CMC · California Mechanical Code
Scope, applicability and use of Chapter 2 definitions
Chapter 2 contains the code’s definitions (see §201.1 and §202.1) and must be consulted to determine the technical meanings that control code application and enforcement.
Last reviewed: July 6, 2026
Overview
Chapter 2 of the California Mechanical Code is the repository of terms used throughout the CMC and is intended to give precise meanings to words that affect how requirements are applied and enforced. The chapter establishes that, for the purposes of the code, defined terms in this chapter take the meanings indicated (see §201.1) and that definitions are arranged and used to promote consistent interpretation across the code . To maintain consistency and a common technical vocabulary, Chapter 2 explains when ordinary dictionary meanings apply and when a specific code definition controls .
Key sections to consult are the chapter heading and scope language (201.0 / §201.1) and the definitions arrangement (202.0 / §202.1), which indicate applicability and how terms are organized and used in the CMC . Because Chapter 2 can alter the meaning of provisions in other chapters, readers should consult these sections at the start of code interpretation, plan review, or enforcement actions to confirm which technical sense of a term applies.
In this section
Code references
Grounded in the retrieved California Mechanical Code — click a citation to read the verbatim passage:
CMC § 2025 High 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|2025 CALIFORNIA MECHANICAL CODE xiii
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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.
California Mechanical Code Medium relevance — show source text
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. 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.
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, lo
CFC § 1203 Medium relevance — show source text
CHAPTER TOPICS Col2 PARTS AND CHAPTERS SUBJECTS Part I—Chapters 1 and 2 Administrative and definitions Part II—Chapters 3 and 4 General safety provisions Part III—Chapters 5 through 12 Building and equipment design features Part III—Chapters 13 through 19 Reserved for future use Part IV—Chapters 20 through 41_; 48 and 49_ Special occupancies and operations Part IV—Chapters 42 through_47_ Reserved for future use Part V—Chapters 50, 51 and 53 through 67 Hazardous materials Part V—Chapters_ 52,_ 68 through 79 Reserved for future use Part VI—Chapter 80 Referenced standards Part VII—Appendices A through Q Adoptable and informational appendices 2025 CALIFORNIA FIRE CODE xiii
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California Building Code Correlated Topics
The CFC requirements for fire-resistance-rated construction, interior finish, fire protection systems, means of egress and construction safeguards are directly correlated to the chapters containing parallel requirements in the CBC as follows:
CFC/CBC CORRELATED TOPICS Col2 Col3 CFC CHAPTER/SECTION CBC CHAPTER/SECTION SUBJECT Chapter 7 Chapter 7 Fire and smoke protection features (Fire-resistance-rated construction in the CBC) Chapter 8 Chapter 8 Interior finish, decorative materials and furnishings Chapter 9 Chapter 9 Fire protection and life safety systems Chapter 10 Chapter 10 Means of egress Section 1203 Chapter 27 Emergency and standby power Chapter 31 Section 3103 Temporary structures Chapter 33 Chapter 33 Construction fire safety Chapters 50–67 Sections 307, 414, 415 Hazardous materials and Group H requirements PART I—ADMINISTRATIVE
Chapter 1 Scope and Administration.
Chapter 1 establishes the limits of applicability of the code and describes how the code is to be applied and enforced. The provisions of Chapter 1 establish the authority and duties of the code official appointed by the authority having jurisdiction and also establish the rights and privileges of the design professional, contractor and property owner.
Chapter 2 Definitions.
Chapter 2 is the repository of the definitions of terms used in the body of the code. The user of the code should be familiar with and consult this chapter because the definitions are essential to the correct interpretation of the code and because the user may not be aware that a term is defined.
PART II—GENERAL SAFETY PROVISIONS
Chapter 3 General Requirements
General regulations contained in Chapter 3, are intended to improve premises safety for everyone, including construction workers, tenants, operations and maintenance personnel, and emergency response personnel.
Chapter 4 Emergency Planning and Preparedness
Chapter 4 addresses the human contribution to life safety during emergencies. Continuous training and scheduled fire, evacuation and lockdown drills can be as important as the required periodic inspections and maintenance of built-in fire protection features. The level of preparation by the occupants also improves the emergency responders’ abilities during an emergency.
