Scope & Venting Obligations

Grounded in the retrieved California Mechanical Code — click a citation to read the verbatim passage:

• CMC § 2025 Medium relevance — show source text

  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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  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.

  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

• CMC § 802.3 Medium relevance — show source text

  802.3 Minimum Safe Performance. Venting systems shall be designed and constructed to convey all flue and vent gases to the outdoors. [NFPA 54:12.1]

  802.3.1 Appliance Draft Requirements. A venting system shall satisfy the draft requirements of the appliance in accordance with the manufacturer’s instructions. [NFPA 54:12.4.1]

  802.3.2 Appliance Venting Requirements. Appliances required to be vented shall be connected to a vent

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  CHIMNEYS AND VENTS

  ing system designed and installed in accordance with the provisions of Section 802.4 through Section 802.15.

  [NFPA 54:12.4.2]

  802.3.3 Mechanical Draft Systems. Mechanical draft systems shall be listed in accordance with UL 378 and installed in accordance with both the appliance and the mechanical draft system manufacturer’s installation instructions. [NFPA 54:12.4.3.1]

  802.3.3.1 Venting. Appliances requiring venting shall be permitted to be vented by means of mechanical draft systems of either forced or induced draft design. [NFPA 54:12.4.3.2]

  802.3.3.2 Leakage. Forced draft systems and all portions of induced draft systems under positive pressure during operation shall be designed and installed so as to prevent leakage of flue or vent gases into a building. [NFPA 54:12.4.3.3]

  802.3.3.3 Vent Connectors. Vent connectors

  serving appliances vented by natural draft shall not be connected into any portion of mechanical draft systems operating under positive pressure. [NFPA 54:12.4.3.4]

  802.3.3.4 Operation. Where a mechanical draft system is employed, provision shall be made to prevent the flow of gas to the main burners when the draft system is not performing so as to satisfy the operating requirements of the appliance for safe performance. [NFPA 54:12.4.3.5]

  802.3.4 Ventilating Hoods and Exhaust Systems. Where automatically operated appliances, other than food service appliances, are vented through a ventilating hood or exhaust system equipped with a damper or with a power means of exhaust, provisions shall be made to allow the flow of gas to the main burners only when the damper is open to a position to properly vent the appliance and when the power means of exhaust is in operation. [NFPA 54:12.4.4.1]

  802.3.5 Circulating Air Ducts, Above-Ceiling Air- Handling Spaces, and Furnace Plenums. Venting systems shall not extend into or pass through any fabricated air duct or furnace plenum. [NFPA 54:12.4.5.1]

  802.3.6 Above-Ceiling or Nonducted Air Han- dling System. Where a venting system passes through an above-ceiling air space or other nonducted portion of an air-handling system, it shall conform to one of the following requirements:

• CMC § 2025 Medium relevance — show source text

  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.

  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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• CMC § 2025 Medium relevance — show source text

  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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  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.

  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.

• CMC § 701.4 Medium relevance — show source text

  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

  xxxiv

  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

• CMC § 62.1. Medium relevance — show source text

  (3) The mechanical exhaust flow minus the available transfer air from conditioned spaces or return air plenums on the same floor, not in different smoke or fire compartments, and that at their closest point are within 15 feet (4572 mm) of each other. Available transfer air is that portion of outdoor ventilation air that:

  (a) is not required to satisfy other exhaust needs,

  (b) is not required to maintain pressurization of other spaces, and

  (c) is transferable according to applicable codes and standards and to the class of air recirculation limitations in Chapter 4 or ASHRAE 62.1.

  Exceptions: (1) Biosafety level classified laboratories 3 or higher. (2) Vivarium spaces. (3) Spaces that are required by applicable codes and standards to be maintained at positive pressure relative to adjacent spaces. For spaces taking this exception, any transferable air that is not directly transferred shall be made available to the associated air-handling unit and shall be used whenever economizer or other options do not save more energy. (4) Spaces where the demand for transfer air may exceed the available transfer airflow rate and where the spaces have a required negative pressure relationship. For spaces taking this exception, any transferable air that is not directly transferred shall be made available to the associated air-handling unit and shall be used whenever economizer or other options do not save more energy. [ASHRAE 90.1:6.5.7.1] E 503.5.11.2 Kitchen Exhaust Systems. Replacement air introduced directly into the hood cavity of kitchen exhaust hoods shall not exceed 10 percent of the hood exhaust airflow rate. [ASHRAE 90.1:6.5.7.2.1]

  E 503.5.11.2.1 Exhaust Flow Rate. Where a kitchen or dining facility has a total kitchen hood exhaust airflow rate exceeding 5000 ft [3] /min (2.3597 m [3] /s), each hood shall have an exhaust rate in accordance with Table E 503.5.11.2.1.

