpretation in applying and enforcing terms used throughout the code. Codes are technical documents, and every term can impact the meaning of the code text. Terms not defined have a normally accepted meaning.

Chapter 3 General Regulations. Chapter 3 regulates the general requirements, not specific to other chapters, for installing mechanical systems. Many regulations are not specific mechanical requirements but relate to the overall mechanical system. This chapter contains safety requirements for appliance location and installation, appliance and system access, condensate disposal, clearances to combustibles, and return or outside air used in mechanical systems. Listing method of approval, based on applicable nationally recognized standards for the safe and proper installation of mechanical systems, is essential to ensure protection of public health, safety, and welfare. These safety requirements provide protection for piping, tubing, materials, and structures, including provisions for installation practices addressing stress and strain, sleeving, and hanger support. The building’s structural stability is protected by the regulations for cutting and notching of structural members.

Chapter 4 Ventilation Air. Chapter 4 regulates the minimum requirements for ventilation air supply, exhaust, and makeup air for occupiable spaces within a building. Building ventilation is one important factor affecting the relationship between airborne transmission of respiratory infections and the health and productivity of workers. Ventilation air may be composed of mechanical or natural ventilation, infiltration, recirculated air, transfer air, or a suitable combination of these. Providing a comfortable and healthy indoor environment for building occupants is of primary concern. When determining ventilation rates, typical and unusual significant sources of indoor pollution need to be controlled. Areas such as kitchens, bathrooms, and laundries are all built to allow specific functions. These spaces produce pollutants such as moisture, odors, volatile organic compounds, particles, or combustion byproducts. The purpose of local exhaust is to control concentrates of these pollutants in the room into which they were emitted and to reduce the spread of pollutants into other parts of the occupancy. Local exhaust ventilation is the source control for pollution that is expected in certain rooms. Using local exhaust to extract contaminants before they mix with the indoor environment is essential.

yproducts. The purpose of local exhaust is to control concentrates of these pollutants in the room into which they were emitted and to reduce the spread of pollutants into other parts of the occupancy. Local exhaust ventilation is the source control for pollution that is expected in certain rooms. Using local exhaust to extract contaminants before they mix with the indoor environment is essential.

Chapter 5 Exhaust Systems. Chapter 5 regulates the minimum requirements for exhaust systems. Chapter 5 contains two parts: Part I provides exhaust requirements for environmental air ducts and product conveying systems; Part II provides exhaust requirements for commercial hoods and kitchen ventilation. Environmental air ducts include exhaust ducts used for transporting the air from domestic kitchens, bathrooms, shower rooms, locker rooms, janitor’s closets, and clothes dryers. Systems that carry nonabrasive exhaust, such as smoke, moderate abrasives such as sawdust, and high abrasives such as manganese or acid vapors use product-conveying ducts. Part II provides the minimum fire safety requirements related to the design, installation, inspection, and maintenance of grease-type operations, such as cooking, for both fuel-gas and solid fuel. Cooking produces a significant amount of smoke, fumes, vapors, heat, and other pollutants. Therefore, acceptable kitchen ventilation is necessary to prevent fires from the build-up of grease and to provide the occupants protection from smoke, unpleasant odors, pollutants, and dangerous gases. There are two types of exhaust hoods (Type I and Type II) used in commercial kitchen applications.

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FORMAT OF THE UNIFORM MECHANICAL CODE

Type I hoods are intended to be installed above equipment or appliances that generate grease or smoke. Type II hoods are intended to be installed above equipment or appliances that generate steam, vapor, heat, or odors and do not generate grease or smoke.

Chapter 6 Duct Systems. Chapter 6 regulates requirements for ducts and plenums that are portions of a heating, cooling, ventilation, or exhaust system. This chapter contains material and installation requirements for metal, gypsum, factory-made, flexible, and plastic ducts. It also contains provisions for duct insulation, dampers, fire protection, and automatic shutoff for the building’s air distribution system. It is worth noting that exhaust ducts are regulated by Chapter 5, and combustion air ducts are regulated by Chapter 7.

r exhaust system. This chapter contains material and installation requirements for metal, gypsum, factory-made, flexible, and plastic ducts. It also contains provisions for duct insulation, dampers, fire protection, and automatic shutoff for the building’s air distribution system. It is worth noting that exhaust ducts are regulated by Chapter 5, and combustion air ducts are regulated by Chapter 7.

Chapter 7 Combustion Air. Chapter 7 regulates combustion air requirements for ventilation and dilution of flue gases for appliances installed in buildings. Fuel-gas appliances not regulated by chapter include direct vent appliances and Type I clothes dryers. Makeup air requirements for Type I clothes dryers are located in Chapter 5. Chapter 7 provides acceptable methods for supplying satisfactory combustion air to ensure proper combustion. Combustion air can be supplied by using indoor combustion air or by introducing the air from the outdoors.

Combustion is the rapid oxidation of fuel to release energy. The oxygen required to release the energy from the fuel normally comes from the air. Incomplete combustion of fuel occurs when inadequate oxygen is provided to the appliance. Combustion is needed to provide ventilation cooling for the casing and internal controls. When a lack of oxygen occurs, some of the carbon is not oxidized, and carbon monoxide forms.

Chapter 8 Chimneys and Vents. Chapter 8 regulates the installation, design, and construction of venting systems for fuel-burning appliances. The provisions addressed within this chapter follow procedures an installer would use to design or evaluate a venting system. Many requirements apply to the design and construction of venting systems, chimneys, installation of gas vents, and the sizing of venting system for a Category I appliance. Sizing venting systems require rigorous engineering calculations. However, the venting sizing requirements and sizing tables in this chapter already perform the calculations for the benefit of the end user.

Combustion appliances produce products of incomplete combustion, including potentially harmful carbon monoxide (CO). It is desirable to vent these products to the outdoors. Although the gas is clean-burning fuel, the products of combustion must not be allowed to collect within a building.

Chapter 9 Installation of Specific Appliances. Chapter 9 regulates the minimum requirements for the design, construction and installation of specific appliances. The provisions address the minimum requirements for gas-fired appliances, oil-fired appliances, wood-fired appliances, and electric-type appliances. In addition to the requirements of this chapter, appliances are also required to comply with the general requirements of Chapter 3.

s.** Chapter 9 regulates the minimum requirements for the design, construction and installation of specific appliances. The provisions address the minimum requirements for gas-fired appliances, oil-fired appliances, wood-fired appliances, and electric-type appliances. In addition to the requirements of this chapter, appliances are also required to comply with the general requirements of Chapter 3.

Chapter 10 Boilers and Pressure Vessels. Chapter 10 regulates the construction, installation, operation, repair, and alteration of boilers and pressure vessels. The safety provisions within this chapter address controls and limit devices for automatic boilers, methods of determining expansion tank capacities, discharge piping, relief valves, shutoff valves, gas-pressure and combustion regulators, and inspections and tests. Potable water heaters are free from the requirements of Chapter 10 as they are within the scope of the Uniform Plumbing Code (UPC).

Pressure vessels store large amounts of energy and must comply with ASME Boiler and Pressure Vessel Code (BPVC) Section VIII.1. The stored energy must be contained to prevent disastrous failures. Boilers must comply with ASME BPVC Section I, ASME BPVC Section IV, or NFPA 85. Installing a safety relief valve and expansion tank prevents pressures in the tank from exceeding the design threshold.

Chapter 11 Refrigeration. Chapter 11 regulates the design, installation, and construction requirements of refrigeration systems and the installation and construction of cooling towers. Refrigeration is a method used for achieving heat transfer to cool spaces. Refrigerants are the most common medium used to transfer the heat energy from the low-temperature level to the high-temperature level. Table

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FORMAT OF THE UNIFORM MECHANICAL CODE

1102.3 lists the most commonly used refrigerants and is labeled by a number. The concentration limits provided in Table 1102.3 are useful for the quantity of refrigerant required to cool a volume of space safely.

A major milestone reached in the industry was the introduction of lower flammability refrigerants such as A2L and B2L. The industry’s concerns to address lower Global Warming Potential (GWP) refrigerants led to the development of these lower flammability refrigerants. Chapter 11 does not only include these lower flammability refrigerants in Table 1102.3, but it also contains specific A2L and B2L provisions to address the precautions necessary for the proper use of these products. In particular, high-probability systems using A2L refrigerants for human comfort applications are covered by provisions which include refrigerant concentration limits, mechanical ventilation, ignition sources, compressors and pressure vessels, and refrigerant sensors.

.3, but it also contains specific A2L and B2L provisions to address the precautions necessary for the proper use of these products. In particular, high-probability systems using A2L refrigerants for human comfort applications are covered by provisions which include refrigerant concentration limits, mechanical ventilation, ignition sources, compressors and pressure vessels, and refrigerant sensors.

In addition, Chapter 11 addresses other minimum requirements for refrigeration systems such as refrigeration machinery rooms (including ventilation), relief valves, and pressure vessels. Apart from refrigerants, the chapter also addresses minimum requirements for systems that use other mediums such as ammonia and brine systems. For ammonia systems, such systems are required to comply with IIAR 2, IIAR 3, IIAR/ANSI 4, IIAR 5, and IIAR 6.

Chapter 12 Hydronics. Chapter 12 regulates hydronic systems that are part of heating, cooling, ventilation, and conditioning systems. Such piping systems include steam, hot water, radiant heating and cooling, chilled water, steam condensate, condenser water, ground source heat pump systems, snow and ice melt systems, ambient temperature loops, and district ambient temperature loops. Provisions within this chapter addressing ground source heat pumps and ambient temperature loops apply to the hydronic portions of the system. Geothermal energy systems, including ground source heat pumps and ambient temperature loops, are regulated by Chapter 17.

Materials for piping and tubing must meet the working temperature and pressure of the system. In addition, materials must be compatible with the transfer medium to prevent deformation, bursting, or any chemical action between the material and the transfer medium. The allowable joining methods for piping or tubing are provided for application and enforcement purposes.

Chapter 13 Fuel Gas Piping. Chapter 13 regulates gas piping systems in a building, structure or within the property lines of buildings up to 5 psi. Gas piping systems must supply the minimum volume of gas required by each gas appliance to perform their proper operation under working conditions without exceeding the maximum pressure specified by each manufacturer. Because of the hazards associated with fuel gas, it is important to ensure the gas system has been inspected and tested, and that it is safe to turn on the gas supply to the building.

Chapter 14 Process Piping. Chapter 14 regulates process piping that typically is found in refineries. Process piping is considered the piping or tubing portion that transports liquid or gas, which is used directly in research, laboratory, or production process. This chapter may be used with another chapter of the code. For example, refrigeration piping, fuel gas piping, or fuel oil piping may need to comply with this chapter for process piping and the applicable chapter for materials, design, and installation.

g is considered the piping or tubing portion that transports liquid or gas, which is used directly in research, laboratory, or production process. This chapter may be used with another chapter of the code. For example, refrigeration piping, fuel gas piping, or fuel oil piping may need to comply with this chapter for process piping and the applicable chapter for materials, design, and installation.

Chapter 15 Solar Energy Systems. Chapter 15 refers the user to the Uniform Solar, Hydronics and Geothermal Code (USHGC) for solar energy system requirements. The USHGC contains comprehensive design, installation, and construction requirements for all types of solar thermal systems, such as drainback, thermosiphon, open-loop, and closed-loop systems. The USHGC also addresses installation of solar photovoltaic (PV) systems including array circuit(s), inverter(s), and controller(s) for such systems.

Chapter 16 Stationary Power Plants. This chapter provides minimum requirements for stationary fuel cell power plants. A fuel cell is a device that produces electricity by a chemical reaction. Fuel cells have been used mostly for satellites. However, the costs of fuel cells have decreased to a point where they are now economically attainable. With the increase in electricity costs, fuel cells are being considered as an alternative for producing electricity.

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FORMAT OF THE UNIFORM MECHANICAL CODE

Chapter 17 Geothermal Energy Systems and Ambient Temperature Loops. Chapter 17 regulates the design, installation, construction, and location of geothermal energy systems and ambient temperature loops (ATLs). This chapter provides the minimum safety requirements for various types of geothermal systems, including building systems coupled with a ground-heat exchangers, submerged heat exchangers using water-based fluid as a heat transfer medium, and groundwater (well). For ease of use and clarification on the applicability of geothermal provisions, Chapter 17 is divided into five parts pertaining to general provisions for all types of geothermal systems, closed-loop systems, open-loop systems, direct-exchange (DX) systems, and ambient temperature loops. For district ambient temperature loops, including those utilizing multiple hybrid systems, Part I through Part V are applicable.

In order to properly design a geothermal system, it is important to know the seasonal variation in the soil temperature, as well as the soil’s inherent capability to store and transmit heat, namely its heat capacity and thermal conductivity. In addition, a properly designed heat pump distribution system is essential for the distribution of geothermal energy.

Materials for piping and tubing must meet the working temperature and pressure of the system. Furthermore, materials must be compatible with the transfer medium to prevent deformation, bursting, or any chemical action between the material and the transfer medium. Approved materials for indoor piping, fittings, and accessories that are a part of a groundwater system as well as the allowable joining methods for piping or tubing are provided for application and enforcement purposes.

Chapter 18 Referenced Standards. Chapter 18 provides two comprehensive tables with referenced standards. The standards listed in Table 1801.1 are applied as indicated in the applicable reference section(s). A list of additional approved standards, publications, practices, and guides that are not referenced in specific sections appear in Table 1801.2.

Referenced standards set forth specific details of accepted practices, materials specifications, or test methods in many specialized applications. Standards provide an efficient method of conveying complex information and specifications on the performance requirements for materials, products, systems, application, and installation. The manner and purpose for a standard’s use and, in turn, code compliance, must be definitive in all references to the standard. If the standard is intended to be a requirement for judging code compliance, the code must state its intent for use. The standard should adequately address a defined need and at the same time specify the minimum performance requirements, technical characteristics and methods of testing, and required test results.

The referenced standards tables are organized in a manner that makes it easy to find specific standards in alphabetical order, and by acronym of the publishing agency of the standard. The tables list the title of the standard, the edition, and any addenda. Contact information for each publishing agency is provided at the end of the chapter.

Appendix A Residential Plans Examiner Review Form for HVAC System Design. A residential plans examiner review form is located in this appendix as an example to assist users in identifying whether the HVAC system has followed the approved procedures for system design (loads, equipment, and ducts).

Appendix B Procedures to be Followed to Place Gas Equipment in Operation. Appendix B provides requirements for the procedures that apply after an appliance is installed in place, piped, and connected to its venting system. The requirements include adjusting the burner input, air adjustments, verifying operation of safety shutoffs, automatic ignition, and protective devices, checking draft for vent-connected appliances, and operating instructions.

Appendix C Installation and Testing of Oil (Liquid) Fuel-Fired Equipment. Appendix C governs the installation, testing, or repair of oil or liquid fuel-burning equipment used in buildings or structures and equipment.

Appendix D Fuel Supply: Manufactured/Mobile Home Parks and Recreational Vehicle Parks. The provisions of this appendix apply to the fuel gas piping systems of mobile home and recreational vehicle parks. These provisions also apply to the use, maintenance, and installation for supplying fuel gas for accessory buildings or structures, and building components.

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FORMAT OF THE UNIFORM MECHANICAL CODE

Appendix E Sustainable Practices. This appendix provides a comprehensive set of technically sound provisions that encourage sustainable practices and works toward improving the design and construction of mechanical systems that result in a positive long-term environmental impact. Environmental sustainability is important because it involves natural resources that human beings need for economic or manufactured capital. Their sustainability is defined by their reliance on infinitely available resources that are naturally occurring, constant, and free to access.

Appendix F Sizing of Venting Systems and Outdoor Combustion and Ventilation Opening Design. Appendix F provides added information on the sizing of gas vents. This appendix is useful to the end user for the proper sizing of venting systems. A series of examples are given that show how to use the tables and other requirements of Chapter 8. In addition, Appendix F shows an example of how to determine the required combination of indoor and outdoor combustion air opening sizes for appliances under Chapter 7. The combustion air example also provides a table that contains the required volume of space per the appliance Btu/h input based on the standard method.

Appendix G Example Calculation of Outdoor Air Rate. Appendix G gives an example of how to calculate the required outdoor air rate under Chapter 4.

Appendix H Professional Qualifications. Appendix H provides a baseline of knowledge for installers, inspectors, or employers working with and around systems covered within the scope of this code to maintain health and safety.

Appendix I Indoor Horticultural Facilities. Appendix I addresses indoor spaces using environmental controls for horticultural cultivation and processing of plants for human ingestion, inhalation, and topical application. The appendix includes recommendations pertaining to fire protection and suppression systems, carbon dioxide detection systems, flammable solvents, ventilation and exhaust systems, particulate and odor control, and fumigation.

pendix I addresses indoor spaces using environmental controls for horticultural cultivation and processing of plants for human ingestion, inhalation, and topical application. The appendix includes recommendations pertaining to fire protection and suppression systems, carbon dioxide detection systems, flammable solvents, ventilation and exhaust systems, particulate and odor control, and fumigation.

Appendix J Clean Air Delivery. Appendix J provides criteria for an increased level of protection for occupant health by delivering and monitoring clean air in occupied areas of certain buildings. This appendix addresses Demand Control Ventilation (DCV) for occupancy groups A, B, E, and I and recommends that each occupiable zone have CO 2 sensors which communicate with building mechanical systems to adjust airflow rates and maintain acceptable CO 2 levels. Additionally, this appendix contains provisions for mechanical system controls pertaining to sensor calibration, intervals for collected data, and automatic remediation actions to increase the amount of outdoor air provided to each occupiable zone. The CO 2 sensors addressed in this appendix are intended to give notifications that can assist with awareness of unhealthy levels and give insight to building occupants as to when mitigation action is necessary.

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SAMPLE LEGISLATION FOR ADOPTION OF THE UNIFORM MECHANICAL CODE

The Uniform Codes are designed to be adopted by jurisdictions through an ordinance. Jurisdictions wishing to adopt the 2024 Uniform Mechanical Code as an enforceable regulation governing mechanical systems by reference should ensure the legal basis under which adoption and implementation are included in the ordinance.

The following sample ordinance is a guide for drafting an ordinance for adoption that addresses key components regulations and resolutions.

ORDINANCE NO.

An ordinance of the [JURISDICTION] adopting the 2024 edition of the Uniform Mechanical Code, regulating and controlling the design, construction, quality of materials, erection, installation, alteration, repair, location, relocation, replacement, addition to, use or maintenance of mechanical systems in the [JURISDICTION]; providing for the issuance of permits and collection of fees therefor; repealing Ordinance No. of the

[JURISDICTION] and all other ordinances and parts of the ordinances in conflict therewith.

The [GOVERNING BODY] of the [JURISDICTION] does ordain as follows:

Section 1 Codes Adopted by Reference. That certain documents, three (3) copies of which are on file in the office of the [JURISDICTION'S KEEPER OF RECORDS] and the [JURISDICTION], being marked and designated as the 2024 Uniform Mechanical Code, including Appendix Chapters [FILL IN THE APPENDIX CHAPTERS BEING ADOPTED], as published by the International Association of Plumbing and Mechanical Officials, be and is hereby adopted as the Code of the [JURISDICTION], in the State of [STATE NAME] regulating and controlling the design, construction, quality of materials, erection, installation, alteration, repair, location, relocation, replacement, addition to, use or maintenance of mechanical systems as herein provided; providing for the issuance of permits and collection of fees therefor; and each and all of the regulations, provisions, penalties, conditions and terms of such 2024 Uniform Mechanical Code on file in the office of the

[JURISDICTION] are hereby referred to, adopted, and made a part hereof, as if fully set out in this ordinance.

Section 2 Modifications. The following sections are hereby revised: Section 101.1. Insert: [NAME OF JURISDICTION] Section 104.5. Insert: [APPROPRIATE FEE SCHEDULE]

Section 3 Conflicting Ordinances Repealed. That Ordinance No. of [JURISDICTION] entitled

[TITLE OF THE ORDINANCE OR ORDINANCES IN EFFECT AT THE PRESENT TIME SO THAT THEY WILL BE REPEALED BY MENTION] and all other ordinances or parts of ordinances in conflict herewith are hereby repealed.

Section 4 Preemption. [JURISDICTION] hereby fully occupies and preempts the entire field of regulation of design, construction, quality of materials, erection, installation, alteration, repair, location, relocation, replacement, addition to, use or maintenance of mechanical systems; and provision for the issuance of permits and collection of fees therefor; within the boundaries of [JURISDICTION]. [AS APPROPRIATE] Cities, towns, and counties or other municipalities may enact only those laws and ordinances relating to this field as specifically authorized by state law and consistent with this ordinance. Local laws and ordinances that are inconsistent with, more restrictive than, or exceed the requirements of [ORDINANCE NO.] shall not be enacted and are hereby expressly preempted and repealed, regardless of the nature of the code, charter, or home rule status of such city, town, county, or municipality.

Section 5 Severability. That if any section, subsection, sentence, clause or phrase of this ordinance is, for any reason, held to be unconstitutional, such decision shall not affect the validity of the remaining portions of this ordinance. The [GOVERNING BODY] hereby declares that it would have passed this ordinance, and each section, subsection, clause or phrase thereof, irrespective of the fact that any one or more sections, subsections, sentences, clauses and phrases be declared unconstitutional.

, for any reason, held to be unconstitutional, such decision shall not affect the validity of the remaining portions of this ordinance. The [GOVERNING BODY] hereby declares that it would have passed this ordinance, and each section, subsection, clause or phrase thereof, irrespective of the fact that any one or more sections, subsections, sentences, clauses and phrases be declared unconstitutional.

Section 6 Legal Notice. That the [JURISDICTION'S KEEPER OF RECORDS] is hereby ordered and directed to cause this ordinance to be published. (An additional provision may be required to direct the number of times the ordinance is to be published and to specify that it is to be in a newspaper in general circulation. Posting may also be required.)

Section 7 Violations and Penalties. [INCORPORATE PENALTIES FOR VIOLATIONS]

Section 8 Effective Date. That this ordinance and the rules, regulations, provisions, requirements, orders and matters established and adopted hereby shall take effect and be in full force and effect [TIME PERIOD] from and after the date of its final passage and adoption.

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COMMITTEE ON UNIFORM MECHANICAL CODE

These lists represent the membership at the time the Committee was balloted on the final text of this edition. Since that time, changes in the membership may have occurred.

IAPMO Standards Council Bill Erickson, Chairperson, CJ Erickson Plumbing Company [I/M]

JT Baca, State of New Mexico [E]

Laura Ceja, United Association [L]

Rick Coffman, City of Cedar Falls, Retired [C]

Marty Cooper, Vice Chairperson, City of Foster City [E]

Jim Imprescia, City of Leominster [E]

Doug Marian, District Council 16 [L]

Jim Stack, Stack Plumbing, Inc. [I/M]

Don Summers, Plumber’s & Pipefitters Training Center [L]

Nonvoting

Gabriella M. Davis, Secretary, IAPMO Hugo Aguilar, Recording Secretary, IAPMO

IAPMO Uniform Mechanical Code Technical Committee Harvey Kreitenberg, Chairperson, Harvey Kreitenberg & Associates [SE]

Bob Adler, 4 Leaf, Inc. [E] Sarah Aguilar, Ciari Plumbing & Heating [I/M] Rawand Aryan, City of Los Angeles Department of Building & Safety [E] Julius Ballanco, JB Engineering & Code Consulting [SE] DJ Berger, National ITC Corporation [U] Michael Cudahy, Plastic Pipe & Fittings Association (PPFA) [M] David Dias, Sheet Metal Workers Local 104 [L] Jay Egg, EggGeothermal Consulting [C] Pennie Feehan, Copper Development Association (CDA) [M] Brian Fenty, Self [E] Aaron Gunzner, Air Movement and Control Association International (AMCA) [R/S/T] John Hamilton, National Energy Management Institute Committee (NEMIC) [R/S/T] John Heine, Heine Plumbing & Heating [I/M] Ralph Koerber, Air Duct Council [M] Lance MacNevin, Plastics Pipe Institute (PPI) [SE]

g [C] Pennie Feehan, Copper Development Association (CDA) [M] Brian Fenty, Self [E] Aaron Gunzner, Air Movement and Control Association International (AMCA) [R/S/T] John Hamilton, National Energy Management Institute Committee (NEMIC) [R/S/T] John Heine, Heine Plumbing & Heating [I/M] Ralph Koerber, Air Duct Council [M] Lance MacNevin, Plastics Pipe Institute (PPI) [SE]

Dave Mann, CA State Pipe Trades Council [L] John Nielsen, State of Idaho - Division of Building Safety [E] Phil Ribbs, PHR Consultants [SE] Robert Sewell, Lescure Company [U] Donald Cary Smith, Sound Geothermal Corporation [SE] Don Taylor, Dittmann Plumbing [U] Mark Terzigni, Sheet Metal & Air Conditioning Contractors’ National Association (SMACNA) [R/S/T] April Trafton, Donald F. Dickerson Associates [SE] Phil Trafton, American Society of Heating, Refrigerating & Air-Conditioning Engineers (ASHRAE) [R/S/T] Chris Van Rite, Air Distribution Institute (ADI) [M] Robert Vilches, United Association [L] Randy Young, Northern CA Valley Sheet Metal Industry JATC [L] Chuck White, Plumbing-Heating-Cooling Contractors National Association (PHCC-NA) [I/M] Bob Wiseman, Air Conditioning Contractors of America (ACCA) [I/M]

Mike Afonso, UA Local 342 [L] David Bixby, Air Conditioning Contractors of America (ACCA) [I/M] Richard Church, Plastic Pipe & Fittings Association (PPFA) [M] Andrew Davie, Mesa Energy Systems Inc. [U] Duane Davis, Sheet Metal & Air Conditioning Contractors’ National Association (SMACNA) [R/S/T] Kristy Egg, EggGeothermal Consulting [C] Michael Galfano, United Association [L] Mat Hattich, UA Local 342 [L]

Alternates

Shawn Hargis, City of Los Angeles Department of Building & Safety [E] Robert Kuks, Northern CA Joint Apprenticeship Committee [L] Tim Orris, Air Movement and Control Association International (AMCA) [R/S/T] Luis Reyes, National ITC Corporation [U] Chris Ruch, National Energy Management Institute Committee (NEMIC) [R/S/T] Jason Shelton, Air Duct Council [M] Bob Whittington, Air Distribution Institute (ADI) [M]

Nonvoting

Alexander Ing, National Fire Protection Association (NFPA) [R/S/T] Matthew Barker, National Fire Protection Association (NFPA) [R/S/T] Taylor Duran, IAPMO Staff Liaison David Gans, Ex-Officio IAPMO [E]

COMMITTEE MEMBERSHIP CLASSIFICATION ABBREVIATIONS

These classifications apply to Technical Committee members and represent their principal interest in the activity of a committee. M Manufacturer : A representative of a maker or marketer of a product, assembly or system, or portion thereof, that is affected by the standard. U User : A representative of an entity that is subject to the provisions of the standard or that voluntarily uses the standard. I/M Installer/Maintainer : A representative of an entity that is in the business of installing or maintaining a product, assembly or system affected by

the standard.

