CMC · California Mechanical Code

General Regulations

Chapter 3 establishes the CMC’s cross‑cutting applicability, approval, safety, access, and coordination requirements for mechanical equipment.

Last reviewed: July 6, 2026

Overview

Chapter 3 of the California Mechanical Code (CMC) contains the cross‑cutting requirements that apply to heating, ventilating, air‑conditioning, refrigeration, miscellaneous heat‑producing, and energy‑utilizing equipment and appliances. It establishes applicability, approval and listing, installation and access requirements, condensate and clearance rules, and other system‑level safety provisions that apply wherever mechanical equipment is installed (§301.1, §301.2).

This chapter matters because it sets the baseline safety, access, and coordination rules used by many later chapters — it is intentionally general so those specific chapters can reference these foundational requirements (see the Chapter 3 summary and the list of topics covered). The chapter also points users to referenced standards (see Chapter 18) and includes specific subsections on matters such as equipment approval and electrical connections (§301.2, §301.4).

Because Chapter 3 is adopted and applied across multiple state agencies and building applications, review the chapter text and the adoption/matrix tables to confirm which sections apply to a given project or enforcing agency.

In this section

Code references

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

  • CMC § 1.11.0. High relevance — show source text

    5_||||||||||X|X|X||X|X|||||||||| |321.0||||||||||X||X|X|X|X|||||||||| |322.0
    ||||||||||X||X|X|X|X|||||||||| |323.0
    ||||||||||X|X|X||X|X|||||||||| |324.0||||||||||X|X|X|X|X|X|||||||||| |325.0||||||||||||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 3

    GENERAL REGULATIONS

    301.0 General.

    301.1 Applicability. This chapter covers general requirements for heating, ventilating, air-conditioning, refrigeration, miscellaneous heat-producing, and energy-utilizing equipment or appliances. Such equipment or appliances shall comply with the requirements of this code.

    301.2 Approval. Equipment or appliance shall be approved by the Authority Having Jurisdiction for safe use or comply with applicable nationally recognized standards as evidenced by the listing and label of an approved agency. A list of accepted standards is included in Chapter 18. Defective materials or parts shall be replaced in such a manner as not to invalidate an approval.

    301.3 Design of Equipment. The installer or contractor shall furnish satisfactory evidence that the appliance is constructed in accordance with the requirements of this code. The permanently attached label of an approved agency shall be permitted to be accepted as such evidence. 301.4 Electrical Connections. For equipment regulated by this code:

    (1) Equipment requiring electrical connections of more than 50 volts shall have a positive means of disconnect adjacent to and in sight from the equipment served.

    Exception: Other power disconnect means shall be acceptable where in accordance with the California Elec- trical Code .

    (2) A 120 volt receptacle shall be located within 25 feet (7620 mm) of the equipment for service and maintenance purposes. The receptacle outlet shall be on the supply side of the disconnect switch. The receptacle need not be located on the same level as the equipment.

    (3) Electrical wiring, controls, and connections to equipment and appliances regulated by this code shall be in accordance with the California Electrical Code . 301.5 Oil-Burning Appliances. The tank, piping, and valves for appliances burning oil shall be installed in accordance with the requirements of NFPA 31.

  • 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|

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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 § 303.7 Medium relevance — show source text

    2||||||||||†|†|†|†|†|†|||||||||| |303.7|||X|||||||||||||||||||||| |303.7.1||||X|X|||||||||||||||||||| |305.2_Exception_||||X|X|||||||||||||||||||| |306.2
    ||||||||||X||||||||||||||| |311.5
    |||||||||||||||||||||X|||| |316.2||||X|X|||||||||||||||||||| |316.5||||X|X|||||||||||||||||||| |316.9||||X|X|||||||||||||||||||| |318.0||||||||||X|X|X|X|X|X|||||||||| |319.1||||||||||X|X|||X|X|||||||||| |319.2||||||||||||X||X||||||||||| |320.1||||||||||X|X|||X|X|||||||||| |320.2||||||||||||X||X||||||||||| |320.3|||||||||||||X|||||||||||| |320.4||||||||||X||||X||||||||||| |320.5||||||||||X|X|X||X|X|||||||||| |321.0||||||||||X||X|X|X|X|||||||||| |322.0
    ||||||||||X||X|X|X|X|||||||||| |323.0
    ||||||||||X|X|X||X|X|||||||||| |324.0||||||||||X|X|X|X|X|X|||||||||| |325.0||||||||||||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 3

    GENERAL REGULATIONS

    301.0 General.

    301.1 Applicability. This chapter covers general requirements for heating, ventilating, air-conditioning, refrigeration, miscellaneous heat-producing, and energy-utilizing equipment or appliances. Such equipment or appliances shall comply with the requirements of this code.