PART III—BUILDING AND EQUIPMENT DESIGN FEATURES
Chapter 5 Fire Service Features
CMC § 1-4 Medium relevance — show source text
1.11 Office of the State Fire Marshal . . . . . . . . . . . . . . . . . . . 1-4
1.12 Board of Forestry. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-10
DIVISION II SCOPE AND ADMINISTRATION . . . . . . . . . . . . . 1-15
PART 1—GENERAL PROVISIONS. . . . . . . . . . . . . . . . . . . . . . . . . . 1-15
101 Scope and General Requirements. . . . . . . . . . . . . . 1-15
102 Applicability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-16
PART 2—ADMINISTRATION AND ENFORCEMENT . . . . . . . . . . . 1-17
103 Code Compliance Agency . . . . . . . . . . . . . . . . . . . . . 1-17
104 Duties and Powers of the Code Official . . . . . . . . . 1-17
105 Permits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-19
106 Construction Documents . . . . . . . . . . . . . . . . . . . . . 1-20
107 Temporary Uses, Equipment and Systems . . . . . . 1-21
108 Fees . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-21
109 Inspection and Enforcement . . . . . . . . . . . . . . . . . . 1-22
110 Certificate of Completion . . . . . . . . . . . . . . . . . . . . . 1-24
111 Service Utilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-24
112 Means of Appeals. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-24
113 Stop Work Order . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-25
CHAPTER 2 DEFINITIONS . . . . . . . . . . . . . . . . . . . . . . . . . 2-3
201 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-3
202 Definitions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-3
CHAPTER 3 WILDLAND-URBAN INTERFACE AREAS . . . . 3-3
CMC § 508.5 Medium relevance — show source text
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defined in Section 508.5) and small bed and breakfast-style hotels where there are five or fewer guestrooms and the hotel is owneroccupied. The IBC applies to all types of buildings and structures unless exempted. Work exempted from permits is listed in Section 105.2.
ARRANGEMENT AND FORMAT OF THE 2025 CBC
The format of the CBC allows each chapter to be devoted to a particular subject. The following table shows how the CBC is divided. The subsequent tables show CBC requirements that are correlated with other Codes. The chapter synopses detail the scope and intent of the provisions of the CBC.
CHAPTER TOPICS Col2 CHAPTERS SUBJECTS 1, 2 Administration and Definitions 3 Use and Occupancy Classifications 4, 31,_ 31A–31F_ Special Requirements for Specific Occupancies or Elements 5–6 Height and Area Limitations Based on Type of Construction 7–9 Fire Resistance and Protection Requirements 10 Requirements for Evacuation 11A, 11B Specific Requirements to Allow Use and Access to a Building for Persons with Disabilities 12, 27,_28,_30 Building Systems, Such as Lighting, HVAC, Elevators 13 This chapter is not adopted in California. Refer to California Energy Code, Title 24, Part 6. 14–26 Structural Components—Performance and Stability 32 Encroachment Outside of Property Lines 33 Safeguards during Construction 35 Referenced Standards Appendices A–Q Appendices INTERNATIONAL FIRE CODE CORRELATED TOPICS
The IBC requirements for hazardous materials, fire-resistance-rated construction, interior finish, fire protection systems, means of egress, emergency and standby power, and temporary structures are directly correlated with the requirements of the International Fire Code ® (IFC®). The following table shows chapters/sections of the IBC that are correlated with the IFC:
IBC/IFC CORRELATED TOPICS Col2 Col3 IBC CHAPTER/SECTION IFC CHAPTER/SECTION SUBJECT Sections 307, 414, 415 Chapters 50–67 Hazardous materials and Group H requirements Chapter 7 Chapter 7 Fire-resistance-rated construction (fire and smoke protection features in the IFC) Chapter 8 Chapter 8 Interior finish, decorative materials and furnishings Chapter 9 Chapter 9 Fire protection systems Chapter 10 Chapter 10 Means of egress Chapter 27 Section 604 Standby and emergency power Section 3103 Chapter 31 Temporary structures Chapter 1 Scope and Administration.
Chapter 1 establishes the limits of applicability of the code and describes how the code is to be applied and enforced. The provisions of Chapter 1 establish the authority and duties of the code official appointed by the authority having jurisdiction and also establish the rights and privileges of the design professional, contractor and property owner.
Chapter 2 Definitions.
Chapter 2 is the repository of the definitions of terms used in the body of the code. The user of the code should be familiar with and consult this chapter because the definitions are essential to the correct interpretation of the code and because the user may not be aware that a term is defined.
CRC § 2025 Medium relevance — show source text
It is important to understand that the IRC contains coverage for what is conventional and common in residential construction practice. While the IRC will provide all of the needed coverage for most residential construction, it might not address construction practices and systems that are atypical or rarely encountered in the industry. Therefore, the IRC contains several references to other codes either as an alternative to the provisions of the IRC or where the IRC lacks coverage for a particular type of structure, design, system, appliance or method of construction. In other words, the IRC is meant to be all inclusive for typical residential construction and it relies on other codes only where alternatives are desired or where the code lacks coverage for the uncommon aspect of residential construction. Of course, the IRC constantly evolves to address new technologies and construction practices that were once uncommon, but are now common.