L Labor : A labor representative or employee concerned with safety in the workplace. R/S/T Research/Standards/Testing Laboratory : A representative of an independent research organization; an organization that develops codes, standards or other similar documents; or an independent testing laboratory. E Enforcing Authority : A representative or an agency or an organization that promulgates and/or enforces standards. C Consumer : A person who is, or represents, the ultimate purchaser of a product, system, or service affected by the standard, but who is not

included in the User classification.

SE Special Expert : A person not representing any of the previous classifications, but who has special expertise in the scope of the standard or portion

thereof.

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SECTION RELOCATION

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SECTION RELOCATION

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RELATED PUBLICATIONS AND SERVICES

The Documents Listed are Not by this Reference Adopted by The State of California.

IAPMO provides a variety of other products which are useful for inspectors, building officials, architects, engineers,

manufacturers, contractors, plumbers, and apprentices.

IAPMO Headquarters Directory

4755 East Philadelphia Street, Ontario, California 91761-2816

Publication Order Desk Phone: 800-85-IAPMO

Publication Toll Free Fax: 877-85-CODES

E-mail: iapmo@iapmo.org

Website: www.iapmo.org

Free Code Question: 800-201-0335

Uniform Mechanical Code – 2024 Edition:

The Uniform Mechanical Code contains complete requirements for the installation and maintenance of heating, ventilating, cooking and refrigeration systems.

Uniform Mechanical Code Illustrated Training Manual:

Contains technical diagrams and illustrations that demonstrate the intent and use of the UMC. A great reference for everyone involved in Mechanical HVACR design and installation.

Uniform Mechanical Code Study Guide:

The Study Guide is a complete self-study course for learning the UMC. A big help in getting ready for a certification exam! This book is the perfect complement to the UMC Illustrated Training Manual.

Guide to Important Code Questions to the Uniform Mechanical Code:

An excellent reference for learning and understanding mechanical code changes and identifies code changes between editions. It is a useful tool for preparing code change proposals.

Uniform Plumbing Code – 2024 Edition:

The Uniform Plumbing Code is the most widely adopted plumbing code in the world. The 2024 edition contains complete “turnkey” requirements for the installation and maintenance of plumbing systems, all in one easy to use book.

Uniform Plumbing Code Illustrated Training Manual:

The UPC Illustrated Training Manual is an excellent reference for anyone involved in the plumbing industry. It contains an extensive definitions section and several hundred comprehensive technical diagrams and illustrations. It serves as a textbook, and it also is useful as a valuable tool for explaining the intent and use of the Code.

Uniform Plumbing Code Study Guide:

This book is the perfect complement to the UPC Illustrated Training Manual. Alone, it constitutes a complete self-study course for learning the UPC. It has hundreds of questions, general practice exams, and plumbing math, pipe sizing exercises and fitting identification. A big help in getting you ready for a certification exam!

Guide to Important Code Questions to the Uniform Plumbing Code:

An excellent reference for learning and understanding plumbing code changes and identifies code changes between editions. It is a useful tool for preparing code change proposals.

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

RELATED PUBLICATIONS AND SERVICES

The Documents Listed are Not by this Reference Adopted by The State of California.

Uniform Swimming Pool, Spa, and Hot Tub Code – 2024 Edition: The Uniform Swimming Pool, Spa and Hot Tub Code contains complete and current requirements for the erection, installation, alteration, repair, relocation, replacement, addition to and use or maintenance of these systems.

Uniform Solar, Hydronics and Geothermal Code – 2024 Edition: The Uniform Solar, Hydronics and Geothermal Code contains complete requirements for the erection, installation, alteration, addition, repair, relocation, replacement, addition to, use or maintenance of these systems.

Drain Waste and Vent Calculator:

A slide-rule style calculator provides quick and simple access to the fixture unit and sizing tables of Chapter 7 of the UPC.

Water Sizing Calculator: Sizing water systems becomes a much simpler task with the use of this handy slide-rule style calculator.

Natural Gas Pipe Sizing Calculator: This Natural Gas Pipe Sizing Calculator is presented in an easy to use and read slide-rule format. Designed for systems with a supply pressure of six to eight inches of water column, all pipe capacities are given in cubic feet per hour.

Trailer Standards:

IAPMO has developed a number of standards for specialty products used in manufactured homes and recreational vehicles. These standards are available individually, or they may be purchased as a set.

Education and Training Seminars: IAPMO specializes in conducting training and education, including fulfilling continuing education requirements, on the UPC and UMC as well as all of the most commonly utilized codes in the Construction Trades. Special seminars on industry or code subjects are expeditiously created and delivered upon request. Please call to obtain the seminar schedule or to arrange for a custom special seminar.

Backflow Prevention Institute – IAPMO:

The IAPMO Backflow Prevention Institute provides professional education and training for the control of hazards to our water supply and is dedicated to water-system safety worldwide. The Institute provides training in backflow prevention and cross-connection control. This program includes backflow preventers, testers, repairers, cross-connection control surveyors, program administrators and fire-sprinkler backflow preventer testers. Each of these courses provides compliance certification to American Society of Sanitary Engineering (ASSE) Series 5000 Professional Qualification Standards.

Backflow Prevention Reference Manual:

This unique 300-page manual contains full-color illustrations and sections relating to real-world installations, backflow prevention, testing cross-connection control, repair and inspections. The manual is an excellent textbook and a reference the inspectors in every jurisdiction should have access too. It is also an important resource for system designers, urban planners and utility companies – professionals on both sides of the water meter.

ANSI Z124 Standards:

These standards are written to specifically address a variety of plastic plumbing fixtures and components. They are available individually, or may be grouped for quantity discounts.

IAPMO Installation Standards:

IAPMO standards committees have formulated installation standards for a wide variety of commonly used plumbing materials and systems. The IAPMO installation standards are included after the text of the Uniform Plumbing Code, or can be purchased separately.

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RELATED PUBLICATIONS AND SERVICES

The Documents Listed are Not by this Reference Adopted by The State of California.

Material and Property Standards: IAPMO does not generally develop material and property standards, but when a need exists the Association will take a leadership role by filling the void. They are available, are subject to amendments and are withdrawn when recognized consensus standards are formulated.

OFFICIAL Magazine: IAPMO’s quarterly publication features informative articles related to Plumbing and Mechanical HVACR installations, award winning general interest features, technical columns and industry updates. Subscriptions are available and all IAPMO members receive a free copy of every issue!

Membership in IAPMO: IAPMO membership is open to all interested persons. Membership categories include Student, Individual, Senior, Organizational and Governmental. Member benefits include discounted prices on IAPMO publications, a subscription to Official magazine, and numerous educational and training opportunities.

HOW TO CONTACT IAPMO

Mailing Address: 4755 East Philadelphia Street, Ontario, California 91761-2816

Main Number: 909-472-4100 • Publication Orders: 800-85-IAPMO • Publication Fax: 877-85-CODES

Website: www.iapmo.org • Office Hours: Monday – Friday, 8am – 5pm Pacific Time

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TABLE OF CONTENTS

CHAPTER 1 DIVISION I

CALIFORNIA ADMINISTRATION . . . . 1

1.1.0 General . . . . . . . . . . . . . . . . . . . . . . .3

1.1.1 Title . . . . . . . . . . . . . . . . . . . . . . . . . .3

1.1.2 Purpose . . . . . . . . . . . . . . . . . . . . . .3

1.1.3 Scope . . . . . . . . . . . . . . . . . . . . . . . .3

1.1.4 Appendices . . . . . . . . . . . . . . . . . . .4

1.1.5 Referenced Codes . . . . . . . . . . . . . .4

1.1.6 NonBuilding Standards, Orders,

and Regulations . . . . . . . . . . . . . . . .4

1.1.7 Order of Precedence and Use . . . . .4

1.1.8 City, County, or City and County

Amendments, Additions or

Deletions . . . . . . . . . . . . . . . . . . . . . .5

1.1.9 Effective Date of This Code . . . . . . .5

1.1.10 Availability of Codes . . . . . . . . . . . . .5

1.1.11 Format . . . . . . . . . . . . . . . . . . . . . . .5

1.1.12 Validity . . . . . . . . . . . . . . . . . . . . . . .5

1.2.0 Building Standards Commission . . .5

1.2.1 BSC . . . . . . . . . . . . . . . . . . . . . . . . .5

1.2.2 BSC-CG . . . . . . . . . . . . . . . . . . . . . .6

1.2.3 Alternative Materials, Design,

and Methods of Construction

and Equipment . . . . . . . . . . . . . . . . .6

1.3.0 Reserved for Board of State and

Community Corrections . . . . . . . . . .7

1.4.0 Department of Consumer Affairs . . .7

1.4.2 Adopting Agency Identification . . . .7

1.5.0 Reserved for California Energy

Commission . . . . . . . . . . . . . . . . . . .7

1.6.0 Reserved for Department of

Food and Agriculture . . . . . . . . . . . .7

1.7.0 California Department of

Public Health . . . . . . . . . . . . . . . . . .7

1.7.2 Adopting Agency Identification . . . .7

1.8.0 Department of Housing and

Community Development [HCD] . . .7

1.8.1 Purpose . . . . . . . . . . . . . . . . . . . . . .7

1.8.2 Authority and Abbreviations . . . . . . .7

1.8.3 Local Enforcing Agency . . . . . . . . . .8

1.8.4 Permits, Fees, Applications,

and Inspections . . . . . . . . . . . . . . . .9

1.8.5 Right of Entry for Enforcement . . . . .9

1.8.6 Local Modification by Ordinance

or Regulation . . . . . . . . . . . . . . . . .10

1.8.7 Alternate Materials, Designs, Tests,

and Methods of Construction . . . . .10

1.8.8 Appeals Board . . . . . . . . . . . . . . . .11

1.8.9 Unsafe Buildings or Structures . . .11

1.8.10 Other Building Regulations . . . . . .12

1.9.0 Division of the State Architect . . . .12

1.9.1 Reserved for the Division of the State

Architect – Access Compliance . . .12

1.9.2 Division of the State Architect –

Structural Safety . . . . . . . . . . . . . . .12

1.10.0 Department of Health Care Access and Information/Office

of Statewide Hospital Planning and Development . . . . . . . . . . . . .13

1.10.1 OSHPD 1 and OSHPD 1R . . . . . . .13

1.10.2 OSHPD 2 . . . . . . . . . . . . . . . . . . . .13

1.10.3 OSHPD 3 . . . . . . . . . . . . . . . . . . . .13

1.10.4 OSHPD 4 . . . . . . . . . . . . . . . . . . . .13

1.10.5 OSHPD 5 . . . . . . . . . . . . . . . . . . . .14

1.10.6 OSHPD 6 . . . . . . . . . . . . . . . . . . . .14

1.11.0 Office of the State Fire Marshal . . .14

1.11.1 SFM – Office of the State

Fire Marshal . . . . . . . . . . . . . . . . . .14

1.11.2 Duties and Powers of the

Enforcing Agency . . . . . . . . . . . . . .16

1.11.3 Construction Documents . . . . . . . .17

1.11.4 Fees . . . . . . . . . . . . . . . . . . . . . . . .18

1.11.5 Inspections . . . . . . . . . . . . . . . . . . .19

1.11.6 Certificate of Occupancy . . . . . . . .19

1.11.7 Temporary Structures and Uses . .19

1.11.8 Service Utilities . . . . . . . . . . . . . . . .19

1.11.9 Stop Work Order . . . . . . . . . . . . . .19

1.11.10 Unsafe Buildings, Structures,

and Equipment . . . . . . . . . . . . . . . .19

1.11.11 Adopting Agency Identification . . .19

1.12.0 Reserved for the State Librarian . .19

1.13.0 Reserved for the Department

of Water Resources . . . . . . . . . . . .19

1.14.0 Reserved for the State Lands

Commission . . . . . . . . . . . . . . . . . .19

CHAPTER 1 DIVISION II

SCOPE AND ADMINISTRATION. . .21

101.0 General. . . . . . . . . . . . . . . . . . . . . . 21

101.1 Title. . . . . . . . . . . . . . . . . . . . . . . . . 21

101.2 Scope . . . . . . . . . . . . . . . . . . . . . . . 21

101.3 Purpose . . . . . . . . . . . . . . . . . . . . . 21

101.4 Unconstitutional . . . . . . . . . . . . . . . 21

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TABLE OF CONTENTS

101.5 Validity . . . . . . . . . . . . . . . . . . . . . . 21

102.0 Applicability. . . . . . . . . . . . . . . . . . . 21

102.1 Conflicts Between Codes . . . . . . . . 21

102.2 Existing Installations . . . . . . . . . . . . 21

102.3 Maintenance . . . . . . . . . . . . . . . . . . 21

102.4 Additions, Alterations, Renovations, or Repairs . . . . . . . . . 21

102.5 Health and Safety . . . . . . . . . . . . . . 21

102.6 Changes in Building Occupancy. . . 21

102.7 Moved Structures . . . . . . . . . . . . . . 21

102.8 Appendices. . . . . . . . . . . . . . . . . . . 21

103.0 Duties and Powers of the

Authority Having Jurisdiction . . . . . 22

103.1 General. . . . . . . . . . . . . . . . . . . . . . 22

103.2 Liability . . . . . . . . . . . . . . . . . . . . . . 22

103.3 Applications and Permits . . . . . . . . 22

103.4 Right of Entry . . . . . . . . . . . . . . . . . 22

104.0 Permits . . . . . . . . . . . . . . . . . . . . . . 22

104.1 Permits Required . . . . . . . . . . . . . . 22

104.2 Exempt Work . . . . . . . . . . . . . . . . . 22

104.3 Application for Permit . . . . . . . . . . . 22

104.4 Permit Issuance . . . . . . . . . . . . . . . 23

104.5 Fees . . . . . . . . . . . . . . . . . . . . . . . . 24

105.0 Inspections and Testing . . . . . . . . . 24

105.1 General. . . . . . . . . . . . . . . . . . . . . . 24

105.2 Required Inspections . . . . . . . . . . . 24

105.3 Testing of Systems . . . . . . . . . . . . . 25

105.4 Connection to Service Utilities . . . . 25

106.0 Violations and Penalties . . . . . . . . . 25

106.1 General. . . . . . . . . . . . . . . . . . . . . . 25

106.2 Notices of Correction or Violation . . 25

106.3 Penalties. . . . . . . . . . . . . . . . . . . . . 26

106.4 Stop Orders . . . . . . . . . . . . . . . . . . 26

106.5 Authority to Disconnect Utilities in Emergencies. . . . . . . . . . . . . . . . 26

106.6 Authority to Condemn. . . . . . . . . . . 26

107.0 Board of Appeals . . . . . . . . . . . . . . 26

107.1 General. . . . . . . . . . . . . . . . . . . . . . 26

107.2 Limitations of Authority . . . . . . . . . . 26

Table 104.5 Mechanical Permit Fees . . . . . . . . . 27

CHAPTER 2 DEFINITIONS. . . . . . . . . . . . . . . . . 29

201.0 General. . . . . . . . . . . . . . . . . . . . . . 31

201.1 Applicability. . . . . . . . . . . . . . . . . . . 31

202.0 Definition of Terms . . . . . . . . . . . . . 31

202.1 General. . . . . . . . . . . . . . . . . . . . . . 31

CHAPTER 3 GENERAL REGULATIONS. . . . . . 49

301.0 General. . . . . . . . . . . . . . . . . . . . . . 51

301.1 Applicability. . . . . . . . . . . . . . . . . . . 51

301.2 Approval . . . . . . . . . . . . . . . . . . . . . 51

301.3 Design of Equipment . . . . . . . . . . . 51

301.4 Electrical Connections . . . . . . . . . . 51

301.5 Oil-Burning Appliances . . . . . . . . . . 51

301.6 Personnel Protection . . . . . . . . . . . 51

302.0 Materials – Standards and

Alternates . . . . . . . . . . . . . . . . . . . . 51

302.1 Minimum Standards . . . . . . . . . . . . 51

302.2 Alternate Materials and Methods

of Construction Equivalency . . . . . . 51

302.3 Alternative Engineered Design. . . . 52

303.0 Installation . . . . . . . . . . . . . . . . . . . 52

303.1 Listed Appliances . . . . . . . . . . . . . . 52

303.2 Closet or Alcove Installations . . . . . 52

303.3 Unlisted Appliances . . . . . . . . . . . . 52

303.4 Anchorage of Appliances . . . . . . . . 52

303.5 Restraining Device . . . . . . . . . . . . . 53

303.6 Identification of Equipment . . . . . . . 53

303.7 Liquefied Petroleum Gas (LP-Gas) Facilities . . . . . . . . . . . . . . 53

303.8 Appliances on Roofs. . . . . . . . . . . . 53

303.9 Avoiding Strain on Gas Piping . . . . 53

303.10 Clearance to Combustible

Materials . . . . . . . . . . . . . . . . . . . . . 53

303.11 Installation in Commercial

Garages . . . . . . . . . . . . . . . . . . . . . 54

303.12 Installation in Aircraft Hangars . . . . 54

304.0 Accessibility for Service . . . . . . . . . 54

304.1 General. . . . . . . . . . . . . . . . . . . . . . 54

304.2 Sloped Roof . . . . . . . . . . . . . . . . . . 54

304.3 Access to Appliances on Roofs . . . 54

304.4 Appliances in Attics and Under-Floor Spaces . . . . . . . . . . . . 54

305.0 Location . . . . . . . . . . . . . . . . . . . . . 55

305.1 Installation in Residential Garages . . 55

305.2 Pit Location. . . . . . . . . . . . . . . . . . . 55

305.3 Flood Hazard Areas . . . . . . . . . . . . 55

305.4 Elevator Shaft . . . . . . . . . . . . . . . . . 55

305.5 Drainage Pan . . . . . . . . . . . . . . . . . 55

305.6 Outdoor Locations . . . . . . . . . . . . . 55

306.0 Automatic Control Devices . . . . . . . 55

306.1 General. . . . . . . . . . . . . . . . . . . . . . 55

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

TABLE OF CONTENTS

307.0 Labeling . . . . . . . . . . . . . . . . . . . . . 56

307.1 Fuel-Burning Appliances . . . . . . . . 56

307.2 Electric Heating Appliances . . . . . . 56

307.3 Heat Pump and Electric Cooling Appliances . . . . . . . . . . . . . . . . . . . 56

307.4 Absorption Units . . . . . . . . . . . . . . . 56

308.0 Improper Location. . . . . . . . . . . . . . 57

308.1 General. . . . . . . . . . . . . . . . . . . . . . 57

309.0 Workmanship . . . . . . . . . . . . . . . . . 57

309.1 Engineering Practices. . . . . . . . . . . 57

309.2 Concealing Imperfections . . . . . . . . 57

309.3 Installation Practices. . . . . . . . . . . . 57

310.0 Condensate Wastes and Control . . 57

310.1 Condensate Disposal . . . . . . . . . . . 57

310.2 Condensate Control . . . . . . . . . . . . 57

310.3 Condensate Waste Pipe Material and Sizing. . . . . . . . . . . . . . . . . . . . 57

Table 310.3 Minimum Condensate Pipe Size. . . 57

310.4 Appliance Condensate Drains . . . . 58

310.5 Point of Discharge . . . . . . . . . . . . . 58

310.6 Condensate Waste from

Air-Conditioning Coils . . . . . . . . . . . 58

310.7 Female Plastic Connections . . . . . . 58

311.0 Heating or Cooling Air System . . . . 58

311.1 Source . . . . . . . . . . . . . . . . . . . . . . 58

311.2 Air Filters . . . . . . . . . . . . . . . . . . . . 58

311.3 Prohibited Sources . . . . . . . . . . . . . 58

311.4 Return-Air Limitations . . . . . . . . . . . 58

Requirements for Residential

Air Filtration . . . . . . . . . . . . . . . . . . 59

312.0 Plumbing Connections . . . . . . . . . . 59

312.1 General. . . . . . . . . . . . . . . . . . . . . . 59

313.0 Hangers, Supports, and Anchors . . 59

313.1 General. . . . . . . . . . . . . . . . . . . . . . 59

313.2 Material. . . . . . . . . . . . . . . . . . . . . . 59

313.3 Suspended Piping . . . . . . . . . . . . . 59

313.4 Alignment . . . . . . . . . . . . . . . . . . . . 59

313.5 Underground Installation . . . . . . . . 59

313.6 Hanger Rod Sizes . . . . . . . . . . . . . 59

Table 313.6 Hanger Rod Sizes . . . . . . . . . . . . . 59

313.7 Gas Piping . . . . . . . . . . . . . . . . . . . 59

314.0 Balancing . . . . . . . . . . . . . . . . . . . . 59

314.1 General. . . . . . . . . . . . . . . . . . . . . . 59

315.0 Louvers in Hurricane Prone

Regions . . . . . . . . . . . . . . . . . . . . . 59

315.1 General. . . . . . . . . . . . . . . . . . . . . . 59

316.0 Protection of Piping, Tubing, Materials, and Structures . . . . . . . . 59

316.1 General. . . . . . . . . . . . . . . . . . . . . . 59

316.2 Installation . . . . . . . . . . . . . . . . . . . 59

316.3 Corrosion, Erosion, and Mechanical Damage. . . . . . . . . . . . 59

316.4 Protectively Coated Pipe . . . . . . . . 59

316.5 Fire-Resistant Construction . . . . . . 59

316.6 Steel Nail Plates . . . . . . . . . . . . . . . 60

316.7 Sleeves. . . . . . . . . . . . . . . . . . . . . . 60

316.8 Firewalls . . . . . . . . . . . . . . . . . . . . . 60

316.9 Structural Members . . . . . . . . . . . . 60

316.10 Rodentproofing . . . . . . . . . . . . . . . . 60

316.11 Metal Collars. . . . . . . . . . . . . . . . . . 60

317.0 Trenching, Excavation, and

Backfill . . . . . . . . . . . . . . . . . . . . . . 60

317.1 Trenches. . . . . . . . . . . . . . . . . . . . . 60

317.2 Tunneling and Driving. . . . . . . . . . . 60

317.3 Open Trenches. . . . . . . . . . . . . . . . 60

317.4 Excavations . . . . . . . . . . . . . . . . . . 60

Optional Services Provided in Correctional Treatment Centers . . . 60

Nursing, Intermediate Care Facilities and Basic Services

Provided in Correctional

Treatment Centers . . . . . . . . . . . . . 61

Heating Systems . . . . . . . . . . . . . . 61

Optional Services Provided in Correctional Treatment Centers . . . 61

Nursing, Intermediate Care Facilities and Basic Services

Provided in Correctional

Treatment Centers . . . . . . . . . . . . . 61

Facilities and Licensed Clinics. . . . 61

Equipment Centers. . . . . . . . . . . . . 61

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

TABLE OF CONTENTS

Schedules . . . . . . . . . . . . . . . . . . . 62

Generators . . . . . . . . . . . . . . . . . . . 62

Safe Temperatures. . . . . . . . . . . . . 62

Table 303.10.1 Reduction of Clearances with

Specified Forms of Protection . . . . 63

Table 313.3 Hangers and Supports . . . . . . . . . . 65

CHAPTER 4 VENTILATION AIR . . . . . . . . . . . . 67

401.0 General. . . . . . . . . . . . . . . . . . . . . . 69

401.1 Applicability. . . . . . . . . . . . . . . . . . . 69

401.2 Indoor Swimming Pools . . . . . . . . . 69

402.0 Ventilation Air . . . . . . . . . . . . . . . . . 69

402.1 Occupiable Spaces. . . . . . . . . . . . . 69

402.2 Natural Ventilation Procedure. . . . . 70

Table Minimum Openable Areas:

402.2.1.6(A)(1) Single Openings . . . . . . . . . . . . . . . 71

Table Minimum Openable Areas:

402.2.1.6(A)(2) Two Vertically

Spaced Openings . . . . . . . . . . . . . . 71

402.3 Mechanical Ventilation . . . . . . . . . . 71

402.4 Outdoor Air Intakes. . . . . . . . . . . . . 71

Table 402.4.1 Air Intake Minimum

Separation Distance . . . . . . . . . . . . 72

403.0 Ventilation Rates . . . . . . . . . . . . . . 72

403.1 General. . . . . . . . . . . . . . . . . . . . . . 72

403.2 Zone Calculations. . . . . . . . . . . . . . 73

403.3 Single-Zone Systems . . . . . . . . . . . 73

403.4 One Hundred Percent Outdoor

Air Systems . . . . . . . . . . . . . . . . . . 73

403.5 Multiple-Zone Recirculating Systems . . . . . . . . . . . . . . . . . . . . . 73

403.6 Design for Varying Operating Conditions. . . . . . . . . . . . . . . . . . . . 74

403.7 Exhaust Ventilation. . . . . . . . . . . . . 74

403.8 Dynamic Reset . . . . . . . . . . . . . . . . 75

403.9 Air Classification and

Recirculation. . . . . . . . . . . . . . . . . . 75

Table 403.9 Airstreams or Sources

Description Air Class . . . . . . . . . . . 75

403.10 Air Balance . . . . . . . . . . . . . . . . . . . 75

404.0 Alternative Procedure for

Multiple-Zone Systems Ventilation Efficiency . . . . . . . . . . . 76

404.1 System Ventilation Efficiency . . . . . 76

404.2 Average Outdoor Air Fraction. . . . . 76

404.3 Zone Ventilation Efficiency . . . . . . . 76

405.0 Ventilation for Residential

Occupancies. . . . . . . . . . . . . . . . . . 77

405.1 General. . . . . . . . . . . . . . . . . . . . . . 77

405.2 Ventilation Air Rate. . . . . . . . . . . . . 77

405.3 Bathroom Exhaust . . . . . . . . . . . . . 77

405.4 Kitchen Exhaust . . . . . . . . . . . . . . . 77

405.5 Ventilation Openings . . . . . . . . . . . 77

for Health Care Facilities . . . . . . . . 78

Exhaust Outlets . . . . . . . . . . . . . . . 78

Facilities, Intermediate Care Facilities, and Correctional

Treatment Centers . . . . . . . . . . . . . 80

Room Units. . . . . . . . . . . . . . . . . . . 80

and Hoods . . . . . . . . . . . . . . . . . . . 80

Safety Cabinets . . . . . . . . . . . . . . . 80

Electrical Rooms . . . . . . . . . . . . . . 81

Rooms . . . . . . . . . . . . . . . . . . . . . . 81

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

TABLE OF CONTENTS

Isolation Rooms and Protective

Environment Rooms . . . . . . . . . . . . 82

Infection Isolation Rooms and

Protective Environment Rooms . . . 82

Ethylene Oxide (ETO) Sterilization Areas. . . . . . . . . . . . . . 82

Table 4-A Pressure Relationship and Ventilation Requirements

for General Acute Care

Hospitals, Skilled Nursing Facilities, Intermediate Care Facilities, Outpatient Facilities, Licensed Clinics, Correctional Treatment Centers, and Acute Psychiatric Hospitals . . . . . . . . . . . 84

Table 4-B Filter Efficiencies for Central

Ventilation and Air-Conditioning Systems In General Acute Care Hospitals, Outpatient Facilities,

Licensed Clinics and Acute

Psychiatric Hospitals . . . . . . . . . . . 91

Table 4-C Filter Efficiencies for Central

Ventilation and Air-Conditioning Systems In Skilled Nursing Facilities, Intermediate Care