  • CMC § 1.1.0 Medium relevance — show source text

    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.

  • 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 § 10.5 Medium relevance — show source text

    10.5 and subsections_|||||||||||||||X|||||||||| |1.10.6 and subsections||||||||||||||||X||||||||| |1.11.0 through 1.11.11|||X|||||||||||||||||||||| |1.12.0|||||||||||||||||||||||X|| |1.13.0||||||||||||||||||||X||||| |1.14.0||||||||||||||||||||||||X| |Division II –
    Scope and Administration||||||||||||||||||||||||| |101.0 – 104.1||||||||||X|X|X|X|X|X|||||||||| |104.2 (Items 1 – 5)||||X|X|||||||||||||||||||| |104.3 – 107.0||||||||||X|X|X|X|X|X|||||||||| |104.4.3.1|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 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.

  • CMC § 1.8.2 Medium relevance — show source text

    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.

  • CMC § 1.11.0. Medium relevance — show source text
    Adopting Agency BSC BSC-
    CG
    SFM 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-
    CG
    SFM 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
    Adopt Entire Chapter as
    amended (amended sections
    listed below)
    Adopt only those sections
    that are listed below
    Chapter/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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    Part I – General.

    1701.0 General.

    1701.1 Applicability. Part I of this chapter shall apply to geothermal energy systems such as, but not limited to, building systems coupled with a ground-heat exchanger, submerged heat exchanger using water-based fluid as a heat transfer medium, or groundwater (well). The regulations of this chapter shall govern the construction, location and installation of geothermal energy systems.

    Part I through Part V of this chapter shall apply to geothermal energy systems and district ambient temperature loop systems that circulate ground-ambient-temperature water to be used in end-use buildings as a thermal source or sink via water source heat pump or reversing chiller. The systems shall operate to permit independent and bi-directional heating and cooling for comfort and water heating such as, but not limited to, building systems coupled with ground district ambient temperature loops, a ground-heat exchanger, submerged heat exchanger using water-based fluid as a heat transfer medium, or groundwater (well), or such local resources to the advantage of the district. Central district auxiliary components shall add or reject heat to benefit district ability to reduce both power consumption and demand combined with energy sharing. The regulations of this chapter shall govern the construction, location and installation of ground temperature thermal distribution districts from 100 percent geothermal energy system to multiple hybrid district systems.

  • CMC § 1-5 Medium relevance — show source text

    102 Construction Documents

    and Installation Verification . . . . . . . . . . . . . . . . . . . .1-5

    103 Building Standards Commission. . . . . . . . . . . . . . . . . . .1-5 104 Department of Housing and Community Development. . . . . . . . . . . . . . . . . .1-6 105 Division of the State Architect . . . . . . . . . . . . . . . . . . . . .1-6

    106 Office of Statewide Health Planning and Development . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-6

    CHAPTER 2 DEFINITIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3

    201 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-3

    202 Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-3

    CHAPTER 3 GREEN BUILDING . . . . . . . . . . . . . . . . . . . . . . . . 3-3

    301 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-3

    302 Mixed Occupancy Buildings . . . . . . . . . . . . . . . . . . . . . . .3-4 303 Phased Projects. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-4 304 Voluntary Tiers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-4 305 CALGreen Tier 1 and CALGreen Tier 2 . . . . . . . . . . . . . .3-4

    306 Voluntary Measures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-4

    CHAPTER 4 RESIDENTIAL MANDATORY MEASURES . . . . . . 4-3

    4.1 Planning and Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-3 4.2 Energy Efficiency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-7 4.3 Water Efficiency and Conservation . . . . . . . . . . . . . . . . .4-9 4.4 Material Conservation and Resource Efficiency . . . . 4-11 4.5 Environmental Quality . . . . . . . . . . . . . . . . . . . . . . . . . . 4-13