The IRC is unique in that much of it, including Chapters 3 through 9 and Chapters 34 through 43, is presented in an ordered format that is consistent with the normal progression of construction, starting with the design phase and continuing through the final trimout phase. This is consistent with the “cookbook” philosophy of the IRC.
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Arrangement and Format of the 2025 CRC
The CRC is divided into nine main parts, specifically: Part I—Administrative, Part II—Definitions, Part III—Building Planning and Construction, Part IV—Energy Conservation, Part V—Mechanical, Part VI—Fuel Gas, Part VII—Plumbing, Part VIII—Electrical and Part IX—Referenced Standards. Parts IV through VIII of IRC are not adopted in California and replaced with references to appropriate parts of Title 24. The following provides a brief description of the content of each chapter and appendix of the CRC:
Chapter 1 Scope and Administration.
Chapter 1 establishes the limits of applicability of the code and describes how the code is to be applied and enforced. The provisions of Chapter 1 establish the authority and duties of the code official appointed by the authority having jurisdiction and also establish the rights and privileges of the design professional, contractor and property owner.
Chapter 2 Definitions.
Chapter 2 is the repository of the definitions of terms used in the body of the code. The user of the code should be familiar with and consult this chapter because the definitions are essential to the correct interpretation of the code and because the user may not be aware that a term is defined.
Chapter 3 Building Planning.
Chapter 3 provides guidelines for a minimum level of structural integrity, life safety, fire safety and livability for inhabitants of dwelling units regulated by this code. Chapter 3 is a compilation of the code requirements specific to the building planning sector of the design and construction process. This chapter sets forth code requirements dealing with light, ventilation, sanitation, minimum room size, ceiling height and environmental comfort. Chapter 3 establishes life-safety provisions including limitations on glazing used in hazardous areas, specifications on stairways, use of guards at elevated surfaces, window and fall protection, and rules for means of egress. Snow, wind and seismic design live and dead loads and flood-resistant construction, as well as solar energy systems are addressed in this chapter.
Chapter 4 Foundations.
CMC § 1-24 Medium relevance — show source text
102 Applicability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-24
Part 2—Administration and Enforcement . . . . . . . . . . . . . . . . . 1-24
103 Code Compliance Agency . . . . . . . . . . . . . . . . . . . . . . 1-24
104 Duties and Powers of Building Official. . . . . . . . . . . 1-25
105 Permits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-27
106 Floor and Roof Design Loads . . . . . . . . . . . . . . . . . . . 1-29
107 Construction Documents . . . . . . . . . . . . . . . . . . . . . . 1-29
108 Temporary Structures, Equipment and Systems . . . . . . . . . . . . . . . . . . . . . 1-31
109 Fees . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-31
110 Inspections. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-31
111 Certificate of Occupancy. . . . . . . . . . . . . . . . . . . . . . . 1-33
112 Service Utilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-33
113 Means of Appeals. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-33
114 Violations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-34
115 Stop Work Order . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-34
CHAPTER 2 DEFINITIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . .2-1
201 General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-11
202 Definitions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-11
CHAPTER 3 OCCUPANCY CLASSIFICATION AND USE . . . . .3-1
301 Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3
302 Occupancy Classification and Use Designation . . . . 3-3
CMC § 204.0 Medium relevance — show source text
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204.0
206.0
207.0
208.0
209.0
210.0
214.0
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216.0
217.0
222.0
223.0
228.0
|||X|X|X|||||X|X|X|X|X|X|X||||||||| |Adopting Agency
Adopt Entire Chapter
Adopt Entire Chapter as
amended (amended sections
listed below)
Adopt only those sections
that are listed below
Chapter/Section
203.0
204.0
206.0
207.0
208.0
209.0
210.0
214.0
215.0
216.0
217.0
222.0
223.0
228.0
||||||||||X||X|X|X|X||||||||||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 2
DEFINITIONS
201.0 General.
201.1 Applicability. For the purpose of this code, the following terms have the meanings indicated in this chapter.
No attempt is made to define ordinary words, which are used in accordance with their established dictionary meanings, except where a word has been used loosely, and it is necessary to define its meaning as used in this code to avoid misunderstanding.
202.0 Definition of Terms.
202.1 General. The definitions of terms are arranged alphabetically according to the first word of the term.
203.0 – A –
Absorption Unit. An absorption refrigeration system that has been factory-assembled and tested prior to its installation.