Facilities and Correctional

Treatment Centers . . . . . . . . . . . . . 91

Table 402.1 Minimum Ventilation Rates in

Breathing Zone . . . . . . . . . . . . . . . . 92

Table 403.2.2 Zone Air Distribution Effectiveness. . 95

Table 403.7 Minimum Exhaust Rates. . . . . . . . . 96

CHAPTER 5 EXHAUST SYSTEMS . . . . . . . . . . 97

501.0 General. . . . . . . . . . . . . . . . . . . . . . 99

501.1 Applicability. . . . . . . . . . . . . . . . . . . 99

502.0 Termination. . . . . . . . . . . . . . . . . . . 99

502.1 Exhaust Opening Protection. . . . . . 99

502.2 Termination of Exhaust Ducts . . . . 99

Part I Environmental Air Ducts and

Product-Conveying Systems . . . . 99

503.0 Motors, Fans, and Filters . . . . . . . . 99

503.1 General. . . . . . . . . . . . . . . . . . . . . . 99

503.2 Fans . . . . . . . . . . . . . . . . . . . . . . . . 99

504.0 Environmental Air Ducts . . . . . . . . . 99

504.1 General. . . . . . . . . . . . . . . . . . . . . . 99

504.2 Independent Exhaust Systems. . . 100

504.3 Domestic Cooking Exhaust Equipment . . . . . . . . . . . . . . . . . . 100

504.4 Clothes Dryers . . . . . . . . . . . . . . . 100

504.5 Heat Recovery Ventilation (HRV) and Energy Recovery Ventilation (ERV) Systems . . . . . . 101

505.0 Product-Conveying Systems . . . . 101

505.1 General. . . . . . . . . . . . . . . . . . . . . 101

505.2 Incompatible Materials . . . . . . . . . 102

505.3 Flammability Limit. . . . . . . . . . . . . 102

505.4 Air-Moving Devices. . . . . . . . . . . . 102

505.5 Generating Flames, Sparks, or Hot Materials . . . . . . . . . . . . . . 102

505.6 Fire Dampers . . . . . . . . . . . . . . . . 102

505.7 Fire Detection, Smoke Control and Alarm Systems . . . . . . . . . . . . 102

505.8 Product-Conveying Duct Classifications. . . . . . . . . . . . . . . . 102

505.9 Minimum Velocities and

Circulation. . . . . . . . . . . . . . . . . . . 102

505.10 Makeup Air . . . . . . . . . . . . . . . . . . 102

505.11 Hoods and Enclosures . . . . . . . . . 103

Area of Parenteral Solutions . . . . 103

506.0 Product-Conveying Ducts. . . . . . . 103

506.1 Materials . . . . . . . . . . . . . . . . . . . . 103

Table 505.9 Range of Minimum Duct Design Velocities. . . . . . . . . . . . . . . . . . . . 103

Table 506.2(1) Minimum Sheet Metal Thickness for Round Ducts . . . . . . . . . . . . . . 104

506.2 Construction . . . . . . . . . . . . . . . . . 105

Table 506.2(2) Minimum Sheet Metal Thickness for Rectangular Ducts. . . . . . . . . . 106

506.3 Penetrations . . . . . . . . . . . . . . . . . 106

506.4 Condensate . . . . . . . . . . . . . . . . . 107

506.5 Fittings . . . . . . . . . . . . . . . . . . . . . 107

506.6 Explosion Venting. . . . . . . . . . . . . 107

506.7 Supports . . . . . . . . . . . . . . . . . . . . 107

506.8 Fire Protection . . . . . . . . . . . . . . . 107

506.9 Protection from Physical Damage . . . . . . . . . . . . . . . . . . . . 107

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

TABLE OF CONTENTS

506.10 Duct Clearances . . . . . . . . . . . . . . 107

Table 506.10.4 Basic Minimum Clearances to

Unprotected Surfaces. . . . . . . . . . 107

506.11 Clearance Reduction Methods . . . 108

Table 506.11 Reduction of Duct Clearance with

Specified Forms of Protection . . . 108

Part II Commercial Hoods and

Kitchen Ventilation . . . . . . . . . . . 109

507.0 General Requirements . . . . . . . . . 109

507.1 Exhaust Systems . . . . . . . . . . . . . 109

507.2 Type I Hood Exhaust System Requirements . . . . . . . . . . . . . . . . 109

507.3 Listed Devices . . . . . . . . . . . . . . . 109

507.4 Clearance . . . . . . . . . . . . . . . . . . . 109

507.5 Drawings. . . . . . . . . . . . . . . . . . . . 110

507.6 Notification of Change . . . . . . . . . 111

Exhaust Discharge . . . . . . . . . . . . 111

508.0 Type I Hoods . . . . . . . . . . . . . . . . 111

508.1 Where Required . . . . . . . . . . . . . . 111

508.2 Listed Type I Hood Assemblies . . 111

508.3 Construction of Type I Hoods . . . . 111

508.4 Supports . . . . . . . . . . . . . . . . . . . . 112

508.5 Hood Size . . . . . . . . . . . . . . . . . . . 112

Table 508.5.1.2 Extra-Heavy-Duty Cooking Appliance Airflow . . . . . . . . . . . . . 113

Table 508.5.1.3 Heavy-Duty Cooking Appliance

Airflow. . . . . . . . . . . . . . . . . . . . . . 113

Table 508.5.1.4 Medium-Duty Cooking Appliance

Airflow. . . . . . . . . . . . . . . . . . . . . . 113

Table 508.5.1.5 Light-Duty Cooking Appliance

Airflow. . . . . . . . . . . . . . . . . . . . . . 113

508.6 Solid-Fuel Hood Assemblies . . . . 114

508.7 Exhaust Outlets . . . . . . . . . . . . . . 114

509.0 Grease Removal Devices in

Hoods . . . . . . . . . . . . . . . . . . . . . . 114

509.1 Grease Removal Devices. . . . . . . 114

509.2 Installation . . . . . . . . . . . . . . . . . . 114

509.3 Solid-Fuel Grease Removal

Devices. . . . . . . . . . . . . . . . . . . . . 115

510.0 Exhaust Duct Systems . . . . . . . . . 115

510.1 General. . . . . . . . . . . . . . . . . . . . . 115

510.2 Clearance . . . . . . . . . . . . . . . . . . . 115

510.3 Openings . . . . . . . . . . . . . . . . . . . 115

510.4 Listed Grease Ducts . . . . . . . . . . . 116

510.5 Other Grease Ducts . . . . . . . . . . . 116

510.6 Exterior Installations . . . . . . . . . . . 117

510.7 Interior Installations . . . . . . . . . . . 118

510.8 Underground Installations. . . . . . . 118

510.9 Termination of Type I Hood Exhaust System . . . . . . . . . . . . . . 119

510.10 Solid-Fuel Duct Systems . . . . . . . 120

511.0 Air Movement . . . . . . . . . . . . . . . . 120

511.1 Exhaust Fans for Commercial

Cooking Operations . . . . . . . . . . . 120

511.2 Airflow. . . . . . . . . . . . . . . . . . . . . . 121

511.3 Makeup Air . . . . . . . . . . . . . . . . . . 122

511.4 Common Duct (Manifold) Systems . . . . . . . . . . . . . . . . . . . . 122

511.5 Solid-Fuel Air Movement

Requirements . . . . . . . . . . . . . . . . 122

512.0 Auxiliary Equipment . . . . . . . . . . . 122

512.1 Dampers . . . . . . . . . . . . . . . . . . . . 122

512.2 Electrical Equipment. . . . . . . . . . . 122

512.3 Other Equipment . . . . . . . . . . . . . 123

512.4 Solid-Fuel Auxiliary Equipment. . . 123

513.0 Fire-Extinguishing Equipment. . . . 123

513.1 General. . . . . . . . . . . . . . . . . . . . . 123

513.2 Types of Equipment . . . . . . . . . . . 123

513.3 Simultaneous Operation . . . . . . . . 124

513.4 Fuel and Electric Power Shutoff . . 125

513.5 Manual Actuation . . . . . . . . . . . . . 125

513.6 System Annunciation . . . . . . . . . . 125

513.7 Special Design and Application . . 125

513.8 Review and Certification. . . . . . . . 125

513.9 Installation Requirements . . . . . . . 125

513.10 Portable Fire Extinguishers . . . . . 125

513.11 Maintenance . . . . . . . . . . . . . . . . . 125

513.12 Solid-Fuel Fire-Extinguishing Equipment . . . . . . . . . . . . . . . . . . 126

514.0 Procedures for the Use, Inspection, Testing, and Maintenance of Equipment. . . . . . 126

514.1 Operating Procedures . . . . . . . . . 126

514.2 Inspection, Testing and Maintenance . . . . . . . . . . . . . . . . . 126

514.3 Inspection for Grease Buildup . . . 126

Table 514.3 Schedule of Inspection for Grease Buildup. . . . . . . . . . . . . . . 126

514.4 Cleaning of Exhaust Systems. . . . 126

514.5 Cooking Equipment Maintenance . 127

515.0 Minimum Safety Requirements for Cooking Equipment . . . . . . . . . 127

515.1 Cooking Equipment . . . . . . . . . . . 127

515.2 Operating Controls . . . . . . . . . . . . 128

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

TABLE OF CONTENTS

516.0 Recirculating Systems . . . . . . . . . 128

516.1 General Requirements . . . . . . . . . 128

516.2 Design Restrictions. . . . . . . . . . . . 128

516.3 Interlocks . . . . . . . . . . . . . . . . . . . 129

516.4 Location and Application Restrictions. . . . . . . . . . . . . . . . . . 129

516.5 Additional Fire Safety Requirements . . . . . . . . . . . . . . . . 129

516.6 Use and Maintenance. . . . . . . . . . 129

517.0 Solid-Fuel Cooking Operations. . . 129

517.1 Venting Application. . . . . . . . . . . . 129

517.2 Location of Appliances . . . . . . . . . 130

517.3 Hoods for Solid-Fuel Cooking. . . . 130

517.4 Exhaust Systems for Solid-Fuel Cooking . . . . . . . . . . . . 130

517.5 Grease Removal Devices

for Solid-Fuel Cooking . . . . . . . . . 130

517.6 Air Movement for Solid-Fuel

Cooking . . . . . . . . . . . . . . . . . . . . 130

517.7 Fire-Extinguishing Equipment for Solid-Fuel Cooking . . . . . . . . . 131

517.8 Other Safety Requirements . . . . . 131

518.0 Downdraft Appliances. . . . . . . . . . 131

518.1 General. . . . . . . . . . . . . . . . . . . . . 131

518.2 Ventilation System . . . . . . . . . . . . 132

518.3 Fire-Extinguishing Equipment. . . . 132

518.4 Airflow Switch or Transducer . . . . 132

518.5 Surface Materials . . . . . . . . . . . . . 132

519.0 Type II Hood Exhaust System Requirements . . . . . . . . . . . . . . . . 132

519.1 Where Required . . . . . . . . . . . . . . 132

519.2 Construction of Type II Hoods . . . 132

519.3 Type II Hood Exhaust System Net Airflow . . . . . . . . . . . . . . . . . . 132

519.4 Type II Exhaust Duct Systems . . . 132

519.5 Termination of Type II Hood Exhaust System . . . . . . . . . . . . . . 132

519.6 Makeup Air . . . . . . . . . . . . . . . . . . 133

519.7 Independent Exhaust Duct System . . . . . . . . . . . . . . . . . 133

CHAPTER 6 DUCT SYSTEMS . . . . . . . . . . . . . 135

601.0 General. . . . . . . . . . . . . . . . . . . . . 137

601.1 Applicability. . . . . . . . . . . . . . . . . . 137

601.2 Sizing Requirements . . . . . . . . . . 137

602.0 Material. . . . . . . . . . . . . . . . . . . . . 137

602.1 General. . . . . . . . . . . . . . . . . . . . . 137

602.2 Combustibles Within Ducts or

Plenums . . . . . . . . . . . . . . . . . . . . 137

602.3 Tall Wood (Mass Timber) Buildings . . . . . . . . . . . . . . . . . . . . 137

602.4 Metallic . . . . . . . . . . . . . . . . . . . . . 138

602.5 Nonmetallic Ducts. . . . . . . . . . . . . 138

602.6 Vibration Isolators. . . . . . . . . . . . . 138

602.7 Corridors. . . . . . . . . . . . . . . . . . . . 138

603.0 Installation of Ducts . . . . . . . . . . . 138

603.1 General. . . . . . . . . . . . . . . . . . . . . 138

603.2 Under-Floor or Crawl Space. . . . . 138

603.3 Metal Ducts. . . . . . . . . . . . . . . . . . 138

603.4 Flexible Air Ducts . . . . . . . . . . . . . 138

603.5 Plastic Ducts. . . . . . . . . . . . . . . . . 139

603.6 Protection of Ducts . . . . . . . . . . . . 139

603.7 Support of Ducts. . . . . . . . . . . . . . 139

603.8 Protection Against Flood Damage . 139

603.9 Joints and Seams of Ducts. . . . . . 139

Table 603.9.1 Closure Markings . . . . . . . . . . . . . 140

603.10 Cross Contamination . . . . . . . . . . 140

603.11 Underground Installation . . . . . . . 140

603.12 Air Dispersion Systems . . . . . . . . 140

603.13 Clearances . . . . . . . . . . . . . . . . . . 140

604.0 Furnace Plenums and Air Ducts

Used in Fuel-Gas Appliances . . . . 141

604.1 Furnace Plenums and Air Ducts. . 141

604.2 Supplied as a Part of Furnace . . . 141

604.3 Not Supplied with the Furnace . . . 141

604.4 Return Air . . . . . . . . . . . . . . . . . . . 141

605.0 Insulation of Ducts . . . . . . . . . . . . 141

605.1 General. . . . . . . . . . . . . . . . . . . . . 141

606.0 Smoke Dampers, Fire Dampers, and Ceiling Dampers . . . . . . . . . . 142

606.1 Smoke Dampers. . . . . . . . . . . . . . 142

606.2 Fire Dampers . . . . . . . . . . . . . . . . 142

606.3 Ceiling Radiation Dampers. . . . . . 142

606.4 Combination Fire/Smoke

Dampers . . . . . . . . . . . . . . . . . . . . 142

606.5 Corridor Dampers . . . . . . . . . . . . . 142

606.6 Periodic Testing and Inspection . . 142

606.7 Multiple Arrangements . . . . . . . . . 142

606.8 Access and Identification . . . . . . . 142

606.9 Freedom from Interference. . . . . . 142

606.10 Temperature Classification of Operating Elements . . . . . . . . . 142

607.0 Ventilating Ceilings . . . . . . . . . . . . 142

607.1 General. . . . . . . . . . . . . . . . . . . . . 142

607.2 Requirements . . . . . . . . . . . . . . . . 142

608.0 Use of Under-Floor Space as Supply Plenum for Dwelling Units. . 143

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

TABLE OF CONTENTS

608.1 General. . . . . . . . . . . . . . . . . . . . . 143

608.2 Dwelling Units. . . . . . . . . . . . . . . . 143

608.3 Enclosed. . . . . . . . . . . . . . . . . . . . 143

608.4 Flammable Materials . . . . . . . . . . 143

608.5 Access . . . . . . . . . . . . . . . . . . . . . 143

608.6 Automatic Control . . . . . . . . . . . . . 143

608.7 Temperature Limit . . . . . . . . . . . . 143

608.8 Noncombustible Receptacle. . . . . 143

608.9 Floor Registers . . . . . . . . . . . . . . . 143

608.10 Exterior Wall and Interior Stud

Partitions. . . . . . . . . . . . . . . . . . . . 143

608.11 Wall Register . . . . . . . . . . . . . . . . 143

608.12 Distance from Combustible . . . . . 143

608.13 Vapor Barrier . . . . . . . . . . . . . . . . 143

608.14 Prohibited . . . . . . . . . . . . . . . . . . . 143

609.0 Automatic Shutoffs . . . . . . . . . . . . 143

609.1 Air-Moving Systems and Smoke Detectors . . . . . . . . . . . . . . . . . . . 143

Smoke Detectors in Group I-2 Occupancies . . . . . . . . . . . . . . . . 144

CHAPTER 7 COMBUSTION AIR . . . . . . . . . . . 145

701.0 General. . . . . . . . . . . . . . . . . . . . . 147

701.1 Applicability. . . . . . . . . . . . . . . . . . 147

701.2 Pressure Difference . . . . . . . . . . . 147

701.3 Makeup Air . . . . . . . . . . . . . . . . . . 147

701.4 Indoor Combustion Air . . . . . . . . . 147

701.5 Indoor Opening Size and Location . . . . . . . . . . . . . . . . . . . . 147

701.6 Outdoor Combustion Air . . . . . . . . 147

701.7 Combination Indoor and Outdoor

Combustion Air . . . . . . . . . . . . . . . 148

701.8 Engineered Installations . . . . . . . . 149

701.9 Mechanical Combustion Air

Supply. . . . . . . . . . . . . . . . . . . . . . 149

701.10 Louvers, Grilles, and Screens . . . 149

701.11 Combustion Air Ducts. . . . . . . . . . 150

701.12 Dampers Prohibited . . . . . . . . . . . 150

702.0 Extra Device or Attachment . . . . . 150

702.1 General. . . . . . . . . . . . . . . . . . . . . 150

CHAPTER 8 CHIMNEYS AND VENTS. . . . . . . 151

801.0 General. . . . . . . . . . . . . . . . . . . . . 153

801.1 Applicability. . . . . . . . . . . . . . . . . . 153

801.2 Venting of Gas Appliances . . . . . . 153

801.3 Appliances Fueled by Other Fuels. 153

802.0 Venting of Appliances. . . . . . . . . . 153

802.1 Listing . . . . . . . . . . . . . . . . . . . . . . 153

802.2 Connection to Venting Systems . . 153

802.3 Minimum Safe Performance . . . . . 153

802.4 Type of Venting System to be Used . . . . . . . . . . . . . . . . . . . . . . . 154

802.5 Masonry, Metal, and Factory-Built Chimneys . . . . . . . . . . . . . . . . . . . 154

Table 802.4 Type of Venting System to be Used . . . . . . . . . . . . . . . . . . . . . . . 155

802.6 Gas Vents. . . . . . . . . . . . . . . . . . . 157

Table 802.6.1 Roof Slope Heights. . . . . . . . . . . . 158

802.7 Single-Wall Metal Pipe . . . . . . . . . 159

Table 802.7.3.3 Clearance for Connectors. . . . . . . 160

802.8 Through-the-Wall Vent Termination . . . . . . . . . . . . . . . . . . 160

802.9 Condensation Drain . . . . . . . . . . . 160

802.10 Vent Connectors for Category I Appliances . . . . . . . . . . . . . . . . . . 160

Table 802.10.1.3 Minimum Thickness for Galvanized

Steel Vent Connectors for Low Heat Appliances . . . . . . . . . . . . . . 161

Table 802.10.1.4 Minimum Thickness for Steel

Vent Connectors for Medium Heat Appliances . . . . . . . . . . . . . . 161

Table 802.8.1 Through-the-Wall Direct Vent Termination Clearances . . . . . . . . 162

802.11 Vent Connectors for Category II, Category III, and Category IV Appliances . . . . . . . . . . . . . . . . . . 164

802.12 Appliances Requiring Draft Hoods . . . . . . . . . . . . . . . . . . 164

802.13 Manually Operated Dampers . . . . 165

802.14 Automatically Operated Vent Dampers . . . . . . . . . . . . . . . . . . . . 165

802.15 Obstruction of Flow. . . . . . . . . . . . 165

803.0 Sizing of Category I Venting Systems . . . . . . . . . . . . . . . . . . . . 165

803.1 Additional Requirements to Single Appliance Vent . . . . . . . . . 165

803.2 Additional Requirements to Multiple-Appliance Vent.. . . . . . . . 167

Table 803.2.1 Vent Connector Maximum

Length. . . . . . . . . . . . . . . . . . . . . . 167

Table 803.1.2(1) Type B Double-Wall Gas Vent . . . 172

Table 803.1.2(2) Type B Double-Wall Gas Vent . . . 175

Table 803.1.2(3) Masonry Chimney. . . . . . . . . . . . . 177

Table 803.1.2(4) Masonry Chimney. . . . . . . . . . . . . 179

Table 803.1.2(5) Single-Wall Metal Pipe or Type B Asbestos-Cement Vent. . . . . . . . . 181