  Where a single hood, or hood section, is installed over appliances with different duty ratings, the maximum allowable flow rate for the hood or

  hood section shall not exceed the values in Table E 503.5.11.2.1 for the highest appliance duty rating under the hood or hood section. Refer to ASHRAE 154 for definitions of hood type, appliance duty, and net exhaust flow rate. Exception: Seventy-five percent or more of the total replacement air is transfer air that would otherwise be exhausted. [ASHRAE 90.1:6.5.7.2.2] E 503.5.11.2.2 Kitchen or Dining Facility. Where a kitchen or dining facility has a total kitchen hood exhaust airflow rate more than 5000 ft [3] /min (2.3597 m [3] /s), then one of the following shall be provided:

  (1) Fifty percent or more of all replacement air is transfer air that would otherwise be

  exhausted.

  (2) Demand ventilation systems on 75 percent or more of the exhaust air. Such systems shall be capable of and configured to provide 50 percent or more reduction in exhaust and replacement air system airflow rates, including controls necessary to modulate airflow in response to appliance operation and to maintain full capture and containment of smoke, effluent, and combustion products during cooking and idle.

• CMC § 2025 Medium relevance — show source text

  Energy Systems| |16|
  
  Stationary Power Plants| |17|
  
  Geothermal Energy Systems and Ambient Temperature Loops| |18|
  
  Referenced Standards| |Appendix A|
  Residential Plans Examiner Review Form for HVAC System Design| |Appendix B|
  Procedures to be Followed to Place Gas Equipment in Operation| |Appendix C|
  Installation and Testing of Oil (Liquid) Fuel-Fired Equipment| |Appendix D|
  
  Fuel Supply: Manufactured/Mobile Home Parks and Recreational Vehicle
  Parks| |Appendix E|
  Sustainable Practices| |Appendix F|
  
  Sizing of Venting Systems and Outdoor Combustion and Ventilation
  Opening Design| |Appendix G|
  Example Calculation of Outdoor Air Rate| |Appendix H|
  
  Professional Qualifications| |Appendix I|
  
  Indoor Horticultural Facilities| |Appendix J|
  
  Clean Air Delivery| |Useful Tables|Useful Tables|

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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.

  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.

• CMC § 2025 Medium relevance — show source text

  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:

  CHAPTERS	SUBJECTS
  1	Administration
  2	Definitions
  3	General Regulations
  4	Ventilation Air
  5	Exhaust Systems
  6	Duct Systems
  7	Combustion Air
  8	Chimneys and Vents
  9	Installation of Specific Appliances
  10	Boilers and Pressure Vessels
  11	Refrigeration
  12	Hydronics
  13	Fuel Gas Piping
  14	Process Piping
  15	Solar Energy Systems
  16	Stationary Power Plants
  17	Geothermal Energy Systems and Ambient Temperature Loops
  18	Referenced Standards
  Appendix A	Residential Plans Examiner Review Form for HVAC System Design
  Appendix B	Procedures to be Followed to Place Gas Equipment in Operation
  Appendix C	Installation and Testing of Oil (Liquid) Fuel-Fired Equipment
  Appendix D	Fuel Supply: Manufactured/Mobile Home Parks and Recreational Vehicle Parks
  Appendix E	Sustainable Practices
  Appendix F	Sizing of Venting Systems and Outdoor Combustion and Ventilation Opening Design
  Appendix G	Example Calculation of Outdoor Air Rate
  Appendix H	Professional Qualifications
  Appendix I	Indoor Horticultural Facilities
  Appendix J	Clean Air Delivery
  Useful Tables	Useful Tables

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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.

• CMC § 223.0 Medium relevance — show source text

  223.0 – U –

  UMC. [HCD 1, HCD 2, OSHPD 1, 1R, 2, 3, 4, 5 & 6] The most recent edition of Uniform Mechanical Code published by the International Association of Plumbing and Mechanical Officials.

  Unconditioned Space. An area, room, or space not being heated or cooled by any equipment.

  Unit Heater. A heating appliance designed for nonresidential space heating and equipped with an integral means for circulation of air.

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  DEFINITIONS

  Vented Appliance Categories. Category I. An appliance that operates with a nonpositive vent static pressure and with a vent gas temperature that avoids excessive condensate production in the vent.