Accepted Engineering Practice. That which conforms to technical or scientific-based principles, test, or standards that are accepted by the engineering profession.
Access Panel. A closure device used to cover an opening into a duct, an enclosure, equipment, or an appurtenance.
[NFPA 96:3.3.1]
Accessible. Where applied to a device, appliance, or equipment, “accessible” means having access thereto, but which first may require the removal of an access panel, door, or similar obstruction.
Accessible, Readily. Having a direct access without the necessity of removing a panel, door, or similar obstruction.
CMC § 5701.3 Medium relevance — show source text
Storage and use of fuel oil in tanks and containers connected to oil-burning equipment. Such storage and use shall be in accordance with Section 605. For abandonment of fuel oil tanks, this chapter applies.
Refrigeration systems (see Section 608).
Storage and display of aerosol products complying with Chapter 51.
Storage and use of liquids that do not have a fire point when tested in accordance with ASTM D92.
Liquids with a flash point greater than 95°F (35°C) in a water-miscible solution or dispersion with a water and inert (noncombustible) solids content of more than 80 percent by weight, which do not sustain combustion.
Liquids without flash points that can be flammable under some conditions, such as certain halogenated hydrocarbons and mixtures containing halogenated hydrocarbons.
The storage of beer, distilled spirits and wines in barrels and casks.
Commercial cooking oil storage tank systems located within a building and designed and installed in accordance with Section 607 and NFPA 30.
Application and release of pesticide and agricultural products and materials intended for use in weed abatement, erosion control, soil amendment or similar applications where applied in accordance with the manufacturer’s instructions and label directions.
The off-site transportation of flammable or combustible liquids where in accordance with Department of Transportation (DOTn) regulation.
5701.3 Referenced documents. The applicable requirements of Chapter 50, other chapters of this code, the California Building Code and the California Mechanical Code pertaining to flammable liquids shall apply.
5701.4 Permits. Permits shall be required as set forth in Sections 105.5 and 105.6.
5701.5 Material classification. Flammable and combustible liquids shall be classified in accordance with the definitions in Chapter 2.
When mixed with lower flash-point liquids, Class II or III liquids are capable of assuming the characteristics of the lower flash-point liquids. Under such conditions, the appropriate provisions of this chapter for the actual flash point of the mixed liquid shall apply.
When heated above their flash points, Class II and III liquids assume the characteristics of Class I liquids. Under such conditions, the appropriate provisions of this chapter for flammable liquids shall apply.
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FLAMMABLE AND COMBUSTIBLE LIQUIDS
SECTION 5702—DEFINITIONS
5702.1 Definitions. The following terms are defined in Chapter 2:
ALCOHOL-BASED HAND RUB.
BULK PLANT OR TERMINAL.
BULK TRANSFER.
COMBUSTIBLE LIQUID.
Class II.
Class IIIA.
Class IIIB.
FIRE POINT.
FLAMMABLE LIQUID.
Class IA.
Class IB.
Class IC.
FLASH POINT.
FUEL LIMIT SWITCH.
LIQUID STORAGE ROOM.
LIQUID STORAGE WAREHOUSE.
MOBILE FUELING.
PROCESS TRANSFER.
REFINERY.
REMOTE EMERGENCY SHUTOFF DEVICE.
REMOTE SOLVENT RESERVOIR.
SOLVENT DISTILLATION UNIT.
TANK, PRIMARY.
TANK IN AN UNDERGROUND AREA.
SECTION 5703—GENERAL REQUIREMENTS
CMC § 1.11.0. Medium relevance — show source text
(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.)
Adopting Agency BSC BSC-
CGSFM HCD Col6 Col7 DSA Col9 Col10 OSHPD Col12 Col13 Col14 Col15 Col16 Col17 BSCC DPH AGR DWR CEC CA SL SLC Adopting Agency BSC BSC-
CGSFM 1 2 1-AC AC ** SS** ** SS/CC** 1 1R 2 3 4 5 6 6 6 6 6 6 6 6 6 Adopt Entire Chapter X X X X X X X X X X X X Adopt Entire Chapter as
amended (amended sections
listed below)Adopt only those sections
that are listed belowChapter/Section 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 13
FUEL GAS PIPING
1301.0 Scope of Gas Piping.
1301.1 Applicability. The regulations of this chapter shall govern the installation of fuel gas piping in or in connection with a building, structure or within the property lines of premises up to 5 pounds-force per square inch (psi) (34 kPa) for natural gas and 10 psi (69 kPa) for undiluted propane, other than service pipe.
1302.0 Coverage of Piping System.
CMC § 17995.5 Medium relevance — show source text
References – Business and Professions Code Division 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. California Code of Regulations, Title 20, Sections 1605.1, 1605.3 and 1607.