Table 803.1.2(6) Exterior Masonry Chimney . . . . . . 182

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

TABLE OF CONTENTS

Table 803.2(1) Type B Double-Wall Vent . . . . . . 183

Table 803.2(2) Type B Double-Wall Vent . . . . . . . 187

Table 803.2(3) Masonry Chimney. . . . . . . . . . . . . 189

Table 803.2(4) Masonry Chimney. . . . . . . . . . . . . 191

Table 803.2(5) Single-Wall Metal Pipe or Type B Asbestos-Cement Vent . . . 193

Table 803.2(6) Exterior Masonry Chimney . . . . . . 193

Table 803.2(7) Exterior Masonry Chimney . . . . . . 194

Table 803.2(8) Exterior Masonry Chimney . . . . . . 195

Table 803.2(9) Exterior Masonry Chimney . . . . . . 196

CHAPTER 9 INSTALLATION OF

SPECIFIC APPLIANCES. . . . . . . 197

901.0 General. . . . . . . . . . . . . . . . . . . . . 199

901.1 Applicability. . . . . . . . . . . . . . . . . . 199

902.0 General. . . . . . . . . . . . . . . . . . . . . 199

902.1 Nonindustrial Appliances . . . . . . . 199

902.2 Combustion Air from Bedroom

or Bathroom . . . . . . . . . . . . . . . . . 199

902.3 Added or Converted Appliances. . 199

902.4 Type of Gas(es) . . . . . . . . . . . . . . 199

902.5 Safety Shutoff Devices for Unlisted LP-Gas Appliances Used Indoors . . . . . . . . . . . . . . . . 199

902.6 Fuel Input Rate . . . . . . . . . . . . . . . 199

902.7 Use of Air or Oxygen Under Pressure . . . . . . . . . . . . . . . . . . . . 199

902.8 Appliance Support . . . . . . . . . . . . 199

902.9 Flammable Vapors . . . . . . . . . . . . 199

902.10 Solid-Fuel-Burning Appliances . . . 199

902.11 Combination of Appliances and Equipment . . . . . . . . . . . . . . . 199

902.12 Protection of Gas Appliances from Fumes or Gases Other

than Products of Combustion . . . . 199

902.13 Process Air . . . . . . . . . . . . . . . . . . 200

902.14 Gas Appliance Pressure Regulators . . . . . . . . . . . . . . . . . . 200

902.15 Bleed Lines for Diaphragm-Type Valves. . . . . . . . . . . . . . . . . . . . . . 200

903.0 Air-Conditioning Appliances . . . . . 200

903.1 Electric Air Conditioners . . . . . . . . 200

903.2 Gas-Fired Air Conditioners

and Heat Pumps. . . . . . . . . . . . . . 200

903.3 Packaged Terminal Air Conditioners . . . . . . . . . . . . . . . . . 200

904.0 Central Heating Boilers and Furnaces. . . . . . . . . . . . . . . . . . . . 200

904.1 Application . . . . . . . . . . . . . . . . . . 200

904.2 Location . . . . . . . . . . . . . . . . . . . . 201

904.3 Clearance . . . . . . . . . . . . . . . . . . . 201

904.4 Assembly and Installation. . . . . . . 201

904.5 Temperature or Pressure Limiting Devices . . . . . . . . . . . . . . 202

904.6 Low-Water Cutoff . . . . . . . . . . . . . 202

904.7 Steam Safety and Pressure Relief Valves. . . . . . . . . . . . . . . . . 202

904.8 Refrigeration Coils . . . . . . . . . . . . 202

904.9 Cooling Units Used with Heating Boilers. . . . . . . . . . . . . . . . . . . . . . 202

904.10 Furnace (Upright and Horizontal) . . 202

Table 904.3.2 Clearances to Combustible

Material for Unlisted Furnaces

and Boilers . . . . . . . . . . . . . . . . . . 202

904.11 Solid-Fuel-Fired Furnaces . . . . . . 203

904.12 Oil-Fired Central Furnaces . . . . . . 203

904.13 Commercial or Industrial

Gas Heaters . . . . . . . . . . . . . . . . . 203

904.14 Electric Central Furnaces . . . . . . . 203

905.0 Duct Furnaces . . . . . . . . . . . . . . . 203

905.1 Application . . . . . . . . . . . . . . . . . . 203

905.2 Clearances . . . . . . . . . . . . . . . . . . 203

905.3 Installation of Duct Furnaces. . . . . 203

905.4 Access Panels . . . . . . . . . . . . . . . 203

905.5 Location of Draft Hoods

and Controls . . . . . . . . . . . . . . . . . 203

905.6 Circulating Air . . . . . . . . . . . . . . . . 203

905.7 Duct Furnaces Used with

Refrigeration Systems . . . . . . . . . 203

905.8 Installation in Commercial

Garages and Aircraft Hangars . . . 203

905.9 Electric Duct Heaters . . . . . . . . . . 203

906.0 Floor Furnaces . . . . . . . . . . . . . . . 203

906.1 Application . . . . . . . . . . . . . . . . . . 203

906.2 Installation . . . . . . . . . . . . . . . . . . 204

906.3 Temperature Limit Controls . . . . . 204

906.4 Combustion and Circulating Air. . . 204

906.5 Placement. . . . . . . . . . . . . . . . . . . 204

906.6 Bracing . . . . . . . . . . . . . . . . . . . . . 204

906.7 Support . . . . . . . . . . . . . . . . . . . . . 204

906.8 Clearance . . . . . . . . . . . . . . . . . . . 204

906.9 Access . . . . . . . . . . . . . . . . . . . . . 204

906.10 Seepage Pan . . . . . . . . . . . . . . . . 204

906.11 Wind Protection . . . . . . . . . . . . . . 204

906.12 Upper Floor Installations. . . . . . . . 204

906.13 First Floor Installation . . . . . . . . . . 204

906.14 Oil-Fired Floor Furnaces. . . . . . . . 204

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

TABLE OF CONTENTS

907.0 Wall Furnaces. . . . . . . . . . . . . . . . 204

907.1 Application . . . . . . . . . . . . . . . . . . 204

907.2 Installation . . . . . . . . . . . . . . . . . . 204

907.3 Location . . . . . . . . . . . . . . . . . . . . 205

907.4 Combustion and Circulating Air . . 205

907.5 Oil-Fired Wall Furnaces . . . . . . . . 205

908.0 Clothes Dryers . . . . . . . . . . . . . . . 205

908.1 Application . . . . . . . . . . . . . . . . . . 205

908.2 Electric Clothes Dryers . . . . . . . . . 205

908.3 Gas-Fired Clothes Dryers. . . . . . . 205

909.0 Conversion Burners . . . . . . . . . . . 205

909.1 General. . . . . . . . . . . . . . . . . . . . . 205

910.0 Burner Assemblies . . . . . . . . . . . . 206

910.1 Oil Burners . . . . . . . . . . . . . . . . . . 206

910.2 Gas Burners . . . . . . . . . . . . . . . . . 206

911.0 Decorative Appliances for Installation in Vented Fireplaces. . . 206

911.1 Application . . . . . . . . . . . . . . . . . . 206

911.2 Prohibited Installations . . . . . . . . . 206

911.3 Installation . . . . . . . . . . . . . . . . . . 206

911.4 Fireplace Screens. . . . . . . . . . . . . 206

912.0 Gas Fireplaces, Vented . . . . . . . . 206

912.1 Application . . . . . . . . . . . . . . . . . . 206

912.2 Reserved . . . . . . . . . . . . . . . . . . . 206

912.3 Installation . . . . . . . . . . . . . . . . . . 206

912.4 Combustion and Circulating Air . . . 206

913.0 Factory-Built Fireplaces and Fireplace Stoves. . . . . . . . . . . . . . 206

913.1 Factory-Built Fireplaces . . . . . . . . 206

913.2 Fireplace Stoves. . . . . . . . . . . . . . 206

913.3 Fireplace Accessories . . . . . . . . . 206

914.0 Non-Recirculating Direct Gas-Fired Industrial Air Heaters. . . 206

914.1 Application . . . . . . . . . . . . . . . . . . 206

914.2 Prohibited Installations . . . . . . . . . 206

914.3 Installation . . . . . . . . . . . . . . . . . . 206

914.4 Clearance from Combustible

Materials . . . . . . . . . . . . . . . . . . . . 207

914.5 Air Supply . . . . . . . . . . . . . . . . . . . 207

914.6 Atmospheric Vents, Gas Reliefs, or Bleeds . . . . . . . . . . . . . 207

914.7 Relief Openings . . . . . . . . . . . . . . 207

914.8 Purging . . . . . . . . . . . . . . . . . . . . . 207

915.0 Room Heaters . . . . . . . . . . . . . . . 207

915.1 Application . . . . . . . . . . . . . . . . . . 207

915.2 Electric Room Heaters . . . . . . . . . 207

915.3 Gas-Fired Room Heaters . . . . . . . 207

915.4 Solid-Fuel Type Room Heaters . . 208

916.0 Unit Heaters . . . . . . . . . . . . . . . . . 208

916.1 Application . . . . . . . . . . . . . . . . . . 208

916.2 Support . . . . . . . . . . . . . . . . . . . . 208

916.3 Clearance for Suspended-Type Unit Heaters . . . . . . . . . . . . . . . . . 208

916.4 Combustion and Circulating Air. . . 208

916.5 Ductwork. . . . . . . . . . . . . . . . . . . . 208

916.6 Installation in Commercial

Garages and Aircraft Hangars . . . 208

916.7 Oil-Fired Unit Heaters. . . . . . . . . . 208

917.0 Food Service Appliance, FloorMounted . . . . . . . . . . . . . . . . . . . . 208

917.1 Application . . . . . . . . . . . . . . . . . . 208

917.2 Clearance for Listed Appliances. . . 208

917.3 Mounting on Combustible Floors . . . . . . . . . . . . . . . . . . . . . . 208

917.4 Installation on Noncombustible

Floors . . . . . . . . . . . . . . . . . . . . . . 209

917.5 Combustible Material

Adjacent to Cooking Top . . . . . . . 209

917.6 Use with Casters . . . . . . . . . . . . . 209

917.7 Level Installation. . . . . . . . . . . . . . 209

917.8 Ventilation. . . . . . . . . . . . . . . . . . . 209

918.0 Food Service Appliances, Counter Appliances . . . . . . . . . . . 209

918.1 Application . . . . . . . . . . . . . . . . . . 209

918.2 Vertical Clearance . . . . . . . . . . . . 209

918.3 Clearance for Listed Appliances. . . 209

918.4 Clearance for Unlisted

Appliances . . . . . . . . . . . . . . . . . . 209

919.0 Household Cooking Appliances. . . 209

919.1 Application . . . . . . . . . . . . . . . . . . 209

919.2 Electric Household Cooking Appliances . . . . . . . . . . . . . . . . . . 209

919.3 Gas-Fired Household Cooking Appliances . . . . . . . . . . . . . . . . . . 209

919.4 Floor-Mounted Units . . . . . . . . . . . 210

919.5 Built-In Units . . . . . . . . . . . . . . . . . 210

919.6 Level Installation. . . . . . . . . . . . . . 210

920.0 Cooking Appliance Listings . . . . . 210

920.1 Commercial Electric Ranges . . . . 210

920.2 Commercial Wood-Fired

Baking Ovens . . . . . . . . . . . . . . . . 210

920.3 Oil-Burning Ranges . . . . . . . . . . . 210

921.0 Open-Top Broiler Units. . . . . . . . . 210

921.1 Application . . . . . . . . . . . . . . . . . . 210

921.2 Protection Above Domestic Units. . 210

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

TABLE OF CONTENTS

921.3 Commercial Units . . . . . . . . . . . . . 210

922.0 Outdoor Cooking Appliances . . . . 210

922.1 Application . . . . . . . . . . . . . . . . . . 210

923.0 Illuminating Appliances. . . . . . . . . 211

923.1 Clearances for Listed Appliances. . 211

923.2 Clearances for Unlisted

Appliances . . . . . . . . . . . . . . . . . . 211

Table 923.2.1 Clearances for Unlisted Outdoor

Open-Flame Illuminating Appliances . . . . . . . . . . . . . . . . . . 211

923.3 Mounting on Buildings . . . . . . . . . 211

923.4 Mounting on Posts . . . . . . . . . . . . 211

923.5 Appliance Pressure Regulators . . . 211

924.0 Incinerators and Crematories . . . . 211

924.1 Field Constructed Commercial Industrial Incinerators . . . . . . . . . . 211

924.2 Factory-Built Commercial Crematories . . . . . . . . . . . . . . . . . 211

924.3 Residential Incinerators . . . . . . . . 211

925.0 Infrared Heaters . . . . . . . . . . . . . . 211

925.1 Application . . . . . . . . . . . . . . . . . . 211

925.2 Support . . . . . . . . . . . . . . . . . . . . . 211

925.3 Clearance . . . . . . . . . . . . . . . . . . . 211

925.4 Combustion and Ventilation Air . . . 212

925.5 Installation in Commercial

Garages and Aircraft Hangars . . . 212

925.6 Electric Radiant Heaters. . . . . . . . 212

926.0 Pool Heaters. . . . . . . . . . . . . . . . . 212

926.1 Application . . . . . . . . . . . . . . . . . . 212

926.2 Location . . . . . . . . . . . . . . . . . . . . 212

926.3 Clearance . . . . . . . . . . . . . . . . . . . 212

926.4 Temperature or PressureLimiting Devices . . . . . . . . . . . . . . 212

926.5 Bypass Valves . . . . . . . . . . . . . . . 212

926.6 Venting . . . . . . . . . . . . . . . . . . . . . 212

927.0 Refrigerators. . . . . . . . . . . . . . . . . 212

927.1 Application . . . . . . . . . . . . . . . . . . 212

927.2 Clearance . . . . . . . . . . . . . . . . . . . 212

927.3 Venting or Ventilating Kits Approved for Use with a Refrigerator. . . . . . . . . . . . . . . . . . 212

928.0 Gas-Fired Toilets . . . . . . . . . . . . . 212

928.1 Clearance . . . . . . . . . . . . . . . . . . . 212

928.2 Installation on Combustible

Floors . . . . . . . . . . . . . . . . . . . . . . 212

928.3 Vents . . . . . . . . . . . . . . . . . . . . . . 212

929.0 Appliances for Installation in Manufactured Housing . . . . . . . 212

929.1 General. . . . . . . . . . . . . . . . . . . . . 212

930.0 Small Ceramic Kilns . . . . . . . . . . . 212

930.1 General. . . . . . . . . . . . . . . . . . . . . 212

930.2 Installation . . . . . . . . . . . . . . . . . . 212

930.3 Fuel-Gas Controls . . . . . . . . . . . . 212

930.4 Electrical Equipment. . . . . . . . . . . 212

930.5 Installations Inside Buildings . . . . 213

930.6 Exterior Installations . . . . . . . . . . . 213

931.0 Outdoor Open Flame Decorative Appliances . . . . . . . . . 213

931.1 General. . . . . . . . . . . . . . . . . . . . . 213

932.0 Evaporative Cooling Systems. . . . 213

932.1 General. . . . . . . . . . . . . . . . . . . . . 213

932.2 Location . . . . . . . . . . . . . . . . . . . . 213

932.3 Access, Inspection, and Repair. . . 213

932.4 Installation . . . . . . . . . . . . . . . . . . 213

933.0 Refrigeration Appliances . . . . . . . 213

933.1 Self-Contained Refrigerators and Freezers . . . . . . . . . . . . . . . . 213

933.2 Unit Coolers . . . . . . . . . . . . . . . . . 214

933.3 Self-Contained Mechanical

Refrigeration Systems . . . . . . . . . 214

934.0 Ductless Mini-Split Systems Installation . . . . . . . . . . . . . . . . . . 214

934.1 General. . . . . . . . . . . . . . . . . . . . . 214

935.0 Air Filter Appliances . . . . . . . . . . . 214

935.1 Electrostatic Air Cleaners . . . . . . . 214

935.2 High-Efficiency Particulate Air Filter Units . . . . . . . . . . . . . . . . 214

936.0 Gaseous Hydrogen Systems . . . . 214

936.1 General. . . . . . . . . . . . . . . . . . . . . 214

937.0 Compressed Natural Gas (CNG) Vehicular Fuel Systems . . . . . . . . 214

937.1 General. . . . . . . . . . . . . . . . . . . . . 214

938.0 Dehumidifiers . . . . . . . . . . . . . . . . 214

938.1 General. . . . . . . . . . . . . . . . . . . . . 214

939.0 Sauna Heaters . . . . . . . . . . . . . . . 214

939.1 Electric Sauna Heaters. . . . . . . . . 214

CHAPTER 10 BOILERS AND

PRESSURE VESSELS . . . . . . . . 215

1001.0 General. . . . . . . . . . . . . . . . . . . . . 217

1001.1 Applicability. . . . . . . . . . . . . . . . . . 217

1001.2 Boiler Rooms and Enclosures . . . 217

1001.3 Air for Combustion

and Ventilation . . . . . . . . . . . . . . . 217

1001.4 Drainage . . . . . . . . . . . . . . . . . . . . 217

1001.5 Mounting. . . . . . . . . . . . . . . . . . . . 217

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

TABLE OF CONTENTS

1001.6 Chimneys or Vents . . . . . . . . . . . . 217

1002.0 Standards . . . . . . . . . . . . . . . . . . . 217

1002.1 General. . . . . . . . . . . . . . . . . . . . . 217

1002.2 Oil-Burning Boilers . . . . . . . . . . . . 217

1002.3 Electric Boilers . . . . . . . . . . . . . . . 217

1002.4 Solid-Fuel-Fired Boilers . . . . . . . . 217

1002.5 Dual Purpose Water Heaters . . . . 217

1003.0 Detailed Requirements . . . . . . . . . 218

1003.1 Safety Requirements . . . . . . . . . . 218

1003.2 Controls . . . . . . . . . . . . . . . . . . . . 218

1003.3 Gauges . . . . . . . . . . . . . . . . . . . . . 218

1003.4 Stack Dampers . . . . . . . . . . . . . . . 218

1003.5 Welding. . . . . . . . . . . . . . . . . . . . . 218

1004.0 Expansion Tanks . . . . . . . . . . . . . 218

1004.1 General. . . . . . . . . . . . . . . . . . . . . 218

1004.2 Open-Type Expansion Tanks . . . . 218

1004.3 Closed-Type Systems . . . . . . . . . 218

1004.4 Minimum Capacity of ClosedType Tank. . . . . . . . . . . . . . . . . . . 218

Table 1004.4(1) Expansion Tank Capacities for Gravity Hot Water Systems . . . . . 219

Table 1004.4(2) Expansion Tank Capacities for Forced Hot Water Systems . . . . . 219

1005.0 Safety or Relief Valve Discharge . . 219

1005.1 General. . . . . . . . . . . . . . . . . . . . . 219

1005.2 Discharge Piping . . . . . . . . . . . . . 219

1005.3 Splash Shield . . . . . . . . . . . . . . . . 219

1005.4 Hazardous Discharge . . . . . . . . . . 219

1005.5 Vacuum Relief Valve . . . . . . . . . . 219

1006.0 Shutoff Valves . . . . . . . . . . . . . . . 219

1006.1 General. . . . . . . . . . . . . . . . . . . . . 219

1007.0 Gas-Pressure Regulators . . . . . . . 219

1007.1 General. . . . . . . . . . . . . . . . . . . . . 219

1008.0 Low-Water Cutoff . . . . . . . . . . . . . 220

1008.1 General. . . . . . . . . . . . . . . . . . . . . 220

1009.0 Combustion Regulators Safety Valves . . . . . . . . . . . . . . . . 220

1009.1 General. . . . . . . . . . . . . . . . . . . . . 220

1010.0 Clearance for Access . . . . . . . . . . 220

1010.1 General. . . . . . . . . . . . . . . . . . . . . 220

1010.2 Power Boilers . . . . . . . . . . . . . . . . 220

1010.3 Steam-Heating Boilers, Hot Water Boilers, and Power Boilers. . 220

1010.4 Package Boilers, Steam-Heating Boilers, and Hot-Water-Heating Boilers. . . . . . . . . . . . . . . . . . . . . . 220

1011.0 Boilers, Stokers, and Steam

Generators . . . . . . . . . . . . . . . . . . 220

1011.1 General. . . . . . . . . . . . . . . . . . . . . 220

1012.0 Operating Adjustments and Instructions . . . . . . . . . . . . . . . . . . 220

1012.1 General. . . . . . . . . . . . . . . . . . . . . 220

1013.0 Inspections and Tests. . . . . . . . . . 220

1013.1 General. . . . . . . . . . . . . . . . . . . . . 220

1013.2 Operating Permit . . . . . . . . . . . . . 221

1013.3 Maintenance Inspection . . . . . . . . 221

1013.4 Power and Miniature Boilers. . . . . 221

1013.5 Steam-Heating and WaterHeating Boilers . . . . . . . . . . . . . . . 221

1013.6 Automatic Steam-Heating Boilers. . . . . . . . . . . . . . . . . . . . . . 221

1013.7 Unfired Pressure Vessels . . . . . . . 221

1014.0 Operation and Maintenance of

Boilers and Pressure Vessels. . . . 221

1014.1 General. . . . . . . . . . . . . . . . . . . . . 221

Table 1003.2.1 Controls and Limit Devices for

Automatic Boilers . . . . . . . . . . . . . 222

CHAPTER 11 REFRIGERATION . . . . . . . . . . . . 225

1101.0 General. . . . . . . . . . . . . . . . . . . . . 227

1101.1 Applicability. . . . . . . . . . . . . . . . . . 227

1101.2 Equipment . . . . . . . . . . . . . . . . . . 227

Part I Refrigeration Systems . . . . . . . . 227

1102.0 Refrigeration Systems . . . . . . . . . 227

1102.1 General. . . . . . . . . . . . . . . . . . . . . 227

1102.2 Ammonia Refrigeration Systems . . 227

1102.3 Refrigerants . . . . . . . . . . . . . . . . . 227

1103.0 Classification . . . . . . . . . . . . . . . . 227

1103.1 Classification of Refrigerants . . . . 227

Table 1103.1.1 Refrigerant Safety Group Classifications. . . . . . . . . . . . . . . . 227

1103.2 Classification of Refrigeration Systems . . . . . . . . . . . . . . . . . . . . 227

1103.3 Higher Flammability Refrigerants . . . . . . . . . . . . . . . . . 227

1104.0 Requirements for Refrigerant and Refrigeration System Use . . . 227

1104.1 System Selection . . . . . . . . . . . . . 227

1104.2 Refrigerant Concentration Limit (RCL) . . . . . . . . . . . . . . . . . . 227

Table 1104.1 Permissible Refrigeration Systems . . . . . . . . . . . . . . . . . . . . 228

1104.3 Institutional Occupancies . . . . . . . 229

1104.4 Industrial Occupancies and Refrigerated Rooms . . . . . . . . . . . 229

1104.5 Flammable Refrigerants . . . . . . . . 229

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

TABLE OF CONTENTS

1104.6 Group A2L Refrigerants for Human Comfort . . . . . . . . . . . . . . 229

110.4.7 Applications for Human Comfort and for Nonindustrial

Occupancies. . . . . . . . . . . . . . . . . 230

1104.8 Refrigerant Type and Purity . . . . . 230

1104.9 Changing Refrigerants . . . . . . . . . 231

1105.0 General Requirements . . . . . . . . . 231

1105.1 Human Comfort . . . . . . . . . . . . . . 231

1105.2 Supports and Anchorage . . . . . . . 231

1105.3 Access . . . . . . . . . . . . . . . . . . . . . 231

1105.4 Illumination and Service

Receptacles . . . . . . . . . . . . . . . . . 231

1105.5 Ventilation of Rooms

Containing Condensing Units . . . . 231

1105.6 Prohibited Locations . . . . . . . . . . . 232

1105.7 Condensate . . . . . . . . . . . . . . . . . 232

1105.8 Defrost . . . . . . . . . . . . . . . . . . . . . 232

1105.9 Overflows . . . . . . . . . . . . . . . . . . . 232

1105.10 Condensate, Defrost, and Overflow Disposal. . . . . . . . . . . . . 232

1105.11 Refrigerant Port Protection . . . . . . 232

1105.12 Storage . . . . . . . . . . . . . . . . . . . . . 232

1106.0 Refrigeration Machinery Rooms . . 232

1106.1 Where Required . . . . . . . . . . . . . . 232

1106.2 Refrigeration Machinery Room, General Requirements . . . . . . . . . 232

1106.3 Normal Operation . . . . . . . . . . . . . 233

1106.4 Natural Ventilation . . . . . . . . . . . . 234

1106.5 Combustion Air . . . . . . . . . . . . . . . 234

1106.6 Ventilation Intake . . . . . . . . . . . . . 234

1106.7 Maximum Temperature . . . . . . . . 234

1106.8 Refrigerant Parts in Air Duct. . . . . 234

1106.9 Dimensions. . . . . . . . . . . . . . . . . . 234

1106.10 Exits . . . . . . . . . . . . . . . . . . . . . . . 234

1106.11 Machinery Room, A2L and B2L . . 234

Table 1106.11.10.2 Refrigerant Detector Set Points, Response Times, Alarms, and Ventilation Levels . . . . . . . . . . . . . 235

Table 1106.11.11.2 Level 1 Ventilation Rate for

Class 2L Refrigerants . . . . . . . . . . . 236

1107.0 Machinery Room, Special Requirements . . . . . . . . . . . . . . . . 236

1107.1 General. . . . . . . . . . . . . . . . . . . . . 236

1108.0 Refrigeration Machinery Room Equipment and Controls . . . . . . . . 237

1108.1 General. . . . . . . . . . . . . . . . . . . . . 237

1108.2 Electrical . . . . . . . . . . . . . . . . . . . . 237

1108.3 Emergency Shutoff . . . . . . . . . . . . 237

1108.4 Installation, Maintenance, and Testing . . . . . . . . . . . . . . . . . . . . . 237

1108.5 Emergency Pressure Control System . . . . . . . . . . . . . . . . . . . . . 237

1109.0 Refrigeration Piping, Containers, and Valves . . . . . . . . . . . . . . . . . . 237

1109.1 Materials . . . . . . . . . . . . . . . . . . . . 237

Table 1109.1 Materials for Refrigerant Piping, Tubing, and Fittings . . . . . . . . . . . 239

1109.2 Joints . . . . . . . . . . . . . . . . . . . . . . 239

1109.3 Penetration of Piping . . . . . . . . . . 239

1109.4 Location of Refrigeration Piping . . 239

1109.5 Underground Piping . . . . . . . . . . . 239

1109.6 Support . . . . . . . . . . . . . . . . . . . . . 239

1109.7 Pipe Enclosure . . . . . . . . . . . . . . . 239

1109.8 Visual Inspection . . . . . . . . . . . . . 240

1109.9 Condensation . . . . . . . . . . . . . . . . 240

1109.10 Identification . . . . . . . . . . . . . . . . . 240

1110.0 Valves. . . . . . . . . . . . . . . . . . . . . . 240

1110.1 More than 6.6 Pounds of

Refrigerant . . . . . . . . . . . . . . . . . . 240

1110.2 More than 110 Pounds of

Refrigerant . . . . . . . . . . . . . . . . . . 240

1110.3 Support . . . . . . . . . . . . . . . . . . . . . 240

1110.4 Access . . . . . . . . . . . . . . . . . . . . . 240

1110.5 Identification . . . . . . . . . . . . . . . . . 240

1111.0 Pressure-Limiting Devices . . . . . . 240

1111.1 Where Required . . . . . . . . . . . . . . 240

1111.2 Setting . . . . . . . . . . . . . . . . . . . . . 240

1111.3 Location . . . . . . . . . . . . . . . . . . . . 240

1111.4 Emergency Stop . . . . . . . . . . . . . . 240

1112.0 Pressure-Relief Devices . . . . . . . . 241

1112.1 General. . . . . . . . . . . . . . . . . . . . . 241

1112.2 Positive Displacement Compressor . . . . . . . . . . . . . . . . . 241

1112.3 Liquid-Containing Portions of Systems . . . . . . . . . . . . . . . . . . 241

1112.4 Evaporators . . . . . . . . . . . . . . . . . 241

1112.5 Hydrostatic Expansion . . . . . . . . . 241

1112.6 Actuation. . . . . . . . . . . . . . . . . . . . 242

1112.7 Stop Valves Prohibited . . . . . . . . . 242

1112.8 Location . . . . . . . . . . . . . . . . . . . . 242

1112.9 Materials . . . . . . . . . . . . . . . . . . . . 242

1112.10 Pressure-Relief Valve Setting . . . . 242

1112.11 Discharge from Pressure-Relief Devices. . . . . . . . . . . . . . . . . . . . . 242

1112.12 Discharge Piping . . . . . . . . . . . . . 243

Table 1112.12.4 Atmospheric Pressure at Nominal

Installation Elevation. . . . . . . . . . . 244

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

TABLE OF CONTENTS

1112.13 Rating of Pressure-Relief Device. . . . . . . . . . . . . . . . . . . . . . 244

1112.14 Rating of Rupture Members and Fusible Plugs . . . . . . . . . . . . . . . . 244

1113.0 Overpressure Protection. . . . . . . . 244

1113.1 General. . . . . . . . . . . . . . . . . . . . . 244

1113.2 Type of Protection . . . . . . . . . . . . 245

1113.3 Discharging into Lowside of System . . . . . . . . . . . . . . . . . . . . . 245

1113.4 Parallel Pressure-Relief Devices . . 245

1113.5 Discharge Capacity . . . . . . . . . . . 245

1113.6 Three-Way Valve . . . . . . . . . . . . . 245

1114.0 Special Discharge Requirements. . 245

1114.1 General. . . . . . . . . . . . . . . . . . . . . 245

1114.2 Design Requirements . . . . . . . . . . 245

1114.3 Testing . . . . . . . . . . . . . . . . . . . . . 245

1115.0 Labeling and Identification . . . . . . 245

1115.1 General. . . . . . . . . . . . . . . . . . . . . 245

1115.2 Volume and Type . . . . . . . . . . . . . 245

1115.3 Permanent Sign . . . . . . . . . . . . . . 245

1115.4 Marking of Pressure-Relief Devices. . . . . . . . . . . . . . . . . . . . . 245

1115.5 Nameplate . . . . . . . . . . . . . . . . . . 245

1116.0 Testing of Refrigeration Equipment . . . . . . . . . . . . . . . . . . 246

1116.1 Factory Tests . . . . . . . . . . . . . . . . 246

1116.2 Field Tests . . . . . . . . . . . . . . . . . . 246

1116.3 Test Gases . . . . . . . . . . . . . . . . . . 246

1116.4 Declaration . . . . . . . . . . . . . . . . . . 246

1116.5 Brine Systems . . . . . . . . . . . . . . . 247

1117.0 Refrigerant-Containing Pressure Vessels . . . . . . . . . . . . . . . . . . . . . 247

1117.1 Inside Dimensions 6 Inches

or Less . . . . . . . . . . . . . . . . . . . . . 247

1117.2 Inside Dimensions More than

6 Inches . . . . . . . . . . . . . . . . . . . . 247

1117.3 Pressure Vessels for 15 psig or Less . . . . . . . . . . . . . . . . . . . . . 247

1118.0 Maintenance and Operation . . . . . 247

1118.1 General. . . . . . . . . . . . . . . . . . . . . 247

Part II Cooling Towers . . . . . . . . . . . . . . 247

1119.0 General. . . . . . . . . . . . . . . . . . . . . 247

1119.1 Applicability. . . . . . . . . . . . . . . . . . 247

1120.0 Support and Anchorage . . . . . . . . 247

1120.1 General. . . . . . . . . . . . . . . . . . . . . 247

1121.0 Drainage . . . . . . . . . . . . . . . . . . . . 247

1121.1 General. . . . . . . . . . . . . . . . . . . . . 247

1122.0 Chemical Treatment Systems . . . 247

1122.1 General. . . . . . . . . . . . . . . . . . . . . 247

1122.2 Automated Control of Cycles of Concentration . . . . . . . . . . . . . . . . 247

1123.0 Location . . . . . . . . . . . . . . . . . . . . 247

1123.1 General. . . . . . . . . . . . . . . . . . . . . 247

1124.0 Electrical . . . . . . . . . . . . . . . . . . . . 247

1124.1 General. . . . . . . . . . . . . . . . . . . . . 247

1125.0 Refrigerants and Hazardous

Fluids . . . . . . . . . . . . . . . . . . . . . . 247

1125.1 General. . . . . . . . . . . . . . . . . . . . . 247

1126.0 Drift Eliminators . . . . . . . . . . . . . . 248

1126.1 General. . . . . . . . . . . . . . . . . . . . . 248

1127.0 Water Supply . . . . . . . . . . . . . . . . 248

1127.1 General . . . . . . . . . . . . . . . . . . . . 248

Table 1102.3 Refrigerant Groups, Properties, and Allowable Quantities . . . . . . . 249

CHAPTER 12 HYDRONICS . . . . . . . . . . . . . . . . 255

1201.0 General. . . . . . . . . . . . . . . . . . . . . 257

1201.1 Applicability. . . . . . . . . . . . . . . . . . 257

1201.2 Insulation . . . . . . . . . . . . . . . . . . . 257

1201.3 Water Hammer Protection . . . . . . 257

1201.4 Terminal Units . . . . . . . . . . . . . . . 257

1201.5 Return-Water Low-Temperature

Protection . . . . . . . . . . . . . . . . . . . 257

1201.6 Heat Transfer Fluid Quality. . . . . . 257

1201.7 Heat Emitters . . . . . . . . . . . . . . . . 257

1201.8 Mechanical Devices . . . . . . . . . . . 257

1201.9 Flexible Connectors . . . . . . . . . . . 257

1201.10 Freeze Protection . . . . . . . . . . . . . 257

Table 1201.10 Percent Glycol Mixtures . . . . . . . . 257

1202.0 Protection of Potable Water

Supply. . . . . . . . . . . . . . . . . . . . . . 257

1202.1 Prohibited Sources . . . . . . . . . . . . 257

1202.2 Chemical Injection . . . . . . . . . . . . 257

1202.3 Compatibility . . . . . . . . . . . . . . . . . 258

1203.0 Capacity of Heat Source. . . . . . . . 258

1203.1 Heat Source . . . . . . . . . . . . . . . . . 258

1203.2 Dual Purpose Water Heaters . . . . 258

Table 1203.2 Water Heaters . . . . . . . . . . . . . . . 258

1203.3 Tankless Water Heaters . . . . . . . 258

1204.0 Identification of Potable and

Nonpotable Water Systems . . . . . 258

1204.1 General. . . . . . . . . . . . . . . . . . . . . 258

1204.2 Color and Information . . . . . . . . . . 258

1204.3 Potable Water. . . . . . . . . . . . . . . . 258

1204.4 Nonpotable Water. . . . . . . . . . . . . 258

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

TABLE OF CONTENTS

Table 1204.3 Minimum Length of Color Field and Size of Letters. . . . . . . . 258