  [NFPA 54:3.3.4.10.1] Category II. An appliance that operates with a nonpositive vent static pressure and with a vent gas temperature that can cause excessive condensate production in the vent. [NFPA 54:3.3.4.10.2] Category III. An appliance that operates with a positive vent static pressure and with a vent gas temperature that avoids excessive condensate production in the vent.

  [NFPA 54:3.3.4.10.3] Category IV. An appliance that operates with a positive vent static pressure and with a vent gas temperature that can cause excessive condensate production in the vent.

  [NFPA 54:3.3.4.10.4] Vented Decorative Appliance. A vented appliance whose only function is providing an aesthetic effect of flames. Vented Wall Furnace. A self-contained, vented, fuel gasburning appliance complete with grilles or equivalent, designed for incorporation in or permanent attachment to the structure of a building and furnishing heated air, circulated by gravity or by a fan, directly into the space to be heated through openings in the casing. [NFPA 54:3.3.45.7] Ventilating Ceiling. A suspended ceiling containing many small apertures through which air, at low pressure, is forced downward from an overhead plenum dimensioned by the concealed space between the suspended ceiling and the floor or roof above.

  Ventilation System. All of that equipment intended or installed for the purpose of supplying air to or removing air from, any room or space by mechanical means, other than equipment that is a portion of an environmental heating, cooling, absorption, or evaporative cooling system. Venting Collar. The outlet opening of an appliance provided for connection of the vent system. Venting System. The vent or chimney and its connectors, assembled to form a continuous open passageway from an appliance to the outdoors for the purpose of removing products of combustion. This definition also shall include a venting assembly that is an integral part of an appliance. Venting System, Gravity-Type. A system that depends entirely on the heat from the fuel being used to provide the energy required to vent an appliance. Venting System, Power-Type. A system that depends on a mechanical device to provide a positive draft within the venting system. **Volume, Internal Gross.

• CMC § 607.4.1 Medium relevance — show source text

  607.4.1 Design standards. The design, fabrication and assembly of system components shall be suitable for the working pressures, temperatures and structural stresses to be encountered by the components.

  607.4.2 Components in contact with heated oil. System components that come in contact with heated cooking oil shall be rated for the maximum operating temperatures expected in the system.

  607.5 Tank venting. Normal and emergency venting shall be provided for cooking oil storage tanks.

  607.5.1 Normal vents. Normal vents shall be located above the maximum normal liquid line, and shall have a minimum effective area not smaller than the largest filling or withdrawal connection. Normal vents shall be permitted to vent inside the building.

  607.5.2 Emergency vents. Emergency relief vents shall be located above the maximum normal liquid line, and shall be in the form of a device or devices that will relieve excessive internal pressure caused by an exposure fire. For nonmetallic tanks, the emergency relief vent shall be allowed to be in the form of construction. Emergency vents shall be permitted to vent inside the building.

  607.6 Heating of cooking oil. Electrical equipment used for heating cooking oil in cooking oil storage systems shall be listed to UL 499 and shall comply with the California Electrical Code . Use of electrical immersion heaters shall be prohibited in nonmetallic tanks.

  607.7 Electrical equipment. Electrical equipment used for the operation of cooking oil storage systems shall comply with the Cali- fornia Electrical Code.

  SECTION 608—MECHANICAL REFRIGERATION

  [M] 608.1 Scope. Refrigeration systems shall be installed in accordance with the California Mechanical Code .

  608.1.1 Refrigerants other than ammonia. Where a refrigerant other than ammonia is used, refrigeration systems and the buildings in which such systems are installed shall be in accordance with ASHRAE 15.

  608.1.2 Ammonia refrigeration. Refrigeration systems using ammonia refrigerant and the buildings in which such systems are installed shall comply with IIAR 2 for system design; IIAR 6 for inspection, testing and maintenance; and IIAR 7 for operating procedures. Decommissioning of ammonia refrigeration systems shall comply with IIAR 8, and engineering practices for existing ammonia refrigeration systems shall be in accordance with IIAR 9.

  608.2 Permits. An operational permit shall be obtained for refrigeration systems as set forth in Section 105.5.46.

  [M] 608.3 Refrigerants. The use and purity of new, recovered and reclaimed refrigerants shall be in accordance with the California Mechanical Code .

  [M] 608.4 Refrigerant classification. Refrigerants shall be classified in accordance with the California Mechanical Code .