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DIVISION I CALIFORNIA ADMINISTRATION
1.8.2.1.2 Housing Accessibility.
Application – Covered multifamily dwellings as defined in Chapter 2 of the California Code of Reg- ulations, Title 24, Part 2, also known as the Cali- fornia Building Code including but not limited to lodging houses, dormitories, timeshares, condo- miniums, shelters for homeless persons, congregate residences, apartments, dwellings, employee hous- ing, 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 abbrevi- ation “HCD 1-AC” require specific accommoda- tions for persons with disabilities, as defined in Chapter 2 of the California Building Code. The application of such provisions shall be in conjunc- tion 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:
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 exist- ing covered multifamily dwellings.
3. Additions to existing buildings, where the addi- tion alone meets the definition of covered mul- tifamily 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.
CMC § 2-3 Medium relevance — show source text
VACUUM||||X|||||||||||||||||||| |REPAIR||||X|||||||||||||||||||| |REROOFING||||X|||||||||||||||||||| |RESIDENTIAL CARE FACILITY FOR THE
CHRONICALLY ILL (RCF/CI)|||X||||||||||||||||||||| |RESIDENTIAL CARE FACILITY FOR THE
ELDERLY (RCFE)|||X||||||||||||||||||||| |RESIDENTIAL FACILITY (RF)|||X||||||||||||||||||||| |RESTRAINT|||X||||||||||||||||||||| |ROOF ASSEMBLY||||X|||||||||||||||||||| |ROOF RECOVER||||X|||||||||||||||||||| |ROOF REPAIR||||X|||||||||||||||||||| |ROOF REPLACEMENT||||X|||||||||||||||||||| |SKYLIGHTS AND SLOPED GLAZING||||X|||||||||||||||||||| |SLEEPING UNIT||||X|||||||||||||||||||| |STATE-OWNED/LEASED BUILDING|||X||||||||||||||||||||| |SUBSTANTIAL IMPROVEMENT||||X|||||||||||||||||||| |SUNROOM||||X|||||||||||||||||||| |TERMINALLY ILL|||X||||||||||||||||||||| |TESTING AGENCY||||X|||||||||||||||||||| |THIRD-PARTY CERTIFICATION
AGENCY||||X|||||||||||||||||||| |THIRD-PARTY CERTIFIED||||X|||||||||||||||||||| |TODDLER|||X||||||||||||||||||||| |VENT||||X|||||||||||||||||||| |VENT CONNECTOR||||X|||||||||||||||||||| |VENT SYSTEM||||X|||||||||||||||||||| |VENTILATION||||X|||||||||||||||||||| |WATER HEATER||||X|||||||||||||||||||| |WHOLE-HOUSE MECHANICAL
VENTILATION SYSTEM||||X|||||||||||||||||||| |WILDLAND-URBAN INTERFACE (WUI)|||X|||||||||||||||||||||The state agency does not adopt sections identified with the following symbol: †
2025 CALIFORNIA RESIDENTIAL CODE 2-3
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
2-4 2025 CALIFORNIA RESIDENTIAL CODE
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
Part II—Definitions
2 DEFINITIONS
User notes:
About this chapter: Codes, by their very nature, are technical documents. Every word, term and punctuation mark can add to or change the meaning of a technical requirement. It is necessary to maintain a consensus on the specific meaning of each term contained in the code. Chapter 2 performs this function by stating clearly what specific terms mean for the purpose of the code.
ICC code development note: Code change proposals to definitions in this chapter preceded by a bracketed letter are considered by the IRC—Building Code Development Committee [RB], the IRC—Mechanical/Plumbing Code Development Committee [MP] or the IECC—Residential Code Development Committee [RE] during the Group B (2025) Code Development Cycle.
SECTION R201—GENERAL
R201.1 Scope. Unless otherwise expressly stated, the following words and terms shall, for the purposes of this code, have the meanings indicated in this chapter.
Frequently asked questions
What does §201.1 say about applicability?
Section 201.1 states that, for the purposes of the code, the terms in Chapter 2 have the meanings indicated in that chapter — i.e., those definitions govern interpretation unless another provision expressly states otherwise .
How are definitions organized and when should I consult them?
Definitions are arranged alphabetically (see §202.1) and should be consulted whenever a code term could affect compliance, design, enforcement, or when a word’s ordinary meaning might differ from its technical use in the CMC .
What if a term isn’t defined in Chapter 2?
If a term is not defined in Chapter 2, the code directs the user to rely on the ordinarily accepted (dictionary) meaning unless another code cross-reference or provision gives a specific definition .
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