1204.5 Location of Piping Identification . . . 258

1204.6 Flow Directions . . . . . . . . . . . . . . . 258

1204.7 Heat Transfer Fluid. . . . . . . . . . . . 258

1204.8 Identification of Chemical

Additives . . . . . . . . . . . . . . . . . . . . 258

1205.0 Installation, Testing, and Inspection . . . . . . . . . . . . . . . . . . . 258

1205.1 Operating Instructions . . . . . . . . . 258

1205.2 Pressure Testing . . . . . . . . . . . . . 258

1205.3 Flushing . . . . . . . . . . . . . . . . . . . . 259

1206.0 Pressure and Safety Devices . . . . 259

1206.1 General. . . . . . . . . . . . . . . . . . . . . 259

1206.2 Discharge Piping . . . . . . . . . . . . . 259

1207.0 Heating Appliances and Equipment . . . . . . . . . . . . . . . . . . 259

1207.1 General. . . . . . . . . . . . . . . . . . . . . 259

1207.2 Boilers. . . . . . . . . . . . . . . . . . . . . . 259

1207.3 Dual Purpose Water Heaters . . . . 259

1207.4 Solar Heat Collector Systems. . . . 259

1207.5 Heat Pumps . . . . . . . . . . . . . . . . . 259

1208.0 Circulators and Pumps . . . . . . . . . 259

1208.1 General. . . . . . . . . . . . . . . . . . . . . 259

1208.2 Mounting. . . . . . . . . . . . . . . . . . . . 260

1208.3 Sizing . . . . . . . . . . . . . . . . . . . . . . 260

1209.0 Expansion Tanks . . . . . . . . . . . . . 260

1209.1 General. . . . . . . . . . . . . . . . . . . . . 260

1209.2 Installation . . . . . . . . . . . . . . . . . . 260

1209.3 Closed-Type Tanks . . . . . . . . . . . 260

1209.4 Sizing . . . . . . . . . . . . . . . . . . . . . . 260

1210.0 Materials . . . . . . . . . . . . . . . . . . . . 260

1210.1 Piping, Tubing, and Fittings . . . . . 260

1210.2 Expansion and Contraction . . . . . . 260

1210.3 Hangers and Supports . . . . . . . . . 260

1210.4 Oxygen Diffusion Corrosion . . . . . 260

1211.0 Joints and Connections . . . . . . . . 260

1211.1 General. . . . . . . . . . . . . . . . . . . . . 260

1211.2 Pipe Bends . . . . . . . . . . . . . . . . . . 260

Table 1210.1 Materials for Hydronic System Piping, Tubing, and Fittings . . . . . 261

Table 1211.2.2 Minimum Bend Radius

for PE Pipe Installed in Open Cut Trench . . . . . . . . . . . . . 262

1211.3 Chlorinated Polyvinyl Chloride (CPVC) Pipe . . . . . . . . . . . . . . . . . 262

1211.4 CPVC/AL/CPVC Plastic Pipe and Joints . . . . . . . . . . . . . . . . . . . 262

1211.5 Copper or Copper Alloy Pipe and Tubing . . . . . . . . . . . . . . . . . . 262

1211.6 Crossed-Linked Polyethylene (PEX) Pipe . . . . . . . . . . . . . . . . . . 263

1211.7 Cross-Linked Polyethylene/ Aluminum/Cross-Linked

Polyethylene (PEX-AL-PEX) Pipe. . 263

1211.8 Ductile Iron Pipe . . . . . . . . . . . . . . 263

1211.9 Polyethylene (PE) Plastic Pipe/Tubing. . . . . . . . . . . . 263

1211.10 Polyethylene/Aluminum/ Polyethylene (PE-AL-PE) . . . . . . . 264

1211.11 Polyethylene of Raised Temperature (PE-RT). . . . . . . . . . 264

1211.12 Polypropylene (PP) Pipe. . . . . . . . 264

1211.13 Polyvinyl Chloride (PVC) Pipe . . . 264

1211.14 Steel Pipe and Tubing . . . . . . . . . 265

1211.15 Stainless Steel Pipe and Joints. . . 265

1211.16 Joints Between Various Materials. . 265

1212.0 Valves. . . . . . . . . . . . . . . . . . . . . . 265

1212.1 General. . . . . . . . . . . . . . . . . . . . . 265

1212.2 Where Required . . . . . . . . . . . . . . 265

1212.3 Heat Exchanger . . . . . . . . . . . . . . 265

1212.4 Pressure Vessels . . . . . . . . . . . . . 265

1212.5 Pressure Reducing Valves . . . . . . 265

1212.6 Equipment, Components, and Appliances . . . . . . . . . . . . . . . . . . 265

1212.7 Expansion Tank . . . . . . . . . . . . . . 265

1212.8 Flow Balancing Valves . . . . . . . . . 265

1212.9 Mixing or Temperature Control Valves. . . . . . . . . . . . . . . . . . . . . . 265

1212.10 Thermosiphoning . . . . . . . . . . . . . 265

1212.11 Air Removal Device or Air Vents . . 265

1212.12 District Energy and Central Utility Systems. . . . . . . . . . . . . . . . 265

1213.0 System Controls . . . . . . . . . . . . . . 265

1213.1 Water Temperature Controls . . . . 265

1213.2 Operating Steam Controls . . . . . . 266

1213.3 Occupied Spaces . . . . . . . . . . . . . 266

1213.4 Simultaneous Operation . . . . . . . . 266

1213.5 Temperature Reading. . . . . . . . . . 266

1214.0 Pressure and Flow Controls . . . . . 266

1214.1 Balancing . . . . . . . . . . . . . . . . . . . 266

1214.2 Low-Water Control . . . . . . . . . . . . 266

1214.3 Flow-Sensing Devices . . . . . . . . . 266

1214.4 Automatic Makeup Fluid . . . . . . . . 266

1214.5 Differential Pressure Regulation. . . 266

1214.6 Air-Removal Device . . . . . . . . . . . 266

1214.7 Air-Separation Device. . . . . . . . . . 266

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

TABLE OF CONTENTS

1214.8 Secondary Loops . . . . . . . . . . . . . 266

1215.0 Hydronic Space Heating. . . . . . . . 266

1215.1 General. . . . . . . . . . . . . . . . . . . . . 266

1215.2 Installation . . . . . . . . . . . . . . . . . . 266

1215.3 Balancing . . . . . . . . . . . . . . . . . . . 267

1215.4 Heat Transfer Fluid. . . . . . . . . . . . 267

1216.0 Steam Systems. . . . . . . . . . . . . . . 267

1216.1 Steam Traps . . . . . . . . . . . . . . . . . 267

1216.2 Sloping for Two-Pipe System . . . . 267

1216.3 Sloping for One-Pipe System . . . . 267

1216.4 Automatic Air Vents . . . . . . . . . . . 267

1216.5 Condensate Flow . . . . . . . . . . . . . 267

1216.6 Steam-Distribution Piping . . . . . . . 267

1217.0 Radiant Heating and Cooling . . . . 267

1217.1 Installation . . . . . . . . . . . . . . . . . . 267

1217.2 Radiant Under-Floor Heating . . . . 267

1217.3 Radiant Cooling Systems . . . . . . . 267

1217.4 Chilled Water

Supply/Distribution Piping . . . . . . . 267

1217.5 Tube Placement . . . . . . . . . . . . . . 267

1217.6 Tube Length . . . . . . . . . . . . . . . . . 267

Table 1217.6 Maximum Length of Continuous Tubing from a Supply-and-Return Manifold Arrangement . . . . . . . . . 267

1217.7 Tube Identification . . . . . . . . . . . . 267

1217.8 Poured Floor Structural Concrete

Slab Systems (Thermal Mass) . . . 268

1217.9 Joist Systems and Subfloors . . . . 268

1217.10 Wall and Ceiling Panels . . . . . . . . 268

1217.11 Radiant Heating and Cooling

Panels. . . . . . . . . . . . . . . . . . . . . . 268

1218.0 Heat Exchangers . . . . . . . . . . . . . 269

1218.1 General. . . . . . . . . . . . . . . . . . . . . 269

1219.0 Indirect-Fired Domestic

Hot-Water Storage Tanks. . . . . . . 269

1219.1 General. . . . . . . . . . . . . . . . . . . . . 269

1220.0 Snow and Ice Melt Systems . . . . . 269

1220.1 Use of Chemical Additives

and Corrosive Fluids. . . . . . . . . . . 269

1220.2 Types of Tube Fasteners . . . . . . . 269

1220.3 Spacing of Tube Fasteners . . . . . 269

1220.4 Snow and Ice Melt Controls . . . . . 269

Table 1220.4.2 Maximum Loop Lengths for Snow and Ice Melt Systems . . . . . 270

1220.5 Hydronic Makeup Air Units . . . . . . 270

1221.0 Piping Installation . . . . . . . . . . . . . 270

1221.1 General. . . . . . . . . . . . . . . . . . . . . 270

1221.2 Embedded Piping Materials and Joints . . . . . . . . . . . . . . . . . . . 270

1221.3 Pressure Testing . . . . . . . . . . . . . 270

1221.4 System Drainage . . . . . . . . . . . . . 270

1221.5 Condensate Drainage. . . . . . . . . . 271

1221.6 Hydronic Fluid Disposal . . . . . . . . 271

1221.7 Clearance to Combustibles . . . . . 271

CHAPTER 13 FUEL GAS PIPING . . . . . . . . . . . 273

1301.0 Scope of Gas Piping . . . . . . . . . . 275

1301.1 Applicability. . . . . . . . . . . . . . . . . . 275

1302.0 Coverage of Piping System . . . . . 275

1302.1 General. . . . . . . . . . . . . . . . . . . . . 275

1302.2 Piping System Requirements . . . . 275

1302.3 Applications . . . . . . . . . . . . . . . . . 275

1303.0 Inspection . . . . . . . . . . . . . . . . . . . 275

1303.1 Inspection Notification . . . . . . . . . 275

1303.2 Excavation . . . . . . . . . . . . . . . . . . 275

1303.3 Type of Inspections . . . . . . . . . . . 275

1303.4 Inspection Waived . . . . . . . . . . . . 276

1304.0 Certificate of Inspection . . . . . . . . 276

1304.1 Issuance . . . . . . . . . . . . . . . . . . . . 276

1304.2 Gas Supplier. . . . . . . . . . . . . . . . . 276

1304.3 Unlawful . . . . . . . . . . . . . . . . . . . . 276

1305.0 Authority to Render Gas Service . . 276

1305.1 Authorized Personnel . . . . . . . . . . 276

1305.2 Outlets . . . . . . . . . . . . . . . . . . . . . 276

1306.0 Authority to Disconnect. . . . . . . . . 276

1306.1 Disconnection . . . . . . . . . . . . . . . . 276

1306.2 Notice . . . . . . . . . . . . . . . . . . . . . . 276

1306.3 Capped Outlets. . . . . . . . . . . . . . . 276

1307.0 Temporary Use of Gas . . . . . . . . . 276

1307.1 General. . . . . . . . . . . . . . . . . . . . . 276

1308.0 Gas Piping System Design, Materials, and Components . . . . . 276

1308.1 Installation of Piping System . . . . 276

1308.2 Interconnections Supplying Separate Users. . . . . . . . . . . . . . . 276

1308.3 Sizing of Gas Piping Systems . . . 277

1308.4 Acceptable Piping Materials and Joining Methods . . . . . . . . . . 277

Table 1308.3.1 Approximate Gas Input for Typical Appliances . . . . . . . . . . . . 277

Table 1308.4.6.2 Specifications for Threading Metallic Pipe . . . . . . . . . . . . . . . . . 278

1308.5 Gas Meters . . . . . . . . . . . . . . . . . . 280

1308.6 Gas Pressure Regulators . . . . . . . 280

1308.7 Overpressure Protection. . . . . . . . 281

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

TABLE OF CONTENTS

1308.8 Pressure Limitation

Requirements . . . . . . . . . . . . . . . . 281

1308.9 Overpressure Protection Devices. . . . . . . . . . . . . . . . . . . . . 281

1308.10 Backpressure Protection . . . . . . . 282

1308.11 Low-Pressure Protection . . . . . . . 282

1308.12 Shutoff Valves . . . . . . . . . . . . . . . 282

Table 1308.12 Manual Gas Valve Standards. . . . 282

1308.13 Expansion and Flexibility . . . . . . . 282

1308.14 Pressure Regulator and Pressure Control Venting . . . . . . . 282

1309.0 Excess Flow Valve . . . . . . . . . . . . 283

1309.1 General. . . . . . . . . . . . . . . . . . . . . 283

1310.0 Gas Piping Installation . . . . . . . . . 283

1310.1 Piping Underground . . . . . . . . . . . 283

1310.2 CSST Piping Systems . . . . . . . . . 284

1310.3 Installation of Aboveground Piping . . . . . . . . . . . . . . . . . . . . . . 284

Table 1310.3.5.1 Support of Piping . . . . . . . . . . . . . 285

1310.4 Concealed Piping in Buildings . . . 285

1310.5 Piping in Vertical Chases . . . . . . . 286

1310.6 Maximum Operating Pressure in Buildings . . . . . . . . . . . . . . . . . . 286

1310.7 Appliance Overpressure Protection . . . . . . . . . . . . . . . . . . . 286

1310.8 Gas Pipe Turns. . . . . . . . . . . . . . . 286

1310.9 Drips and Sediment Traps . . . . . . 287

1310.10 Outlets . . . . . . . . . . . . . . . . . . . . . 287

1310.11 Manual Gas Shutoff Valves . . . . . 287

1310.12 Prohibited Devices . . . . . . . . . . . . 288

1310.13 Systems Containing Gas-Air Mixtures Outside the Flammable

Range . . . . . . . . . . . . . . . . . . . . . . 288

1310.14 Systems Containing Flammable Gas-Air Mixtures. . . . . . . . . . . . . . 288

1311.0 Electrical Bonding and Grounding. . . . . . . . . . . . . . . . . . . 289

1311.1 Pipe and Tubing other than CSST . . . . . . . . . . . . . . . . . . . . . . 289

1311.2 Bonding of CSST Gas Piping . . . . 289

1311.3 Arc-Resistant Jacketed CSST . . . 289

1311.4 Prohibited Use . . . . . . . . . . . . . . . 289

1311.5 Lightning Protection System. . . . . 289

1311.6 Electrical Circuits . . . . . . . . . . . . . 289

1311.7 Electrical Connections . . . . . . . . . 289

1312.0 Appliance and Equipment Connections to Building Piping. . . 289

1312.1 Connecting Appliances and Equipment . . . . . . . . . . . . . . . . . . 289

1312.2 Suspended Low-Intensity Infrared Tube Heaters . . . . . . . . . 290

1312.3 Use of Nonmetallic Gas Hose

Connectors . . . . . . . . . . . . . . . . . . 290

1312.4 Injection (Bunsen) Burners . . . . . . 290

1312.5 Connection of Portable and

Mobile Industrial Appliances. . . . . 290

1312.6 Appliance Shutoff Valves and Connections. . . . . . . . . . . . . . 291

1312.7 Quick-Disconnect Devices . . . . . . 291

1312.8 Gas Convenience Outlets. . . . . . . 291

1312.9 Sediment Trap . . . . . . . . . . . . . . . 291

1312.10 Installation of Piping . . . . . . . . . . . 291

1312.11 Liquefied Petroleum Gas Facilities and Piping . . . . . . . . . . . 291

1313.0 Pressure Testing, Inspection, and Purging. . . . . . . . . . . . . . . . . . 291

1313.1 Piping Installations . . . . . . . . . . . . 291

1313.2 Test Preparation . . . . . . . . . . . . . . 292

1313.3 Test Pressure . . . . . . . . . . . . . . . . 292

1313.4 Detection of Leaks and Defects . . 292

1313.5 Piping System Leak Test . . . . . . . 292

1313.6 Purging Requirements . . . . . . . . . 292

Table 1313.6.1 Size and Length of Piping. . . . . . . 293

1314.0 Required Gas Supply . . . . . . . . . . 293

1314.1 General. . . . . . . . . . . . . . . . . . . . . 293

1314.2 Volume . . . . . . . . . . . . . . . . . . . . . 293

1314.3 Gas Appliances . . . . . . . . . . . . . . 294

1314.4 Size of Piping Outlets . . . . . . . . . . 294

1315.0 Required Gas Piping Size . . . . . . 294

1315.1 Pipe Sizing Methods. . . . . . . . . . . 294

1315.2 Sizing of Gas Piping Systems . . . 294

1315.3 Sizing Equations. . . . . . . . . . . . . . 294

Table 1315.3 Cr and Y for Natural Gas and

Undiluted Propane at Standard Conditions. . . . . . . . . . . . . . . . . . . 295

1315.4 Sizing of Piping Sections . . . . . . . 295

1315.5 Engineering Methods . . . . . . . . . . 295

1315.6 Variable Gas Pressures . . . . . . . . 295

Table 1315.2(1) Schedule 40 Metallic Pipe . . . . . . 297

Table 1315.2(2) Schedule 40 Metallic Pipe . . . . . . 298

Table 1315.2(3) Schedule 40 Metallic Pipe . . . . . . 299

Table 1315.2(4) Schedule 40 Metallic Pipe . . . . . . 300

Table 1315.2(5) Schedule 40 Metallic Pipe . . . . . . 301

Table 1315.2(6) Schedule 40 Metallic Pipe . . . . . . 302

Table 1315.2(7) Semi-Rigid Copper Tubing . . . . . . 303

Table 1315.2(8) Semi-Rigid Copper Tubing . . . . . . 304

Table 1315.2(9) Semi-Rigid Copper Tubing . . . . . . 305

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

TABLE OF CONTENTS

Table 1315.2(10) Semi-Rigid Copper Tubing . . . . . . 306

Table 1315.2(11) Semi-Rigid Copper Tubing . . . . . . 307

Table 1315.2(12) Semi-Rigid Copper Tubing . . . . . . 308

Table 1315.2(13) Semi-Rigid Copper Tubing . . . . . . 309

Table 1315.2(14) Corrugated Stainless Steel Tubing (CSST) . . . . . . . . . . . . . . . 310

Table 1315.2(15) Corrugated Stainless Steel Tubing (CSST) . . . . . . . . . . . . . . . 311

Table 1315.2(16) Corrugated Stainless Steel Tubing (CSST) . . . . . . . . . . . . . . . 312

Table 1315.2(17) Corrugated Stainless Steel Tubing (CSST) . . . . . . . . . . . . . . . 313

Table 1315.2(18) Corrugated Stainless Steel Tubing (CSST) . . . . . . . . . . . . . . . 314

Table 1315.2(19) Polyethylene Plastic Pipe . . . . . . . 315

Table 1315.2(20) Polyethylene Plastic Pipe . . . . . . . 216

Table 1315.2(21) Polyethylene Plastic Pipe . . . . . . . 317

Table 1315.2(22) Polyethylene Plastic Tubing . . . . . 318

Table 1315.2(23) Polyethylene Plastic Tubing . . . . . 318

Table 1315.2(24) Schedule 40 Metallic Pipe . . . . . . 319

Table 1315.2(25) Schedule 40 Metallic Pipe . . . . . . 320

Table 1315.2(26) Schedule 40 Metallic Pipe . . . . . . 321

Table 1315.2(27) Schedule 40 Metallic Pipe . . . . . . 322

Table 1315.2(28) Semi-Rigid Copper Tubing . . . . . . 323

Table 1315.2(29) Semi-Rigid Copper Tubing . . . . . . 324

Table 1315.2(30) Semi-Rigid Copper Tubing . . . . . . 330

Table 1315.2(31) Corrugated Stainless Steel Tubing (CSST) . . . . . . . . . . . . . . . 326

Table 1315.2(32) Corrugated Stainless Steel Tubing (CSST) . . . . . . . . . . . . . . . 327

Table 1315.2(33) Corrugated Stainless Steel Tubing (CSST) . . . . . . . . . . . . . . . 328

Table 1315.2(34) Polyethylene Plastic Pipe . . . . . . . 329

Table 1315.2(35) Polyethylene Plastic Pipe . . . . . . . 330

Table 1315.2(36) Polyethylene Plastic Tubing . . . . . 331

CHAPTER 14 PROCESS PIPING. . . . . . . . . . . . 333

1401.0 General. . . . . . . . . . . . . . . . . . . . . 335

1401.1 Applicability. . . . . . . . . . . . . . . . . . 335

1402.0 Permit . . . . . . . . . . . . . . . . . . . . . . 335

1402.1 General. . . . . . . . . . . . . . . . . . . . . 335

1403.0 Plans Required . . . . . . . . . . . . . . . 335

1403.1 General. . . . . . . . . . . . . . . . . . . . . 335

1404.0 Workmanship . . . . . . . . . . . . . . . . 335

1404.1 General. . . . . . . . . . . . . . . . . . . . . 335

1405.0 Inspections . . . . . . . . . . . . . . . . . . 335

1405.1 General. . . . . . . . . . . . . . . . . . . . . 335

1405.2 Required Inspections . . . . . . . . . . 335

1405.3 Other Inspections . . . . . . . . . . . . . 335

1406.0 Pipe, Tubing, and Fittings. . . . . . . 335

1406.1 General. . . . . . . . . . . . . . . . . . . . . 335

1406.2 Hazardous Process

Piping (HPP). . . . . . . . . . . . . . . . . 335

1406.3 Special Requirements for HPP Gases . . . . . . . . . . . . . . . . . . . . . . 336

CHAPTER 15 SOLAR ENERGY SYSTEMS. . . . 337

1501.0 General. . . . . . . . . . . . . . . . . . . . . 339

1501.1 Applicability. . . . . . . . . . . . . . . . . . 339

CHAPTER 16 STATIONARY POWER

PLANTS . . . . . . . . . . . . . . . . . . . . 341

1601.0 Stationary Fuel Cell Power Plants . . . . . . . . . . . . . . . . . . . . . . 343

1601.1 General. . . . . . . . . . . . . . . . . . . . . 343

1602.0 Stationary Gas Engines and Generators and Gas Turbines . . . 343

1602.1 Gas Engines . . . . . . . . . . . . . . . . . 343

Gas Turbines . . . . . . . . . . . . . . . . 343

1602.3 Stationary Engine Generators . . . 343

CHAPTER 17 GEOTHERMAL ENERGY

SYSTEMS AND AMBIENT

TEMPERATURE LOOPS. . . . . . . 345

Part I General . . . . . . . . . . . . . . . . . . . . 347

1701.0 General. . . . . . . . . . . . . . . . . . . . . 347

1701.1 Applicability. . . . . . . . . . . . . . . . . . 347

1701.2 Construction Documents . . . . . . . 347

1701.3 Site Survey . . . . . . . . . . . . . . . . . . 347

1701.4 Used Materials . . . . . . . . . . . . . . . 347

1701.5 Contact with Building Material . . . 347

1701.6 Strains and Stresses . . . . . . . . . . 347

1701.7 Flood Hazard . . . . . . . . . . . . . . . . 347

1701.8 Pipe Support. . . . . . . . . . . . . . . . . 347

1701.9 Velocities . . . . . . . . . . . . . . . . . . . 347

1701.10 Chemical Compatibility . . . . . . . . . 347

1701.11 Heat Transfer Fluid. . . . . . . . . . . . 347

1702.0 Groundwater Systems . . . . . . . . . 347

1702.1 General. . . . . . . . . . . . . . . . . . . . . 347

Table 1701.11.1 Water Quality . . . . . . . . . . . . . . . . 348

1703.0 Design of Systems . . . . . . . . . . . . 348

1703.1 Ground-Heat Exchanger Design . . . . . . . . . . . . . . . . . . . . . 348

1703.2 Piping and Tubing Materials Standards . . . . . . . . . . . . . . . . . . . 348

xliv 2025 CALIFORNIA MECHANICAL CODE

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

TABLE OF CONTENTS

Table 1703.2 Plastic Ground Source

Loop Piping. . . . . . . . . . . . . . . . . . 348

1703.3 Fittings . . . . . . . . . . . . . . . . . . . . . 348

Table 1703.3 Ground Source Loop Pipe Fittings . . . . . . . . . . . . . . . . . 348