  [M] 608.5 Change in refrigerant type. A change in the type of refrigerant in a refrigeration system shall be in accordance with the California Mechanical Code .

  608.6 Access. Access to refrigeration systems having a refrigerant circuit containing more than 220 pounds (100 kg) of Group A1 or 30 pounds (14 kg) of any other group refrigerant shall be provided for the fire department at all times as required by the fire code official.

• CMC § 509.3.3.1 Medium relevance — show source text

  WATER HEATERS

  509.3.3.1 Venting. Appliances requiring venting shall be permitted to be vented by means of mechanical draft systems of either forced or induced draft design. [NFPA 54:12.4.3.2]

  509.3.3.2 Leakage. Forced draft systems and all portions of induced draft systems under positive pressure during operation shall be designed and installed so as to prevent leakage of flue or vent gases into a building. [NFPA 54:12.4.3.3]

  509.3.3.3 Vent Connectors. Vent connectors serving appliances vented by natural draft shall not be connected into any portion of mechanical draft systems operating under positive pressure. [NFPA 54:12.4.3.4]

  509.3.3.4 Operation. Where a mechanical draft system is employed, provision shall be made to prevent the flow of gas to the main burners when the draft system is not performing so as to satisfy the operating requirements of the appliance for safe performance. [NFPA 54:12.4.3.5]

  509.3.4 Ventilating Hoods and Exhaust Systems. Where automatically operated appliances, other than food service appliances, are vented through a ventilating hood or exhaust system equipped with a damper or with a power means of exhaust, provisions shall be made to allow the flow of gas to the main burners only when the damper is open to a position to properly vent the appliance and when the power means of exhaust is in operation. [NFPA 54:12.4.4.1]

  509.3.5 Circulating Air Ducts, Above-Ceiling Air- Handling Spaces, and Furnace Plenums. Venting systems shall not extend into or pass through any fabricated air duct or furnace plenum. [NFPA 54:12.4.5.1] 509.3.6 Above-Ceiling or Nonducted Air Han- dling System. Where a venting system passes through an above-ceiling air space or other nonducted portion of an air-handling system, it shall conform to one of the following requirements:

  (1) The venting system shall be a listed special gas vent, other system serving a Category III or Category IV appliance, or other positive pressure vent, with joints sealed in accordance with the appliance or vent manufacturer’s instructions.

  (2) The vent system shall be installed such that no fittings or joints between sections are installed in the above-ceiling space.

  (3) The venting system shall be installed in a conduit or enclosure with joints between the interior of the enclosure and the ceiling space sealed. [NFPA 54:12.4.5.2]

  509.4 Type of Venting System to be Used. The type of venting system to be used shall be in accordance with Table 509.4. [NFPA 54:12.5.1]

  509.4.1 Plastic Piping. Where plastic piping is used to vent an appliance, the appliance shall be listed for use with such venting materials and the appliance manufac

  turer’s installation instructions shall identify the specific plastic piping material. The plastic pipe venting materials shall be labeled in accordance with the product standards specified by the appliance manufacturer or shall be listed and labeled in accordance with UL 1738. [NFPA 54:12.5.2]

  TABLE 509.4

• CMC § 11B-8 Medium relevance — show source text

  DIVISION 2 – SCOPING REQUIREMENTS . . . . . . . . . . . . . . . .11B-8

  11B-201 Application. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11B-8

  11B-202 Existing Buildings and Facilities . . . . . . . . . . . . . . . . . . 11B-8

  11B-203 General Exceptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11B-10

  11B-204 Protruding Objects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11B-11

  11B-205 Operable Parts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11B-11

  11B-206 Accessible Routes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11B-12

  11B-207 Accessible Means of Egress. . . . . . . . . . . . . . . . . . . . . . 11B-16

  11B-208 Parking Spaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11B-16

  11B-209 Passenger Drop-off and Loading Zones and Bus Stops . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11B-18

  11B-210 Stairways . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11B-18

  11B-211 Drinking Fountains and Bottle-Filling Stations . . . 11B-18

  11B-212 Kitchens, Kitchenettes, Wet Bars and Sinks . . . . . . 11B-19

  11B-213 Toilet Facilities and Bathing Facilities . . . . . . . . . . . 11B-19

  11B-214 Washing Machines and Clothes Dryers. . . . . . . . . . . 11B-20

  11B-215 Fire Alarm Systems and Carbon Monoxide Alarm Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11B-20

  11B-216 Signs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11B-20

  11B-217 Telephones . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11B-22