1703.4 Underground Piping and Submerged Materials . . . . . . . . . . 348

1703.5 Indoor Piping . . . . . . . . . . . . . . . . 349

1704.0 Heat Pumps . . . . . . . . . . . . . . . . . 349

1704.1 Heat Pump Distribution System . . . . . . . . . . . . . . . . . . . . . 349

1704.2 Circulating Pumps . . . . . . . . . . . . 349

1705.0 Valves. . . . . . . . . . . . . . . . . . . . . . 349

1705.1 Where Required . . . . . . . . . . . . . . 349

1705.2 Heat Exchangers . . . . . . . . . . . . . 349

1705.3 Central Systems . . . . . . . . . . . . . . 349

1705.4 Pressure Vessels . . . . . . . . . . . . . 349

1705.5 Pressure-Reducing Valves . . . . . . 349

1705.6 Equipment and Appliances. . . . . . 349

1705.7 Expansion Tanks . . . . . . . . . . . . . 349

1705.8 Reduced Pressure . . . . . . . . . . . . 350

1706.0 Specific System Components Design . . . . . . . . . . . . . . . . . . . . . 350

1706.1 General. . . . . . . . . . . . . . . . . . . . . 350

Table 1706.1 Heat Pumps . . . . . . . . . . . . . . . . . 350

1706.2 Heat Exchangers . . . . . . . . . . . . . 350

1706.3 Heat-Transfer Medium . . . . . . . . . 350

1706.4 Insulation . . . . . . . . . . . . . . . . . . . 350

1707.0 Installation Practices. . . . . . . . . . . 350

1707.1 Prior to Construction. . . . . . . . . . . 350

1707.2 Equipment, Accessories, Components, and Materials . . . . . 350

1707.3 Construction Documents . . . . . . . 350

1707.4 Site Survey Requirements . . . . . . 350

1707.5 Subsurface Investigation . . . . . . . 350

1707.6 Subsurface Conditions . . . . . . . . . 350

1707.7 Ground-Heat Exchanger Installation Practices. . . . . . . . . . . 350

1707.8 Trenching, Excavation, and Backfill . . . . . . . . . . . . . . . . . . 351

1707.9 Trenches, Tunneling, and Driving . . . . . . . . . . . . . . . . . . 351

1707.10 Excavations and

Open Trenches. . . . . . . . . . . . . . . 351

1707.11 Protection of Piping, Materials, and Structures . . . . . . . 351

1707.12 Sleeves. . . . . . . . . . . . . . . . . . . . . 351

1707.13 Steel Nail Plates . . . . . . . . . . . . . . 351

1707.14 Exterior Piping Protection . . . . . . . 351

1707.15 Heat Pump and Distribution System Installation . . . . . . . . . . . . 351

1707.16 Pressurizing During Installation . . . . . . . . . . . . . . . . . . 351

1707.17 Horizontal Geothermal

Piping - Materials and Methods . . 351

1707.18 Trenches, Excavation,

and Backfill . . . . . . . . . . . . . . . . . . 351

1708.0 System Start-Up . . . . . . . . . . . . . . 352

1708.1 General. . . . . . . . . . . . . . . . . . . . . 352

1708.2 Operation and Maintenance Manual . . . . . . . . . . . . . . . . . . . . . 352

1708.3 Labeling and Marking . . . . . . . . . . 352

1708.4 Documentation . . . . . . . . . . . . . . . 352

1708.5 Maintenance . . . . . . . . . . . . . . . . . 352

1708.6 Records . . . . . . . . . . . . . . . . . . . . 352

1708.7 System Start-Up . . . . . . . . . . . . . . 352

1708.8 Contaminants . . . . . . . . . . . . . . . . 352

1709.0 Decommissioning and Abandonment . . . . . . . . . . . . . . . . 352

1709.1 General. . . . . . . . . . . . . . . . . . . . . 352

Part II Closed-Loop Systems . . . . . . . . 352

1710.0 General. . . . . . . . . . . . . . . . . . . . . 352

1710.1 Applicability. . . . . . . . . . . . . . . . . . 352

1710.2 Piping and Tubing. . . . . . . . . . . . . 352

1710.3 Borehole Piping and Tubing . . . . . 352

1710.4 Underground Fittings . . . . . . . . . . 352

1710.5 Verification . . . . . . . . . . . . . . . . . . 353

1710.6 Vertical Bores . . . . . . . . . . . . . . . . 353

1711.0 Ground-Heat Exchanger Testing . . . . . . . . . . . . . . . . . . . . . 353

1711.1 Testing . . . . . . . . . . . . . . . . . . . . . 353

1711.2 Individual Loop Pressure Testing . . . . . . . . . . . . . . . . . . . . . 353

1711.3 Field Pressure Testing – Final . . . 353

1711.4 Field Flow Testing – Final. . . . . . . 353

Part III Open-Loop Systems . . . . . . . . . . 353

1712.0 General. . . . . . . . . . . . . . . . . . . . . 353

1712.1 Applicability. . . . . . . . . . . . . . . . . . 353

1712.2 Test Wells. . . . . . . . . . . . . . . . . . . 353

1712.3 Installation of Water Wells . . . . . . 354

1712.4 Setbacks. . . . . . . . . . . . . . . . . . . . 354

1713.0 Open Ground Water Systems . . . 354

1713.1 General. . . . . . . . . . . . . . . . . . . . . 354

1713.2 Open-Loop Water Well Drilling Logs . . . . . . . . . . . . . . . . . 354

1713.3 Design Considerations . . . . . . . . . 354

1713.4 Water Wells and Injection Wells. . . 354

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

TABLE OF CONTENTS

1713.5 Testing and Sampling. . . . . . . . . . 354

1713.6 Disinfection . . . . . . . . . . . . . . . . . . 354

1714.0 Testing and Verification . . . . . . . . 354

1714.1 Pumping Test . . . . . . . . . . . . . . . . 354

1714.2 Retesting . . . . . . . . . . . . . . . . . . . 354

1714.3 Variable Rate Pump Test . . . . . . . 355

1714.4 Constant Rate Pump Test . . . . . . 355

1714.5 Water Level Monitoring. . . . . . . . . 355

1714.6 Injection Wells . . . . . . . . . . . . . . . 355

1714.7 Re-Injected Water. . . . . . . . . . . . . 355

Part IV Direct Exchange (DX) Systems . . . . . . . . . . . . . . . . . . . . 355

1715.0 Direct Exchange (DX) Systems . . . . . . . . . . . . . . . . . . . . 355

1715.1 General. . . . . . . . . . . . . . . . . . . . . 355

1715.2 Applicability. . . . . . . . . . . . . . . . . . 355

1715.3 DX Systems . . . . . . . . . . . . . . . . . 355

1715.4 DX System Testing. . . . . . . . . . . . 355

1715.5 Indoor Piping . . . . . . . . . . . . . . . . 355

1715.6 On Site Storage . . . . . . . . . . . . . . 355

1715.7 System Start-Up . . . . . . . . . . . . . . 355

1715.8 DX Piping . . . . . . . . . . . . . . . . . . . 355

Part V Geothermal Ambient

Temperature Loops (ATL) . . . . . 355

1716.0 Ambient Temperature Loop (ATL) Distributed Energy Systems . . . . . . . . . . . . . . 355

1716.1 General. . . . . . . . . . . . . . . . . . . . . 355

1716.2 Permitting . . . . . . . . . . . . . . . . . . . 356

1716.3 Ambient Loop Temperature Range . . . . . . . . . . . . . . . . . . . . . . 356

1716.4 Shutoff Valve . . . . . . . . . . . . . . . . 356

1716.5 Bypass . . . . . . . . . . . . . . . . . . . . . 356

1716.6 Metering . . . . . . . . . . . . . . . . . . . . 356

1717.0 ATL Distributed Energy Systems Design Requirements . . 356

1717.1 Thermal Resources . . . . . . . . . . . 356

1717.2 District Load Profiles. . . . . . . . . . . 357

CHAPTER 18 REFERENCED STANDARDS . . . 359

1801.0 General. . . . . . . . . . . . . . . . . . . . . 361

1801.1 Standards . . . . . . . . . . . . . . . . . . . 361

Table 1801.1 Referenced Standards . . . . . . . . . 361

1801.2 Standards, Publications Practices, and Guides . . . . . . . . . 378

Table 1801.2 Standards, Publications Practices, and Guides . . . . . . . . . 378

APPENDICES TABLE OF CONTENTS. . . . . . . . 385

Appendix A Residential Plans Examiner Review Form for HVAC

System Design . . . . . . . . . . . . . . . 387

Appendix B Procedures to be Followed to Place Gas Equipment in Operation . . . . . . . . . . . . . . . . . . . 391

Appendix C Installation and Testing of Oil (Liquid) Fuel-Fired Equipment . . . 395

Appendix D Fuel Supply: Manufactured/Mobile Home Parks and Recreational

Vehicle Parks . . . . . . . . . . . . . . . . 403

Appendix E Sustainable Practices . . . . . . . . . . 411

Appendix F Sizing of Venting Systems and Outdoor Combustion and

Ventilation Opening Design . . . . . 533

Appendix G Example Calculation of Outdoor Air Rate. . . . . . . . . . . . . . 545

Appendix H Professional Qualifications . . . . . . 549

Appendix I Indoor Horticultural Facilities . . . . 553

Appendix J Clean Air Delivery. . . . . . . . . . . . . 559

USEFUL TABLES . . . . . . . . . . . . . . . . . . . . . . . . . . . 563

INDEX . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 571

HISTORY NOTE

APPENDIX . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 593

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CHAPTER 1 – ADMINISTRATION

(Matrix Adoption Tables are non-regulatory, intended only as an aid to the code user. See Chapter 1 for state agency authority and building applications.)

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CHAPTER 1 – ADMINISTRATION (continued) (Matrix Adoption Tables are non-regulatory, intended only as an aid to the code user. See Chapter 1 for state agency authority and building applications.)

This state agency does not adopt sections identified with the following symbol: The Office of the State Fire Marshal’s adoption of this chapter or individual sections is applicable to structures regulated by other state agencies pursuant to Section 1.11.0.

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CHAPTER 1

ADMINISTRATION

DIVISION I CALIFORNIA ADMINISTRATION

1.1.0 General.

1.1.1 Title. These regulations shall be known as the California Mechanical Code, may be cited as such and will be referred to herein as “this code.” The California Mechanical Code is Part 4 of thirteen parts of the official compilation and publi- cation of the adoption, amendment, and repeal of mechanical regulations to the California Code of Regulations, Title 24, also referred to as the California Building Standards Code. This part incorporates by adoption the 2024 Uniform Mechan- ical Code of the International Association of Plumbing and Mechanical Officials with necessary California amendments.

1.1.2 Purpose. The purpose of this code is to establish the minimum requirements to safeguard the public health, safety and general welfare through structural strength, means of egress facilities, stability, access to persons with disabilities, sanitation, adequate lighting and ventilation, and energy conservation; safety to life and property from fire and other hazards attributed to the built environment; and to provide safety to fire fighters and emergency responders during emer- gency operations.

1.1.3 Scope. The provisions of this code shall apply to the construction, alteration, movement, enlargement, replace- ment, repair, equipment, use and occupancy, location, main- tenance, removal, and demolition of every building or structure or any appurtenances connected or attached to such buildings or structures throughout the State of California.

1.1.3.1 Nonstate-Regulated Buildings, Structures, and Applications. Except as modified by local ordinance pursuant to Section 1.1.8, the following standards in the California Code of Regulations, Title 24, Parts 2, 2.5, 3, 4, 5, 6, 7, 9, 10 and 11 shall apply to all occupancies and applications not regulated by a state agency.

1.1.3.2 State-Regulated Buildings, Structures, and Applications. The model code, state amendments to the model code, and/or state amendments where there are no relevant model code provisions shall apply to the following buildings, structures, and applications regu- lated by state agencies as specified in Sections 1.2.0 through 1.14.0, except where modified by local ordinance pursuant to Section 1.1.8. When adopted by a state agency, the provisions of this code shall be enforced by the appropriate enforcing agency, but only to the extent of authority granted to such agency by the state legislature.

Note: See “How to Distinguish Between Model Code Language and California Amendments” in the front of the code.

(1) State-owned buildings, including buildings constructed by the Trustees of the California State University, and to the extent permitted by California laws, buildings designed and constructed by the

Regents of the University of California, and regu- lated by the Building Standards Commission. See Section 1.2.0 for additional scope provisions.

(2) Section 1.3.0 is reserved for the Board of State and Community Corrections.

(3) Section 1.4.0 is reserved for the Department of Consumer Affairs.

(4) Section 1.5.0 is reserved for the California Energy Commission.

(5) Section 1.6.0 is reserved for the Department of Food and Agriculture.

(6) Organized camps, laboratory animal quarters, public swimming pools, radiation protection, commissaries serving mobile food preparation vehi- cles, and wild animal quarantine facilities regulated by the Department of Public Health. See Section 1.7.0 for additional scope provisions.

(7) Hotels, motels, lodging houses, apartments, dwellings, dormitories, condominiums, shelters for homeless persons, congregate residences, employee housing, factory-built housing and other types of dwellings containing sleeping accommodations with or without common toilets or cooking facilities. See Section 1.8.2.1.1 for additional scope provisions.

(8) Accommodations for persons with disabilities in buildings containing newly constructed covered multifamily dwellings, new common use areas serving existing covered multifamily dwellings, additions to existing buildings where the addition alone meets the definition of covered multifamily dwellings and new common-use areas serving new covered multifamily dwellings which are regulated by the Department of Housing and Community Development. See Section 1.8.2.1.2 for additional scope provisions.

(9) Permanent buildings and permanent accessory build- ings or structures constructed within mobilehome parks and special occupancy parks regulated by the Department of Housing and Community Development. See Section 1.8.2.1.3 for additional scope provisions.

(10)Accommodations for persons with disabilities regu- lated by the Division of the State Architect. See Section 1.9.1 for additional scope provisions.

(11) Public elementary and secondary schools, commu- nity college buildings and state-owned or state- leased essential service buildings regulated by the Division of the State Architect. See Section 1.9.2 for additional scope provisions.

(12)Reserved for the State Historical Building Safety Board with the Division of the State Architect.

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(13)General acute care hospitals, acute psychiatric hospitals, skilled nursing and/or intermediate care facilities, clinics licensed by the Department of Public Health and correctional treatment centers regulated by the Department of Health Care Access and Information/Office of Statewide Hospital Plan- ning and Development. See Section 1.10.0 for addi- tional scope provisions.

(14)Applications regulated by the Office of State Fire Marshal include but are not limited to the following in accordance with Section 1.11.0:

(1) Buildings or structures used or intended for use

as an:

1.1. Asylum, jail, prison.

1.2. Mental hospital, hospital, home for the elderly, children’s nursery, children’s home or institution, school or any similar occu- pancy of any capacity.

1.3. Theater, dancehall, skating rink, audito- rium, assembly hall, meeting hall, night- club, fair building or similar place of assemblage where 50 or more persons may gather together in a building, room, or structure for the purpose of amusement, entertainment, instruction, deliberation, worship, drinking or dining, awaiting transportation, or education.

1.4. Small family day care homes, large family day-care homes, residential facilities and residential facilities for the elderly, resi- dential care facilities.

1.5. State institutions or other state-owned or state-occupied buildings.

1.6. High rise structures.

1.7. Motion picture production studios.

1.8. Organized camps.

1.9. Residential structures.

(2) Tents, awnings, or other fabric enclosures used in connection with any occupancy.

(3) Fire alarm devices, equipment, and systems in connection with any occupancy.

(4) Hazardous materials, flammable, and combustible liquids.

(5) Public school automatic fire detection, alarm, and sprinkler systems.

(6) Wildland-urban interface fire areas.

(15)Section 1.12.0 is reserved for public libraries constructed and renovated using funds from the California Library Construction and Renovation Bond Act of 1988 and regulated by the State Librarian.

(16)Section 1.13.0 is reserved for the Department of Water Resources.

(17)For applications listed in Section 1.9.1 regulated by the Division of the State Architect – Access Compli-

ance, outdoor environments and uses shall be clas- sified according to accessibility uses described in Chapters 11A and 11B.

(18)Section 1.14.0 is reserved for Marine Oil Terminals regulated by the California State Lands Commis- sion.

1.1.4 Appendices. Provisions contained in the appendices of this code shall not apply unless specifically adopted by a state agency or adopted by a local enforcing agency in compliance with Health and Safety Code Section 18901 et. seq. for Building Standards Law, Health and Safety Code Section 17950 for State Housing Law and Health and Safety Code Section 13869.7 for Fire Protection Districts. See Section 1.1.8 of this code.

1.1.5 Referenced Codes. The codes, standards and publica- tions adopted and set forth in this code, including other codes, standards, and publications referred to therein are, by title and date of publication, hereby adopted as standard refer- ence documents of this code. When this code does not specif- ically cover any subject related to building design and construction, recognized architectural, or engineering prac- tices shall be employed. The National Fire Codes, standards, and the Fire Protection Handbook of the National Fire Protection Association are permitted to be used as authori- tative guides in determining recognized fire prevention engi- neering practices.

not specif-_ ically cover any subject related to building design and construction, recognized architectural, or engineering prac- tices shall be employed. The National Fire Codes, standards, and the Fire Protection Handbook of the National Fire Protection Association are permitted to be used as authori- tative guides in determining recognized fire prevention engi- neering practices.

1.1.6 NonBuilding Standards, Orders and Regulations. Requirements contained in the Uniform Mechanical Code, or in any other referenced standard, code or document, which are not building standards as defined in Health and Safety Code Section 18909, shall not be construed as part of the provisions of this code. For nonbuilding standards, orders, and regulations, see other titles of the California Code of Regulations.

1.1.7 Order of Precedence and Use.

1.1.7.1 Differences. In the event of any differences between these building standards and the standard refer- ence documents, the text of these building standards shall

govern.

1.1.7.2 Specific Provisions. Where a specific provision varies from a general provision, the specific provision shall apply.

1.1.7.3 Conflicts. When the requirements of this code conflict with the requirements of any other part of the California Building Standards Code, Title 24, the most restrictive requirements shall prevail.

1.1.7.3.1 Detached One- and Two-Family Dwellings. Detached one- and two-family dwellings, efficiency dwelling units, lodging houses, live/work units, townhouses not more than three stories above grade plane in height with a separate means of egress, and their accessory structures, shall not be required to comply with the California Residential Code if constructed in accordance with the California Building Code.

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1.1.8 City, County, or City and County Amendments, Additions or Deletions. The provisions of this code do not limit the authority of city, county, or city and county governments to establish more restrictive and reasonably necessary differences to the provisions contained in this code pursuant to complying with Section 1.1.8.1. The effective date of amendments, addi- tions, or deletions to this code by a city, county, or city and county filed pursuant to Section 1.1.8.1 shall be the date filed. However, in no case shall the amendments, additions, or dele- tions to this code be effective any sooner than the effective date of this code.

Local modifications shall comply with Health and Safety Code Section 18941.5 for Building Standards Law, Health and Safety Code Section 17958 for State Housing Law or Health and Safety Code Section 13869.7 for Fire Protection Districts.

1.1.8.1 Findings and Filings.

(1) The city, county, or city and county shall make express findings for each amendment, addition, or deletion based upon climatic, topographical, or geological conditions.

Exception: Hazardous building ordinances and programs mitigating unreinforced masonry build- ings.

(2) The city, county, or city and county shall file the amendments, additions or deletions expressly marked and identified as to the applicable findings. Cities, counties, cities and counties, and fire depart- ments shall file the amendments, additions, or dele- tions, and the findings with the California Building Standards Commission at 2525 Natomas Park

Drive, Suite 130, Sacramento, CA 95833.

(3) Findings prepared by fire protection districts shall be ratified by the local city, county, or city and county and filed with the California Department of Housing and Community Development, Division of Codes and Standards, P.O. Box 278180, Sacra- mento, CA 95827-8180 or 9342 Tech Center Drive, Suite 500, Sacramento, CA, 95826-2582.

1.1.8.2 California Energy Code Requirements for Locally Adopted Energy Standards. In addition to the provisions of Section 1.1.8.1 of this part, local jurisdic- tions that adopt changes to energy conservation or insu- lation standards (including energy efficiency measures) may not enforce such changes until the California Energy Commission has made the findings required by Public Resources Code Section 25402.1(h)(2), following the process specified in Section 10-106 of the California Administrative Code.

1.1.9 Effective Date of This Code. Only those standards approved by the California Building Standards Commission that are effective at the time an application for building permit is submitted shall apply to the plans and specifications for, and to the construction performed under, that permit. For the effective dates of the provisions contained in this code, see the History Note page of this code.

Exceptions: (1) [HCD 1 & HCD 2] Retroactive permits issued in accor- dance with Health and Safety Code Section 17958.12.

(2) [HCD 1 & HCD 2] Plans approved by the Department of Housing and Community Development or a Department- approved design approval agency for factory-built housing as defined by Health and Safety Code Section 19971. Approved plans, pursuant to the California Code of Regu- lations, Title 25, Division 1, Chapter 3, Subchapter 1, Article 3, Section 3037 remain valid for a period of 36 months from the date of plan approval.

1.1.10 Availability of Codes. At least one complete copy each of Titles 8, 19, 20, 24, and 25 with all revisions shall be main- tained in the office of the building official responsible for the administration and enforcement of this code. Each state department concerned and each city, county, or city and county shall have an up-to-date copy of the code available for public inspection, see Health and Safety Code Section 18942(e)(1) and (2).

ach_ of Titles 8, 19, 20, 24, and 25 with all revisions shall be main- tained in the office of the building official responsible for the administration and enforcement of this code. Each state department concerned and each city, county, or city and county shall have an up-to-date copy of the code available for public inspection, see Health and Safety Code Section 18942(e)(1) and (2).

1.1.11 Format. This part fundamentally adopts the Uniform Mechanical Code by reference on a chapter-by-chapter basis. When a specific chapter of the Uniform Mechanical Code is not printed in the code and is marked “Reserved”, such chapter of the Uniform Mechanical Code is not adopted as a portion of this code. When a specific chapter of the Uniform Mechanical Code is marked “Not adopted by the State of California” but appears in the code, it may be available for adoption by local ordinance.

Note: Matrix Adoption Tables at the front of each chapter may aid the code user in determining which chapter or sections within a chapter are applicable to buildings under the authority of a specific state agency, but they are not to be considered regulatory.

1.1.12 Validity. If any chapter, section, subsection, sentence, clause, or phrase of this code is for any reason held to be unconstitutional, contrary to statute, exceeding the authority of the state as stipulated by statutes or otherwise inoperative, such decision shall not affect the validity of the remaining portion of this code.

1.2.0 Building Standards Commission.

1.2.1 BSC. Specific scope of application of the agency responsible for enforcement, the enforcement agency, and the specific authority to adopt and enforce such provisions of this code, unless otherwise stated.

(1) State Buildings for All Occupancies.

Application – State buildings (all occupancies), including buildings constructed by the Trustees of the California State University (CSU) and the Regents of the University of California (UC) where no state agency has the authority to adopt building standards applicable to such buildings.

Enforcing Agency – State or local agency specified by the applicable provisions of law.

Authority Cited – Health and Safety Code Section 18934.5.

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Reference – Health and Safety Code, Division 13, Part 2.5, commencing with Section 18901.

(2) University of California, California State Universities, and California Community Colleges.

Application – Standards for lighting for parking lots and primary campus walkways at the University of Cali- fornia, California State Universities, and California Community Colleges.

Enforcing Agency – State or local agency specified by the applicable provisions of law.

Authority Cited – Government Code Section 14617.

Reference – Government Code Section 14617.

(3) Existing State-Owned Buildings, including those owned by the University of California and by the Cali- fornia State University – Building seismic retrofit stan- dards including abating falling hazards of structural and nonstructural components and strengthening of building structures. See also Division of the State Architect.

Enforcing Agency – State or local agency specified by the applicable provisions of law.

Authority Cited – Government Code Section 16600.

References – Government Code Sections 16600 through 16604.

(4) Unreinforced Masonry Bearing Wall Buildings.

Application – Minimum seismic strengthening standards for buildings specified in the California Existing Building Code, except for buildings subject to building standards adopted pursuant to Part 1.5 (commencing with Section 17910).

Enforcing Agency – State or local agency specified by the applicable provisions of law.

Authority Cited – Health and Safety Code Section 18934.7.

References – Health and Safety Code Division 13, Part 2.5 commencing with Sections 18901.

1.2.1.1 State Building. For purposes of this code, a “state building” is a structure for which a state agency or state entity has authority to construct, alter, enlarge, replace, repair or demolish.

1.2.1.2 Enforcement. [CSU, UC, Judicial Council & California Department of Corrections and Rehabilita- tion] state agencies or state entities authorized to construct state buildings may appoint a building official who is responsible to the agency for enforcement of the provisions of the California Building Standards Code.

Exception: State buildings regulated by other sections of this code remain the enforcement responsibility of the designated entities.

1.2.1.3 Enforcement, Reserved for DGS.

1.2.1.4 Adopting Agency Identification. The provisions of this code applicable to buildings identified in this section will be identified in the Matrix Adoption Tables under the acronym BSC.

1.2.2 BSC-CG. Specific scope of application of the agency responsible for enforcement, the enforcement agency, and the specific authority to adopt and enforce such provisions of this code, unless otherwise stated.

(1) Green Building Standards for Nonresidential Occu- pancies.

Application – All occupancies where no other state agency has the authority to adopt green building stan- dards applicable to those occupancies.

Enforcing Agency – State or local agency specified by the applicable provisions of law.

Authority Cited – Health and Safety Code Sections 18930.5, 18938 and 18940.5.

Reference – Health and Safety Code, Division 13, Part 2.5, commencing with Section 18901.

(2) Graywater Systems for Nonresidential Occupancies.

Application – The construction, installation, and alter- ation of graywater systems for indoor and outdoor uses in nonresidential occupancies.

Enforcing Agency – State or local agency specified by the applicable provisions of law.

Authority Cited – Health & Safety Code Section 18941.8.

Reference – Health & Safety Code Section 18941.8.

1.2.3 Alternative Materials, Design, and Methods of Construction and Equipment. The provisions of this code are not intended to prevent the installation of any material or to prohibit any design or method of construction not specifically prescribed by this code, provided that any such alternative has been approved. An alternative material, design, or method of construction shall be approved where the building official finds that the proposed design is satisfactory and complies with the intent of the provisions of this code, and that the material, method or work offered is, for the purpose intended, at least the equivalent of that prescribed in this code in quality, strength, effectiveness, fire resistance, durability and safety.

1.2.3.1 Research Reports. Supporting data, where neces- sary to assist in the approval of materials or assemblies not specifically provided for in this code, shall consist of valid research reports from approved sources.

1.2.3.2 Tests. Whenever there is insufficient evidence of compliance with the provisions of this code, or evidence that a material or method does not conform to the require- ments of this code, or in order to substantiate claims for alternative materials or methods, the building official shall have the authority to require tests as evidence of compli- ance to be made at no expense to the jurisdiction. Test methods shall be as specified in this code or by other recog- nized test standards. In the absence of recognized and accepted test methods, the building official shall approve the testing procedures. Tests shall be performed by an approved agency. Reports of such tests shall be retained by the building official for the period required for retention of public records.

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1.3.0 Reserved for Board of State and Community Correc- tions.

1.4.0 Department of Consumer Affairs.

1.4.1 Specific scope of application of the agency responsible for enforcement, the enforcement agency, and the specific authority to adopt and enforce such provisions of this code, unless otherwise stated.

Board of Pharmacy.

Application – Pharmacies.

Enforcing Agency – State or local agency specified by applicable provisions of law.

Authority Cited – Business and Professions Code Section 4005.

References – Business and Professions Code Sections 4005, 4127.7, and 4201.

1.4.2 Adopting Agency Identification. The provisions of this code applicable to buildings identified in this section will be identified in the Matrix Adoption Tables under the acronym CA.

1.5.0 Reserved for California Energy Commission.

1.6.0 Reserved for Department of Food and Agriculture.

1.7.0 California Department of Public Health.

1.7.1 Specific scope of application of the agency responsible for enforcement, the enforcement agency, and the specific authority to adopt and enforce such provisions of this code, unless otherwise stated.

Department of Public Health.

Application – Food establishments.

Enforcing Agency – Department of Health Services and the local health agency.

Authority Cited – Health and Safety Code Sections 110065, 113710, and 131200.

References – Health and Safety Code Sections 110065, 113705, 114140, and 131200.

1.7.2 Adopting Agency Identification. The provisions of this code applicable to buildings identified in this section will be identified in the Matrix Adoption Tables under the acronym DPH.

1.8.0 Department of Housing and Community Development.

[HCD]

1.8.1 Purpose. The purpose of this code is to establish the minimum requirements necessary to protect the health, safety, and general welfare of the occupants and the public by governing the erection, construction, reconstruction, enlarge- ment, conversion, alteration, repair, moving, removal, demo- lition, ventilation, and maintenance or use of heating, ventilating, cooling, refrigeration systems, incinerators, and other miscellaneous heat-producing appliances.

1.8.2 Authority and Abbreviations.

1.8.2.1 General. The Department of Housing and Community Development is authorized by law to prom- ulgate and adopt building standards and regulations for several types of building applications. The applications under the authority of the Department of Housing and Community Development are listed in Sections 1.8.2.1.1 through 1.8.2.1.3.

1.8.2.1.1 Housing Construction.

Application – Hotels, motels, lodging houses, apart- ments, dwellings, dormitories, condominiums, shel- ters for homeless persons, congregate residences, employee housing, factory-built housing, and other types of dwellings containing sleeping accommoda- tions with or without common toilet or cooking facil- ities including accessory buildings, facilities, and uses thereto. Sections of this code which pertain to applications listed in this section are identified using the abbreviation “HCD 1.”

Enforcing Agency – Local building department or the Department of Housing and Community Devel- opment.

Authority Cited – Health and Safety Code Sections 17040, 17920.9, 17921, 17921.5, 17921.6, 17921.10, 17922, 17922.6, 17922.12, 17922.14, 17922.15, 17926, 17927, 17928, 17958.12, 18938.3, 18944.11, and 19990; and Government Code Section 12955.1.

References – Business and Professions Code Divi- sion 5; Health and Safety Code Sections 17000 through 17062.5, 17910 through 17995.5, 18200 through 18700, 18860 through 18874, 18938.6, 18941, 19890, 19891, 19892 and 19960 through 19997; Civil Code Sections 832, 1101.4, 1101.5, 1954.201, 1954.202 and 5551; and Government Code Sections 8698.4, 12955.1 and 12955.1.1. Cali- fornia Code of Regulations, Title 20, Sections 1605.1, 1605.3 and 1607.

1.8.2.1.2 Housing Accessibility.

Application – Covered multifamily dwellings as defined in Chapter 2 of the California Code of Regu- lations, Title 24, Part 2, also known as the California Building Code including, but not limited to, lodging houses, dormitories, timeshares, condominiums, shel- ters for homeless persons, congregate residences, apartments, dwellings, employee housing, factory- built housing, and other types of dwellings containing sleeping accommodations with or without common toilet or cooking facilities.

Sections of this code identified by the abbrevia- tion “HCD 1-AC” require specific accommodations for persons with disabilities as defined in Chapter 2 of the California Building Code. The application of such provisions shall be in conjunction with other requirements of this code and apply only to newly- constructed covered multifamily dwellings as defined in Chapter 2 of the California Building Code. “HCD 1-AC” applications include, but are not limited to, the following:

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(1) All newly-constructed covered multifamily dwellings as defined in Chapter 2 of the Cali- fornia Building Code.

(2) New common use areas as defined in Chapter 2 of the California Building Code serving existing covered multifamily dwellings.

(3) Additions to existing buildings, where the addi- tion alone meets the definition of covered multi- family dwellings as defined in Chapter 2 of the California Building Code.

(4) New common use areas serving new covered multifamily dwellings.

(5) Where any portion of a building’s exterior is preserved, but the interior of the building is removed, including all structural portions of floors and ceilings, the building is considered a new building for determining the application of California Building Code, Chapter 11A.

“HCD 1-AC” building standards generally do not apply to public use areas or public accommodations such as hotels and motels, and public housing. Public use areas, public accommodations, and public housing, as defined in Chapter 2 of the Cali- fornia Building Code, are subject to the Division of the State Architect (DSA-AC) in Chapter 11B, and are referenced in Section 1.9.1.

Newly constructed covered multifamily dwellings, which can also be defined as public housing, shall be subject to the requirements of Chapter 11A and Chapter 11B.

Enforcing Agency – Local building department or the Department of Housing and Community Devel- opment.

Authority Cited – Health and Safety Code Sections 17040, 17920.9, 17921, 17921.5, 17921.6, 17921.10, 17922, 17922.6, 17922.12, 17922.14, 17926, 17927, 17928, 17958.12, 18938.3, 18944.11, and 19990; and Government Code Section 12955.1 and 12955.1.1.

References – Health and Safety Code Sections 17000 through 17062.5, 17910 through 17995.5, 18200 through 18700, 18860 through 18874, 18938.6, 18941 and 19960 through 19997; Civil Code Sections 1101.4, 1101.5, 1954.201, 1954.202; and Government Code Sections 12955.1 and 12955.1.1. California Code of Regulations, Title 20, Sections 1605.1, 1605.3 and 1607.

1.8.2.1.3 Permanent Buildings in Mobilehome Parks and Special Occupancy Parks.

Application – Permanent buildings, and permanent accessory buildings or structures, constructed within mobilehome parks and special occupancy parks that are under the control and ownership of the park operator. Sections of this code which pertain to applications listed in this section are iden- tified using the abbreviation “HCD 2.”

Enforcing Agency – The Department of Housing and Community Development, local building depart- ment or other local agency that has assumed respon- sibility for the enforcement of Health and Safety Code, Division 13, Part 2.1, commencing with Section 18200 for mobilehome parks and Health and Safety Code, Division 13, Part 2.3, commencing with Section 18860 for special occupancy parks.

Authority Cited – Health and Safety Code Sections 17040, 17920.9, 17921, 17921.5, 17921.6, 17921.10, 17922, 17922.6, 17922.12, 17922.14, 17922.15, 17926, 17927, 17928, 17958.12, 18552, 18554, 18620, 18630, 18640, 18670, 18690, 18691, 18865, 18871.3, 18871.4, 18873, 18873.1 through 18873.5, 18938.3, 18944.11, and 19990; and Government Code Section 12955.1.

References – Health and Safety Code Sections 17000 through 17062.5, 17910 through 17995.5, 18200 through 18700, 18860 through 18874, 18938.6, 18941, 19890, 19891, 19892 and 19960 through 19997; Civil Code Sections 1101.4, 1101.5 and 1954.201; and Government Code Sections 12955.1 and 12955.1.1. California Code of Regula- tions, Title 20, Sections 1605.1, 1605.3 and 1607; and Title 25, Sections 1042 and 2042.

1.8.3 Local Enforcing Agency.

1.8.3.1 Duties and Powers. The building department of every city, county, or city and county shall enforce all the provisions of law, this code, and the other rules and regu- lations promulgated by the Department of Housing and Community Development pertaining to the installation, erection, construction, reconstruction, movement, enlargement, conversion, alteration, repair, removal, demolition, or arrangement of apartments, condo- miniums, hotels, motels, lodging houses, and dwellings, including accessory buildings, facilities, and uses thereto.

The provisions regulating the erection and construc- tion of dwellings and appurtenant structures shall not apply to existing structures as to which construction is commenced or approved prior to the effective date of these regulations. Requirements relating to use, mainte- nance, and occupancy shall apply to all dwellings and appurtenant structures approved for construction or constructed before or after the effective date of this code.

ion of dwellings and appurtenant structures shall not_ apply to existing structures as to which construction is commenced or approved prior to the effective date of these regulations. Requirements relating to use, mainte- nance, and occupancy shall apply to all dwellings and appurtenant structures approved for construction or constructed before or after the effective date of this code.

For additional information regarding the use and occupancy of existing buildings and appurtenant structures, see California Code of Regulations, Title 25, Division 1, Chapter 1, Subchapter 1, commencing with Section 1.

1.8.3.2 Laws, Rules, and Regulations. Other than the building standards contained in this code, and notwith- standing other provisions of law, the statutory authority and location of the laws, rules, and regulations to be enforced by local enforcing agencies are listed by statute in Sections 1.8.3.2.1 through 1.8.3.2.5.

1.8.3.2.1 State Housing Law. Refer to the State Housing Law, California Health and Safety Code, Division 13, Part 1.5, commencing with Section 17910, and California Code of Regulations, Title 25,

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Division 1, Chapter 1, Subchapter 1, commencing with Section 1, for the erection, construction, recon- struction, movement, enlargement, conversion, alter- ation, repair, removal, demolition, or arrangement of apartments, condominiums, hotels, motels, lodging houses, and dwellings, including accessory buildings, facilities, and uses thereto.

1.8.3.2.2 Mobilehome Parks Act. Refer to the Mobilehome Parks Act, California Health and Safety Code, Division 13, Part 2.1, commencing with Section 18200 and California Code of Regula- tions, Title 25, Division 1, Chapter 2, commencing with Section 1000 for mobilehome park administra- tive and enforcement authority, permits, plans, fees, violations, inspections, and penalties both within and outside mobilehome parks. Exception: Mobilehome parks where the Depart- ment of Housing and Community Development is the enforcing agency. 1.8.3.2.3 Special Occupancy Parks Act. Refer to the Special Occupancy Parks Act, California Health and Safety Code, Division 13, Part 2.3, commencing with Section 18860 and California Code of Regulations, Title 25, Division 1, Chapter 2.2, commencing with Section 2000 for special occupancy park administra- tive and enforcement authority, permits, fees, viola- tions, inspections, and penalties both within and outside of special occupancy parks. Exception: Special occupancy parks where the Department of Housing and Community Develop- ment is the enforcing agency. 1.8.3.2.4 Employee Housing Act. Refer to the Employee Housing Act, California Health and Safety Code, Division 13, Part 1, commencing with Section 17000 and California Code of Regulations, Title 25, Division 1, Chapter 1, Subchapter 3, commencing with Section 600 for employee housing administrative and enforcement authority, permits, fees, violations, inspections, and penalties. 1.8.3.2.5 Factory-Built Housing Law. Refer to the Factory-Built Housing Law, California Health and Safety Code, Division 13, Part 6, commencing with Section 19960 and California Code of Regulations, Title 25, Division 1, Chapter 3, Subchapter 1, commencing with Section 3000 for factory-built housing administrative and enforcement authority, permits, fees, violations, inspections, and penalties. 1.8.4 Permits, Fees, Applications, and Inspections. 1.8.4.1 Permits. A written construction permit shall be obtained from the enforcing agency prior to the erection, construction, reconstruction, installation, relocation, or alteration of any mechanical system. Exceptions: (1) Work exempt from permits as specified in Chapter 1, Scope and Administration, Division II, Section

(2) Changes, alterations, or repairs of a minor nature not affecting structural features, egress, sanitation, safety, or accessibility as determined by the enforcing agency.

(3) Retroactive permits issued in accordance with Health and Safety Code Section 17958.12.

Exemptions from permit requirements shall not be deemed to grant authorization for any work to be done in any manner in violation of other provisions of law or this code. 1.8.4.2 Fees. Subject to other provisions of law, the governing body of any city, county, or city and county may prescribe fees to defray the cost of enforcement of rules and regulations promulgated by the Department of Housing and Community Development. The amount of the fees shall not exceed the amount reasonably neces- sary to administer or process permits, certificates, forms, or other documents, or to defray the costs of enforcement. For additional information, see State Housing Law, Health and Safety Code, Division 13, Part 1.5, Section 17951 and California Code of Regulations, Title 25, Divi- sion 1, Chapter 1, Subchapter 1, Article 3, commencing with Section 6.

ed the amount reasonably neces-_ sary to administer or process permits, certificates, forms, or other documents, or to defray the costs of enforcement. For additional information, see State Housing Law, Health and Safety Code, Division 13, Part 1.5, Section 17951 and California Code of Regulations, Title 25, Divi- sion 1, Chapter 1, Subchapter 1, Article 3, commencing with Section 6.

1.8.4.3 Plan Review and Time Limitations. Subject to other provisions of law, provisions related to plan checking, prohibition of excessive delays, and contracting with or employment of private parties to perform plan checking are set forth in the State Housing Law, Health and Safety Code Section 17960.1, and for employee housing, in Health and Safety Code Section 17021. 1.8.4.3.1 Retention of Plans. The building depart- ment of every city, county, or city and county shall maintain an official copy, microfilm, or electronic or other type of photographic copy of the plans of every building, during the life of the building, for which the department issued a building permit. Exceptions: (1) Single or multiple dwellings not more than two stories and basement in height. (2) Garages and other structures appurtenant to buildings listed in Exception 1. (3) Farm or ranch buildings appurtenant to build- ings listed in Exception 1. (4) Any one-story building where the span between bearing walls does not exceed 25 feet (7620 mm), except a steel frame or concrete building. All plans for common interest developments as defined in Section 4100 of the California Civil Code shall be retained. For additional information regarding plan retention and reproduction of plans by an enforcing agency, see Health and Safety Code Sections 19850 through 19852. 1.8.4.4 Inspections. Construction or work for which a permit is required shall be subject to inspection by the building official and such construction or work shall remain accessible and exposed for inspection purposes until approved. Approval as a result of an inspection shall not be construed to be an approval of a violation of the provisions of this code or other regulations of the Department of Housing and Community Development. 1.8.5 Right of Entry for Enforcement. 1.8.5.1 General. Subject to other provisions of law, offi- cers and agents of the enforcing agency may enter and

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inspect public and private properties to secure compli- ance with the rules and regulations promulgated by the Department of Housing and Community Development. For limitations and additional information regarding enforcement, see the following:

(1) For applications subject to State Housing Law as referenced in Section 1.8.3.2.1 of this code, refer to Health and Safety Code, Division 13, Part 1.5, commencing with Section 17910 and California Code of Regulations, Title 25, Division 1, Chapter 1, Subchapter 1, commencing with Section 1.

(2) For applications subject to the Mobilehome Parks Act as referenced in Section 1.8.3.2.2 of this code, refer to Health and Safety Code, Division 13, Part 2.1, commencing with Section 18200, and California Code of Regulations, Title 25, Division 1, Chapter 2, commencing with Section 1000.

(3) For applications subject to the Special Occupancy Parks Act as referenced in Section 1.8.3.2.3 of this code, refer to Health and Safety Code, Division 13, Part 2.3, commencing with Section 18860, and Cali- fornia Code of Regulations, Title 25, Division 1, Chapter 2.2, commencing with Section 2000.

(4) For applications subject to the Employee Housing Act as referenced in Section 1.8.3.2.4 of this code, refer to Health and Safety Code, Division 13, Part 1, commencing with Section 17000 and California Code of Regulations, Title 25, Division 1, Chapter 1, Subchapter 3, commencing with Section 600.

(5) For applications subject to the Factory-Built Housing Law as referenced in Section 1.8.3.2.5 of this code, refer to Health and Safety Code, Division 13, Part 6, commencing with Section 19960 and California Code of Regulations, Title 25, Division 1, Chapter 3, Subchapter 1, commencing with Section 3000.

1.8.6 Local Modification by Ordinance or Regulation.

1.8.6.1 General. Subject to other provisions of law, a city, county, or city and county may make changes to the provi- sions adopted by the Department of Housing and Community Development. If any city, county, or city and county does not amend, add, or repeal by local ordi- nances or regulations the provisions published in this code or other regulations promulgated by the Department of Housing and Community Development, those provi- sions shall be applicable and shall become effective 180 days after publication by the California Building Stan- dards Commission. Amendments, additions, and deletions to this code adopted by a city, county, or city and county pursuant to California Health and Safety Code Sections 17958.5, 17958.7 and 18941.5, together with all appli- cable portions of this code, shall also become effective 180 days after publication of the California Building Standards Code by the California Building Standards Commission.

1.8.6.2 Findings, Filings, and Rejections of Local Modifications. Prior to making any modifications or establishing more restrictive building standards, the governing body shall make express findings and filings,

as required by California Health and Safety Code Section 17958.7, showing that such modifications are reasonably necessary due to local climatic, geological, or topo- graphical conditions. No modification shall become effective or operative unless the following requirements

are met:

(1) The express findings shall be made available as a public record.

(2) A copy of the modification and express finding, each document marked to cross-reference the other, shall be filed with the California Building Standards Commission for a city, county, or city and county, and with the Department of Housing and Commu- nity Development for fire protection districts.

(3) The California Building Standards Commission has not rejected the modification or change.

Nothing in this section shall limit the authority of fire protection districts pursuant to California Health and Safety Code Section 13869.7(a).

1.8.7 Alternate Materials, Designs, Tests, and Methods of Construction.

1.8.7.1 General. The provisions of this code as adopted by the Department of Housing and Community Develop- ment are not intended to prevent the use of any alternate material, appliance, installation, device, arrangement, design, or method of construction not specifically prescribed by this code. Consideration and approval of alternates shall comply with Section 1.8.7.2 for local building departments and Section 1.8.7.3 for the Depart- ment of Housing and Community Development.

1.8.7.2 Local Building Departments. The building department of any city, county, or city and county may approve alternates for use in the erection, construction, reconstruction, movement, enlargement, conversion, alteration, repair, removal, demolition, or arrangement of apartments, condominiums, hotels, motels, lodging houses, dwellings, or accessory structures, except for the following:

(1) Structures located in mobilehome parks as defined in California Health and Safety Code Section 18214.

(2) Structures located in special occupancy parks as defined in California Health and Safety Code Section 18862.43.

(3) Factory-built housing as defined in California Health and Safety Code Section 19971.

1.8.7.2.1 Approval of Alternates. The consideration and approval of alternates by a local building department shall comply with the following proce- dures and limitations:

(1) The approval shall be granted on a case-by- case basis.

(2) Evidence shall be submitted to substantiate claims that the proposed alternate, in perform- ance, safety, and protection of life and health,

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conforms to, or is at least equivalent to, the standards contained in this code and other rules and regulations promulgated by the Department of Housing and Community Development.

(3) The local building department may require tests performed by an approved testing agency at the expense of the owner or owner’s agent as proof of compliance.

(4) If the proposed alternate is related to accessi- bility in covered multifamily dwellings or facili- ties serving covered multifamily dwellings as defined in Chapter 2 of the California Building Code, the proposed alternate must also meet the threshold set for equivalent facilitation as defined in Chapter 2 of the California Building Code.

For additional information regarding approval of alternates by a local building department pursuant to the State Housing Law, see California Health and Safety Code Section 17951(e) and Cali- fornia Code of Regulations, Title 25, Division 1, Chapter 1, Subchapter 1.

1.8.7.3 Department of Housing and Community Devel- opment. The Department of Housing and Community Development may approve alternates for use in the erec- tion, construction, reconstruction, movement, enlarge- ment, conversion, alteration, repair, removal, or demolition of apartments, condominiums, hotels, motels, lodging houses, dwellings, or accessory structures thereto, and permanent buildings in mobilehome parks and special occupancy parks. The consideration and approval of alter- nates shall comply with the following:

(1) The department may require tests at the expense of the owner or owner’s agent to substantiate compli- ance with the California Building Standards Code.

(2) The approved alternate shall, for its intended purpose, be at least equivalent in performance and safety to the materials, designs, tests, or methods of construction prescribed by this code.

1.8.8 Appeals Board.

1.8.8.1 General. Every city, county, or city and county shall establish a process to hear and decide appeals of orders, decisions, and determinations made by the enforcing agency relative to the application and interpretation of this code and other regulations governing construction, use, maintenance and change of occupancy. The governing body of any city, county, or city and county may establish a local appeals board and a housing appeals board to serve this purpose. Members of the appeals board(s) shall not be employees of the enforcing agency and shall be knowl- edgeable in the applicable building codes, regulations and ordinances as determined by the governing body of the city, county, or city and county.

Where no such appeals boards or agencies have been established, the governing body of the city, county, or city and county shall serve as the local appeals board or housing appeals board as specified in California Health and Safety Code Sections 17920.5 and 17920.6.

1.8.8.2 Definitions. The following terms shall for the purposes of this section have the meaning shown.

Housing Appeals Board. The board or agency of a city, county, or city and county which is authorized by the governing body of the city, county, or city and county to hear appeals regarding the requirements of the city, county, or city and county relating to the use, mainte- nance, and change of occupancy of buildings and struc- tures, including requirements governing alteration, additions, repair, demolition, and moving. In any area in which there is no such board or agency, “Housing Appeals Board” means the local appeals board having jurisdiction over the area.

Local Appeals Board. The board or agency of a city, county, or city and county which is authorized by the governing body of the city, county, or city and county to hear appeals regarding the building requirements of the city, county, or city and county. In any area in which there is no such board or agency, “Local Appeals Board” means the governing body of the city, county, or city and county having jurisdiction over the area.

1.8.8.3 Appeals. Except as otherwise provided by law, any person, firm, or corporation adversely affected by a decision, order, or determination by a city, county, or city and county relating to the application of building stan- dards published in the California Building Standards Code, or any other applicable rule or regulation adopted by the Department of Housing and Community Develop- ment, or any lawfully enacted ordinance by a city, county, or city and county, may appeal the issue for resolution to the local appeals board or housing appeals board as appropriate.

The local appeals board shall hear appeals relating to new building construction and the housing appeals board shall hear appeals relating to existing buildings.

1.8.9 Unsafe Buildings or Structures.

1.8.9.1 Authority to Enforce. Subject to other provisions of law, the administration, enforcement, actions, proceed- ings, abatement, violations, and penalties for unsafe buildings and structures are contained in the following statutes and regulations:

(1) For applications subject to the State Housing Law as referenced in Section 1.8.3.2.1 of this code, refer to Health and Safety Code, Division 13, Part 1.5, commencing with Section 17910 and California Code of Regulations, Title 25, Division 1, Chapter 1, Subchapter 1, commencing with Section 1. For enforcement related to accessory dwelling units, see Health and Safety Code Section 17980.12 operative until January 1, 2035.

(2) For applications subject to the Mobilehome Parks Act as referenced in Section 1.8.3.2.2 of this code, refer to Health and Safety Code, Division 13, Part 2.1, commencing with Section 18200 and California Code of Regulations, Title 25, Division 1, Chapter 2, commencing with Section 1000.

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(3) For applications subject to the Special Occupancy Parks Act as referenced in Section 1.8.3.2.3 of this code, refer to Health and Safety Code, Division 13, Part 2.3, commencing with Section 18860 and Cali- fornia Code of Regulations, Title 25, Division 1, Chapter 2.2, commencing with Section 2000. (4) For applications subject to the Employee Housing Act as referenced in Section 1.8.3.2.4 of this code, refer to Health and Safety Code, Division 13, Part 1, commencing with Section 17000 and California Code of Regulations, Title 25, Division 1, Chapter 1, Subchapter 3, commencing with Section 600. (5) For applications subject to the Factory-Built Housing Law as referenced in Section 1.8.3.2.5 of this code, refer to Health and Safety Code, Division 13, Part 6, commencing with Section 19960 and California Code of Regulations, Title 25, Division 1, Chapter 3, Subchapter 1, commencing with Section 3000. 1.8.9.2 Actions and Proceedings. Subject to other provi- sions of law, punishments, penalties, and fines for viola- tions of building standards are contained in the following statutes and regulations: (1) For applications subject to the State Housing Law as referenced in Section 1.8.3.2.1 of this code, refer to Health and Safety Code, Division 13, Part 1.5, commencing with Section 17910 and California Code of Regulations, Title 25, Division 1, Chapter 1, Subchapter 1, commencing with Section 1. (2) For applications subject to the Mobilehome Parks Act as referenced in Section 1.8.3.2.2 of this code, refer to Health and Safety Code, Division 13, Part 2.1, commencing with Section 18200 and California Code of Regulations, Title 25, Division 1, Chapter 2, commencing with Section 1000. (3) For applications subject to the Special Occupancy Parks Act as referenced in Section 1.8.3.2.3 of this code, refer to Health and Safety Code, Division 13, Part 2.3, commencing with Section 18860 and Cali- fornia Code of Regulations, Title 25, Division 1, Chapter 2.2, commencing with Section 2000. (4) For applications subject to the Employee Housing Act as referenced in Section 1.8.3.2.4 of this code, refer to Health and Safety Code, Division 13, Part 1, commencing with Section 17000 and California Code of Regulations, Title 25, Division 1, Chapter 1, Subchapter 3, commencing with Section 600. (5) For applications subject to the Factory-Built Housing Law as referenced in Section 1.8.3.2.5 of this code, refer to Health and Safety Code, Division 13, Part 6, commencing with Section 19960 and California Code of Regulations, Title 25, Division 1, Chapter 3, Subchapter 1, commencing with Section 3000. 1.8.10 Other Building Regulations. 1.8.10.1 Existing Structures. Notwithstanding other provisions of law, the replacement, retention, and exten- sion of original materials and the use of original methods of construction for any existing building or accessory structure, or portions thereof, shall be permitted in accor-

Chapter 3,_ Subchapter 1, commencing with Section 3000. 1.8.10 Other Building Regulations. 1.8.10.1 Existing Structures. Notwithstanding other provisions of law, the replacement, retention, and exten- sion of original materials and the use of original methods of construction for any existing building or accessory structure, or portions thereof, shall be permitted in accor-

dance with the provisions of this code and the California Existing Building Code, as adopted by the Department of Housing and Community Development. For additional information, see California Health and Safety Code, Sections 17912, 17920.3, 17922 and 17958.8.

1.8.10.2 Moved Structures. Subject to the requirements of California Health and Safety Code Sections 17922, 17922.3 and 17958.9, local ordinances or regulations relating to a moved residential building or accessory structure thereto, shall permit the replacement, retention, and extension of original materials and the use of original methods of construction so long as the structure does not become or continue to be a substandard building.

1.9.0 Division of the State Architect. 1.9.1 Reserved for the Division of the State Architect – Access Compliance. 1.9.2 Division of the State Architect – Structural Safety. 1.9.2.1 DSA-SS (Division of the State Architect – Struc- tural Safety).

– Application Public elementary and secondary schools, community college buildings, and state-owned or state- leased essential services buildings.

– Enforcing Agency Division of the State Architect – Structural Safety (DSA-SS). The Division of the State Architect has been delegated the responsibility and authority by the Department of General Services to review and approve the design and oversee and observe the construction of public elementary and secondary schools, community colleges, and state- owned or state-leased essential services buildings. Authority Cited – Education Code Sections 17310 and 81142, and Health & Safety Code Section 16022.

– References Education Code Sections 17280 through 17317 and 81130 through 81147, and Health & Safety Code Sections 16000 through 16023. 1.9.2.1.1 Adopting Agency Identification. The provi- sions of this code applicable to buildings identified in this Subsection 1.9.2.1 will be identified in the Matrix Adoption Tables under the acronym DSA-SS. 1.9.2.2 DSA-SS/CC (Division of the State Architect – Structural Safety/Community Colleges).

– Application Community Colleges. The Division of the State Architect has been delegated the authority by the Department of General Services to promulgate alternate building standards for application to community colleges, which a community college may elect to use in lieu of standards promulgated by DSA-SS, in accordance with Section 1.9.2.1. Refer to Title 24, Part 2, Section 1.9.2.2.

ation**_ Community Colleges. The Division of the State Architect has been delegated the authority by the Department of General Services to promulgate alternate building standards for application to community colleges, which a community college may elect to use in lieu of standards promulgated by DSA-SS, in accordance with Section 1.9.2.1. Refer to Title 24, Part 2, Section 1.9.2.2.

– Enforcing Agency Division of the State Architect – Structural Safety/Community Colleges (DSA-SS/CC). The Division of the State Architect has been delegated the authority by the Department of General Services to review and approve the design and oversee and observe the construction of community colleges electing to use the alternative building standards as provided in this section.

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Authority Cited – Education Code Section 81053.

– References Education Code Sections 81052, 81053, and 81130 through 81147.

1.9.2.2.1 Adopting Agency Identification. The provi- sions of this code applicable to buildings identified in this Subsection 1.9.2.2 will be identified in the Matrix Adoption Tables under the acronym DSA-SS/CC.

1.10.0 Department of Health Care Access and Informa- tion/Office of Statewide Hospital Planning and Develop-

ment.

1.10.1 OSHPD 1 and OSHPD 1R. Specific scope of appli- cation of the agency responsible for enforcement, enforce- ment agency, specific authority to adopt and enforce such provisions of this code, unless otherwise stated.

OSHPD 1 and OSHPD 1R

Application – [OSHPD 1] General acute-care hospital buildings. [OSHPD 1R] Non-conforming hospital SPC or freestanding buildings that have been removed from acute care service.

Enforcing Agency – Health Care Access and Informa- tion/Office of Statewide Hospital Planning and Devel- opment (OSHPD). The office shall enforce the Division of the State Architect access compliance regulations and the regulations of the Office of the State Fire Marshal for the above stated facility types.

1.10.1.1 Applicable Administrative Standards:

(1) Title 24, Part 1, California Code of Regulations: Chapters 6 and 7.

(2) Title 24, Part 2, California Code of Regulations: Sections 1.1.0 and 1.10.0, Chapter 1, Division I, and as indicated in the adoption matrix for Chapter 1, Division II.

1.10.1.2 Applicable Building Standards. California Building Standards Code, Title 24, Parts 2, 3, 4, 5, 6, 9, 10 and 11.

– Authority Cited Health and Safety Code Sections 127010, 127015, 1275, and 129850.

– References Health and Safety Code Sections 19958, 127010, 127015, 129680, 1275, and 129675 through 130070.

1.10.1.3 Adopting Agency Identification. The provisions of this code applicable to buildings identified in this Subsection 1.10.1 will be identified in the Matrix Adop- tion Tables under the acronym OSHPD 1, and OSHPD 1R.

1.10.2 OSHPD 2. Specific scope of application of the agency responsible for enforcement, enforcement agency, specific authority to adopt and enforce such provisions of this code, unless otherwise stated.

OSHPD 2

– Application Skilled nursing facilities and intermediate care facility buildings.

Enforcing Agency – Health Care Access and Informa- tion/Office of Statewide Hospital Planning and Devel-

opment (OSHPD). The office shall also enforce the Divi- sion of the State Architect access compliance regulations and the regulations of the Office of the State Fire Marshal for the above stated facility type.

1.10.2.1 Applicable Administrative Standards:

(1) Title 24, Part 1, California Code of Regulations: Chapter 7.

(2) Title 24, Part 2, California Code of Regulations: Sections 1.1.0 and 1.10.0, Chapter 1, Division I, and as indicated in the adoption matrix for Chapter 1, Division II.

1.10.2.2 Applicable Building Standards. California Building Standards Code, Title 24, Parts 2, 3, 4, 5, 6, 9, 10, and 11.

– Authority Cited Health and Safety Code Sections 127010, 127015, 1275, and 129850.

– References Health and Safety Code Sections 127010, 127015, 1275, and 129680.

1.10.2.3 Adopting Agency Identification. The provisions of this code applicable to buildings identified in this Subsection 1.10.2 will be identified in the Matrix Adop- tion Tables under the acronym OSHPD 2.

1.10.3 OSHPD 3. Specific scope of application of the agency responsible for enforcement, enforcement agency, specific authority to adopt and enforce such provisions of this code, unless otherwise stated.

OSHPD 3

– Application Licensed clinics and any freestanding building under a hospital license where outpatient clin- ical services are provided.

– Enforcing Agency Local building department.

1.10.3.1 Applicable Administrative Standards.

(1) Title 24, Part 1, California Code of Regulations: Chapter 7.

(2) Title 24, Part 2, California Code of Regulations: Sections 1.1.0 and 1.10.0, Chapter 1, Division I, and as indicated in the adoption matrix for Chapter 1, Division II.

1.10.3.2 Applicable Building Standards. California Building Standards Code, Title 24, Parts 2, 3, 4, 5, 6, 9, 10, and 11.

– Authority Cited Health and Safety Code Sections 127010, 127015, and 1226.

– References Health and Safety Code Sections 127010, 127015, 129885, and 1226, Government Code Section 54350, and State Constitution Article 11 Section 7.

1.10.3.3 Adopting Agency Identification. The provisions of this code applicable to buildings identified in this Subsection 1.10.3 will be identified in the Matrix Adop- tion Tables under the acronym OSHPD 3.

1.10.4 OSHPD 4. Specific scope of application of the agency responsible for enforcement, enforcement agency, specific

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authority to adopt and enforce such provisions of this code, unless otherwise stated.

OSHPD 4

Application – Correctional Treatment Centers.

– Enforcing Agency Health Care Access and Informa- tion/Office of Statewide Hospital Planning and Devel- opment (OSHPD). The Office shall also enforce the Division of the State Architect access compliance regu- lations and the regulations of the Office of the State Fire Marshal for the above stated facility types.

1.10.4.1 Applicable Administrative Standards:

(1) Title 24, Part 1, California Code of Regulations: Chapter 7.

(2) Title 24, Part 2, California Code of Regulations: Sections 1.1.0 and 1.10.0, Chapter 1, Division I, and as indicated in the adoption matrix for Chapter 1, Division II.

1.10.4.2 Applicable Building Standards. California Building Standards Code, Title 24, Parts 2, 3, 4, 5, 6, 9, 10, and 11.

– Authority Cited Health and Safety Code Sections 127010, 127015, and 129790.

– References Health and Safety Code Sections 127010, 127015, 1275, and 129675 through 130070.

1.10.4.3 Adopting Agency Identification. The provisions of this code applicable to buildings identified in this Subsection 1.10.4 will be identified in the Matrix Adop- tion Tables under the acronym OSHPD 4.

1.10.5 OSHPD 5. Specific scope of application of the agency responsible for enforcement, enforcement agency and the specific authority to adopt and enforce such provisions of this code, unless otherwise stated.

OSHPD 5

Application – Acute psychiatric hospital buildings.

Enforcing Agency – Health Care Access and Informa- tion/Office of Statewide Hospital Planning and Devel- opment (OSHPD). The office shall also enforce the Division of the State Architect – Access Compliance regulations and the regulations of the Office of the State Fire Marshal for the above-stated facility types.

1.10.5.1 Applicable Administrative Standards.

(1) Title 24, Part 1, California Code of Regulations: Chapter 7.

(2) Title 24, Part 2, California Code of Regulations: Sections 1.1.0 and 1.10.0, Chapter 1, Division I, and as indicated in the adoption matrix for Chapter 1, Division II.

1.10.5.2 Applicable Building Standards. California Building Standards Code, Title 24, Parts 2, 3, 4, 5, 6, 9, 10 and 11.

Authority Cited – Health and Safety Code Sections 1275 and 129850.

References – Health and Safety Code Sections 129680, 1275 and 129675 through 130070.

1.10.5.3 Adopting Agency Identification. The provisions of this code applicable to buildings identified in this Subsection 1.10.5 will be identified in the Matrix Adop- tion Tables under the Acronym OSHPD 5.

1.10.6 OSHPD 6. Specific scope of application of the agency responsible for enforcement, enforcement agency and the specific authority to adopt and enforce such provisions of this code, unless otherwise stated.

OSHPD 6

Application – Chemical dependency recovery hospital not within an acute care hospital building or an acute psychiatric facility.

Enforcing Agency – Local building department.

1.10.6.1 Applicable Administrative Standards.

(1) Title 24, Part 1, California Code of Regulations: Chapter 7.

(2) Title 24, Part 2, California Code of Regulations: Section 1.1.0 and 1.10.0, Chapter 1 Division I, and as indicated in the adoption matrix for Chapter I, Division II.

1.10.6.2 Applicable Building Standards. California Building Standards Code, Title 24, Parts 2, 3, 4, 5, 6, 9, 10 and 11.

Authority Cited – Health and Safety Code Sections 1275, 18929 and 129850.

References – Health and Safety Code Sections 1250.3 and 129675-130070.

1.10.6.3 Adopting Agency Identification. The provisions of this code applicable to buildings identified in this Subsection 1.10.6 will be identified in the Matrix Adop- tion Tables under the Acronym OSHPD 6.

1 . 11.0 Office of the State Fire Marshal. 1.11.1 SFM – Office of the State Fire Marshal. Specific scope of application of the agency responsible for enforce- ment, the enforcement agency and the specific authority to adopt and enforce such provisions of this code, unless other- wise stated.

Application:

Institutional, Educational, or any Similar Occupancy. Any building or structure used or intended for use as an asylum, jail, prison, mental hospital, hospital, sanitarium, home for the elderly, children’s nursery, children’s home or institution, school, or any similar occupancy of any capacity.

– Authority Cited Health and Safety Code Section 13143.

– Reference Health and Safety Code Section 13143.

Assembly or Similar Place of Assemblage. Any theater, dancehall, skating rink, auditorium, assembly hall, meeting hall, nightclub, fair building or similar place of assemblage where 50 or more persons may gather together in a building, room or structure for the purpose of amusement, entertain- ment, instruction, deliberation, worship, drinking or dining, awaiting transportation, or education.

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– Authority Cited Health and Safety Code Section 13143.

– Reference Health and Safety Code Section 13143.

Small Family Day Care Homes.

– Authority Cited Health and Safety Code Sections 1597.45, 1597.54, 13143, and 17921.

– Reference Health and Safety Code Section 13143.

Large Family Day Care Homes.

– Authority Cited Health and Safety Code Sections 1597.46, 1597.54, and 17921.

– Reference Health and Safety Code Section 13143.

Residential Facilities and Residential Facilities for the Elderly.

– Authority Cited Health and Safety Code Section 13133.

– Reference Health and Safety Code Section 13143.

Any State Institution or Other State-Owned or Specified State-Occupied Building. Specified State-Occupied Buildings. Any building, structure or area that meets any of the following criteria: (1) A building where the state has contracted into a build-to- suit lease.

(2) A courthouse holding facility or trial court with a deten-

tion area.

(3) A building used by the Department of Corrections and Rehabilitation (CDCR) as a community correctional

reentry center. (4) 100 percent state occupied. (5) State-occupied areas in a state-leased building that is a high-rise and is 75 percent of the net area floor space or more occupied by state entities. (6) State-occupied areas in a building that contains 5,000 square feet (465 m [2] ) or more space of state-leased Group H or Group L occupancy.

(7) A state-leased building with facilities with the primary purpose of housing state records and/or state artifacts of historical significance.

(8) Properties leased by California State University (CSU).

(9) State institutions and their real property.

(10) CAL FIRE occupied areas in leased buildings.

(11) State-leased facilities where the governing body’s fire protection services rely on an all-volunteer fire department.

– Authority Cited Health and Safety Code Sections 13108, 13145, 13146, 16022.5 and 17921.

– Reference Health and Safety Code Sections 13108, 13143, 13145, 13146, 16022.5 and 17921.

High-Rise Structures.

– Authority Cited Health and Safety Code Section 13211.

– Reference Health and Safety Code Section 13143.

Motion Picture Production Studios.

– Authority Cited Health and Safety Code Section 13143.1.

– Reference Health and Safety Code Section 13143.

Organized Camps.

– Authority Cited Health and Safety Code Section 18897.3.

– Reference Health and Safety Code Section 13143.

Residential. All hotels, motels, lodging houses, apartment houses, and dwellings, including congregate residences and buildings and structures accessory thereto. Multiple-story structures existing on January 1, 1975, let for human habita- tion, including and limited to, hotels, motels and apartment houses, less than 75 feet (22 860 mm) above the lowest floor level having building access, wherein rooms used for sleeping are let above the ground floor.

– Authority Cited Health and Safety Code Sections 13143.2 and 17921.

– Reference Health and Safety Code Section 13143.

Residential Care Facilities. Certified family care homes, out- of-home placement facilities, halfway houses, drug and/or alcohol rehabilitation facilities and any building or structure used or intended for use as a home or institution for the housing of any person of any age when such person is referred to or placed within such home or institution for protective social care and supervision services by any governmental agency.

– Authority Cited Health and Safety Code Section 13143.6.

– Reference Health and Safety Code Section 13143.

Tents, Awnings, or other Fabric Enclosures Used in Connec- tion with any Occupancy.

– Authority Cited Health and Safety Code Section 13116.

– Reference Health and Safety Code Section 13143.

Fire Alarm Devices, Equipment, and Systems in Connection with any Occupancy.

– Authority Cited Health and Safety Code Section 13114.

– Reference Health and Safety Code Section 13143.

Hazardous Materials.

– Authority Cited Health and Safety Code Section 13143.9.

– Reference Health and Safety Code Section 13143.

Flammable and Combustible Liquids.

– Authority Cited Health and Safety Code Section 13143.6.

– Reference Health and Safety Code Section 13143.

Public School Automatic Fire Detection, Alarm, and Sprin- kler Systems.

– Authority Cited Health and Safety Code Section 13143 and California Education Code Article 7.5, Sections 17074.50, 17074.52, and 17074.54.

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– References Government Code Section 11152.5, Health and Safety Code Section 13143 and California Education Code Chapter 12.5, Leroy F. Greene School Facilities Act of 1998, Article 1.w.

Wildland-Urban Interface Fire Area.

– Authority Cited Health and Safety Code Sections 13143, 13108.5(a), 18949.2(b), (c) and Government Code Section 51189.

– References Health and Safety Code Sections 13143, Govern- ment Code Sections 51176, 51177, 51178, and 51179 and Public Resources Code Sections 4201 through 4204.

1.11.2 Duties and Powers of the Enforcing Agency.

1.11.2.1 Enforcement. 1.11.2.1.1 The responsibility for enforcement of building standards adopted by the State Fire Marshal and published in the California Building Standards Code relating to fire and panic safety and other regu- lations of the State Fire Marshal shall except as provided in Section 1.11.2.1.2 be as follows: (1) The city, county, or city and county with jurisdic- tion in the area affected by the standard or regu- lation shall delegate the enforcement of the building standards relating to fire and panic safety and other regulations of the State Fire Marshal as they relate to Group R-3 occupancies, as described in Section 310.1 of Part 2 of the California Building Standards Code, to either of the following: 1.1. The chief of the fire authority of the city, county, or city and county, or an authorized representative. 1.2. The chief building official of the city, county, or city and county, or an authorized repre- sentative.

(2) The chief of any city or county fire department or of any fire protection district, and authorized representatives, shall enforce within the jurisdic- tion the building standards and other regulations of the State Fire Marshal, except those described in Item 1 or 4.

(3) The State Fire Marshal shall have authority to enforce the building standards and other regula- tions of the State Fire Marshal in areas outside of corporate cities and districts providing fire protection services.

(4) The State Fire Marshal shall have authority to enforce the building standards and other regula- tions of the State Fire Marshal in corporate cities and districts providing fire protection services on request of the chief fire official or the governing body.

(5) Any fee charged pursuant to the enforcement authority of this section shall not exceed the estimated reasonable cost of providing the service for which the fee is charged pursuant to Section 66014 of the Government Code.

1.11.2.1.2 Pursuant to Health and Safety Code Section 13108, and except as otherwise provided in this section, building standards adopted by the State Fire Marshal published in the California Building Standards Code relating to fire and panic safety shall be enforced by the State Fire Marshal in all state-owned buildings, state-occupied buildings, and state institutions throughout the state. Upon the written request of the chief fire official of any city, county or fire protection district, the State Fire Marshal may authorize such chief fire official and his or her authorized representatives, in their geographical area of responsibility, to make fire prevention inspections of state-owned or state-occu- pied buildings, other than state institutions, for the purpose of enforcing the regulations relating to fire and panic safety adopted by the State Fire Marshal pursuant to this section and building standards relating to fire and panic safety published in the California Building Standards Code. Authorization from the State Fire Marshal shall be limited to those fire departments or fire districts which maintain a fire prevention bureau staffed by paid personnel.

Pursuant to Health and Safety Code Section 13108, any requirement or order made by any chief fire official who is authorized by the State Fire Marshal to make fire prevention inspections of state- owned or state-occupied buildings, other than state institutions, may be appealed to the State Fire Marshal. The State Fire Marshal shall, upon receiving an appeal and subject to the provisions of Chapter 5 (commencing with Section 18945) of Part 2.5 of Division 13 of the Health and Safety Code, determine if the requirement or order made is reasonably consistent with the fire and panic safety regulations adopted by the State Fire Marshal and building standards relating to fire and panic safety published in the California Building Code.

Any person may request a code interpretation from the State Fire Marshal relative to the intent of any regulation or provision adopted by the State Fire Marshal. When the request relates to a specific project, occupancy or building, the State Fire Marshal shall review the issue with the appropriate local enforcing agency prior to rendering such code interpretation. 1.11.2.1.3 Pursuant to Health and Safety Code Section 13112, any person who violates any order, rule or regulation of the State Fire Marshal is guilty of a misdemeanor punishable by a fine of not less than $100.00 or more than $500.00, or by impris- onment for not less than six months, or by both. A person is guilty of a separate offense each day during which he or she commits, continues or permits a violation of any provision of, or any order, rule or regulation of, the State Fire Marshal as contained in this code.

Any inspection authority who, in the exercise of his or her authority as a deputy State Fire Marshal,

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causes any legal complaints to be filed or any arrest to be made shall notify the State Fire Marshal imme- diately following such action. 1.11.2.2 Right of Entry. The fire chief of any city, county, or fire protection district, or such person’s authorized representative, may enter any state institution or any other state-owned or state-occupied building for the purpose of preparing a fire suppression preplanning program or for the purpose of investigating any fire in a state-occupied building. The State Fire Marshal, his or her deputies or salaried assistants, the chief of any city or county fire department or fire protection district and his or her authorized representatives may enter any building or premises not used for dwelling purposes at any reason- able hour for the purpose of enforcing this chapter. The owner, lessee, manager or operator of any such building or premises shall permit the State Fire Marshal, his or her deputies or salaried assistants and the chief of any city or county fire department or fire protection district and his or her authorized representatives to enter and inspect them at the time and for the purpose stated in this section. 1.11.2.3 More Restrictive Fire and Panic Safety Building Standards. 1.11.2.3.1 Any fire protection district organized pursuant to Health and Safety Code Part 2.7 (commencing with Section 13800) of Division 12 may adopt building standards relating to fire and panic safety that are more stringent than those building standards adopted by the State Fire Marshal and contained in the California Building Standards Code. For these purposes, the district board shall be deemed a legislative body and the district shall be deemed a local agency. Any changes or modifications that are more stringent than the requirements published in the California Building Standards Code relating to fire and panic safety shall be subject to Section 1.1.8.1. 1.11.2.3.2 Any fire protection district that proposes to adopt an ordinance pursuant to this section shall, not less than 30 days prior to noticing a proposed ordi- nance for public hearing, provide a copy of that ordi- nance, together with the adopted findings made pursuant to Section 1.11.2.3.1, to the city, county, or city and county where the ordinance will apply. The city, county, or city and county may provide the district with written comments, which shall become part of the fire protection district’s public hearing record. 1.11.2.3.3 The fire protection district shall transmit the adopted ordinance to the city, county, or city and county where the ordinance will apply. The legisla- tive body of the city, county, or city and county may ratify, modify or deny an adopted ordinance and transmit its determination to the district within 15 days of the determination. Any modification or denial of an adopted ordinance shall include a written state- ment describing the reasons for any modifications or denial. No ordinance adopted by the district shall be effective until ratification by the city, county, or city and county where the ordinance will apply. Upon rati-

and_ transmit its determination to the district within 15 days of the determination. Any modification or denial of an adopted ordinance shall include a written state- ment describing the reasons for any modifications or denial. No ordinance adopted by the district shall be effective until ratification by the city, county, or city and county where the ordinance will apply. Upon rati-

fication of an adopted ordinance, the city, county, or city and county shall file a copy of the findings of the district, and any findings of the city, county, or city and county, together with the adopted ordinance expressly marked and identified to which each finding refers, in accordance with Section 1.1.8.1, Item 3.

1.11.2.4 Request for Alternate Means of Protection. Requests for approval to use an alternative material, assembly or materials, equipment, method of construction, method of installation of equipment or means of protec- tion shall be made in writing to the enforcing agency by the owner or the owner’s authorized representative and shall be accompanied by a full statement of the conditions. Sufficient evidence or proof shall be submitted to substan- tiate any claim that may be made regarding its confor- mance. The enforcing agency may require tests and the submission of a test report from an approved testing organization as set forth in Title 19, California Code of Regulation, to substantiate the equivalency of the proposed alternative means of protection.

When a request for alternate means of protection involves hazardous materials, the authority having juris- diction may consider implementation of the findings and recommendations identified in a Risk Management Plan (RMP) developed in accordance with Title 19, Division 2, Chapter 4.5, Article 3.

Approval of a request for use of an alternative mate- rial, assembly of materials, equipment, method of construction, method of installation of equipment, or means of protection made pursuant to these provisions shall be limited to the particular case covered by request and shall not be construed as establishing any precedent for any future request.

1.11.2.5 Appeals. When a request for an alternate means of protection has been denied by the enforcing agency, the applicant may file a written appeal to the State Fire Marshal for consideration of the applicant’s proposal. In considering such appeal, the State Fire Marshal may seek the advice of the State Board of Fire Services. The State Fire Marshal shall, after considering all of the facts presented, including any recommendations of the State Board of Fire Services, determine if the proposal is for the purposes intended, at least equivalent to that specified in these regulations in quality, strength, effectiveness, fire resistance, durability and safety, and shall transmit such findings and any recommendations to the applicant and to the enforcing agency.

1.11.3 Construction Documents.

1.11.3.1 Public Schools. Plans and specifications for the construction, alteration, or addition to any building owned, leased, or rented by any public school district shall be submitted to the Division of the State Architect.

1.11.3.2 Movable Walls and Partitions. Plans or diagrams shall be submitted to the enforcing agency for approval before the installation of, or rearrangement of, any movable wall or partition in any occupancy. Approval shall be granted only if there is no increase in the fire hazard.

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1.11.3.3 New Construction High-Rise Buildings:

(1) Complete plans or specifications, or both, shall be prepared covering all work required to comply with new construction high-rise buildings. Such plans and specifications shall be submitted to the enforcing agency having jurisdiction.

(2) All plans and specifications shall be prepared under the responsible charge of an architect or a civil or structural engineer authorized by law to develop construction plans and specifications, or by both such architect and engineer. Plans and specifications shall be prepared by an engineer duly qualified in that branch of engineering necessary to perform such serv- ices. Administration of the work of construction shall be under the charge of the responsible architect or engineer except that where plans and specifications involve alterations or repairs, such work of construc- tion may be administered by an engineer duly quali- fied to perform such services and holding a valid certificate under Chapter 7 (commencing with Section 65700) of Division 3 of the Business and Professions Code for performance of services in that branch of engineering in which said plans, specifications and estimates and work of construction are applicable.

This section shall not be construed as preventing the design of fire-extinguishing systems by persons holding a C-16 license issued pursuant to Division 3, Chapter 9, Business and Professions Code. In such instances, however, the responsibility charge of this section shall prevail.

1.11.3.4 Existing High-Rise Buildings:

(1) Complete plans or specifications, or both, shall be prepared covering all work required by Section 3412 for existing high-rise buildings. Such plans or specifi- cations shall be submitted to the enforcing agency having jurisdiction.

(2) When new construction is required to conform with the provisions of these regulations, complete plans or specifications, or both, shall be prepared in accor- dance with the provisions of this subsection. As used in this section, “new construction” is not intended to include repairs, replacements or minor alterations which do not disrupt or appreciably add to or affect the structural aspects of the building.

1.11.3.5 Retention of Plans. Refer to Building Standards Law, Health and Safety Code Sections 19850 and 19851 for permanent retention of plans.

1.11.4 Fees.

1.11.4.1 Other Fees. Pursuant to Health and Safety Code Section 13146.2, a city, county, or district which inspects a hotel, motel, lodging house, or apartment house may charge and collect a fee for the inspection from the owner of the structure in an amount, as determined by the city, county or district, sufficient to pay its costs of that inspec- tion.

1.11.4.2 Large Family Day Care. Pursuant to Health and Safety Code Section 1597.46, Large Family Day Care Homes, the local government shall process any required

permit as economically as possible, and fees charged for review shall not exceed the costs of the review and permit

process.

1.11.4.3 High-Rise. Pursuant to Health and Safety Code Section 13217, High-rise Structure Inspection: Fees and costs, a local agency which inspects a high-rise structure pursuant to Health and Safety Code Section 13217 may charge and collect a fee for the inspection from the owner of the high-rise structure in an amount, as determined by the local agency, sufficient to pay its costs of that inspec- tion.

1.11.4.4 Fire Clearance Preinspection. Pursuant to Health and Safety Code Section 13235, Fire Clearance Prein- spection fee, upon receipt of a request from a prospective licensee of a community care facility, as defined in Section 1502, of a residential care facility for the elderly, as defined in Section 1569.2, or of a child day care facility, as defined in Section 1596.750, the local fire enforcing agency, as defined in Section 13244, or State Fire Marshal, whichever has primary jurisdiction, shall conduct a preinspection of the facility prior to the final fire clearance approval. At the time of the preinspection, the primary fire enforcing agency shall price consultation and interpretation of the fire safety regulations and shall notify the prospective licensee of the facility in writing of the specific fire safety regulations which shall be enforced in order to obtain fire clearance approval. A fee equal to, but not exceeding, the actual cost of the preinspection services may be charged for the prein- spection of a facility.

1.11.4.5 Care Facilities. The primary fire enforcing agency shall complete the final fire clearance inspection for a community care facility, residential care facility for the elderly, or child day care facility within 30 days of receipt of the request for the final inspection, or as of the date the prospective facility requests the final prelicensure inspec- tion by the State Department of Social Services, whichever is later.

Pursuant to Health and Safety Code Section 13235, a preinspection fee equal to, but not exceeding, the actual cost of the preinspection services may be charged for the preinspection of a facility.

Pursuant to Health and Safety Code Section 13131.5, a reasonable final inspection fee, not to exceed the actual cost of inspection services necessary to complete a final inspection may be charged for occupancies classified as Residential Care Facilities for the Elderly (RCFE).

Pursuant to Health and Safety Code Section 1569.84, neither the State Fire Marshal nor any local public entity shall charge any fee for enforcing fire inspection regula- tions pursuant to state law or regulation or local ordinance, with respect to Residential Care Facilities for the Elderly (RCFE) which service six or fewer persons.

1.11.4.6 Requests of the Office of the State Fire Marshal. Whenever a local authority having jurisdiction requests that the State Fire Marshal perform plan review and/or inspection services related to a building permit, the appli- cable fees for such shall be payable to the Office of the State Fire Marshal.

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1.11.5 Inspections. Work performed subject to the provisions of this code shall comply with the inspection requirements of Title 24, Part 2, California Building Standards Code, Sections 109.1, 109.3, 109.3.4, 109.3.5, 109.3.6, 109.3.8, 109.3.9, 109.3.10, 109.5, and 109.6 as adopted by the Office of the State Fire Marshal.

1.11.5.1 Existing Group I-1 or R Occupancies. Licensed 24-hour care in a Group I-1 or R occupancy in existence and originally classified under previously adopted state codes shall be reinspected under the appropriate previous code, provided there is no change in the use or character which would place the facility in a different occupancy

group.

1.11.6 Certificate of Occupancy. A Certificate of Occupancy shall be issued as specified in Title 24, Part 2, California Building Code, Section 111.

Exception: Certificates of occupancy are not required for work exempt from permits in accordance with Section 105.2 of the California Building Code.

1.11.7 Temporary Structures and Uses. See Title 24, Part 2, California Building Code, Section 108.

1.11.8 Service Utilities. See Title 24, Part 2, California Building Code, Section 112.

1.11.9 Stop Work Order. See Title 24, Part 2, California Building Code, Section 115.

1.11.10 Unsafe Buildings, Structures, and Equipment. See Title 24, Part 2, California Building Code, Section 116.

1.11.11 Adopting Agency Identification. The provisions of this code applicable to buildings identified in this Section 1.11.0 will be identified in the Matrix Adoption Tables under the acronym SFM.

1.12.0 Reserved for the State Librarian.

1.13.0 Reserved for the Department of Water Resources.

1.14.0 Reserved for the State Lands Commission.

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DIVISION II

SCOPE AND ADMINISTRATION