    CHAPTER 5 NONRESIDENTIAL MANDATORY MEASURES . . 5-3

  • CMC § 304.8 Medium relevance — show source text

    For SI units: 1 foot = 304.8 mm, 1 pound-force per square inch = 6.8947 kPa

    1112.12.5 Simultaneous Operation. When outlets of two or more relief devices or fusible plugs, which are

    TABLE 1112.12.4

    ATMOSPHERIC PRESSURE AT NOMINAL INSTALLATION ELEVATION ( Pa )

    [ASHRAE 15: TABLE 9-2]

    For SI units: 1 foot = 304.8 mm, 1 pound-force per square inch = 6.8947 kPa

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    REFRIGERATION

    1113.2 Type of Protection. Pressure vessels with an internal gross volume of 3 cubic feet (0.1 m [3] ) or less shall use one or more pressure relief devices or a fusible plug. Pressure vessels of more than 3 cubic feet (0.1 m [3] ) but less than 10 cubic feet (0.28 m [3] ) internal gross volume shall use one or more pressure relief devices. Fusible plugs shall not be used.

    [ASHRAE 15:9.7.2.1, 9.7.2.2]

    1113.3 Discharging into Lowside of System. For pressure-relief valves discharging into the lowside of the system, a single relief valve (not rupture member) of the required relieving capacity shall not be used on vessels of 10 cubic feet (0.28 m [3] ) or more internal gross volume except under the conditions permitted in Section 1112.11.3. [ASHRAE 15:9.7.3]

    1113.4 Parallel Pressure-Relief Devices. Two or more

    pressure-relief devices in parallel to obtain the required capacity shall be considered as one pressure-relief device. The discharge capacity shall be the sum of the capacities required for each pressure vessel being protected.

    1113.5 Discharge Capacity. The minimum required discharge capacity of the pressure-relief device or fusible plug for a pressure vessel shall be determined in accordance with ASHRAE 15.

    1113.6 Three-Way Valve. Pressure vessels of 10 cubic feet (0.28 m [3] ) or more internal gross volume shall use one or more rupture member(s) or dual pressure-relief valves where discharging to the atmosphere. Dual pressure-relief valves shall be installed with a three-way valve to allow testing or repair. Where dual relief valves are used, the valve shall comply with Section 1113.5.

    Exception: A single relief valve shall be permitted on pressure vessels of 10 cubic feet (0.28 m [3] ) or more internal gross volume where in accordance with the following conditions:

    (1) The relief valves are located on the lowside of the sys tem.

    (2) The vessel is provided with shutoff valves designed to allow pumpdown of the refrigerant charge of the pressure vessel.

    (3) Other pressure vessels in the system are separately protected in accordance with Section 1113.1. [ASHRAE 15:9.7.2.3]

    1114.0 Special Discharge Requirements.

  • CMC § 3.3.101 Medium relevance — show source text

    [NFPA 54:3.3.101]

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    DEFINITIONS

    Water Well. An excavation that is drilled, cored, bored, washed, driven, dug, jetted, or otherwise constructed for the purposes of extracting groundwater, using the geothermal properties of the earth or injecting water into an aquifer or subsurface reservoir.

    226.0 – X –

    No definitions.

    227.0 – Y –

    No definitions.

    228.0 – Z –

    Zeotropic. Blends comprising multiple components of different volatilities that, when used in refrigeration cycles, change volumetric composition and saturation temperatures as they evaporate (boil) or condense at constant pressure.

    [ASHRAE 34:3]

    Zone. [OSHPD 1, 2, 3, 4 & 5] A space or group of spaces within a building for which the heating, or cooling require- ments are sufficiently similar that desired conditions can be maintained throughout by a single controlling device.

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    CALIFORNIA MECHANICAL CODE – MATRIX ADOPTION TABLE

    CHAPTER 3 – GENERAL REGULATIONS

    (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-
    CG
    SFM 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-
    CG
    SFM 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
    Adopt Entire Chapter as
    amended (amended sections
    listed below)
    X X X X X X X X X
    Adopt only those sections
    that are listed below
    X
    Chapter/Section
    301.7 X
    303.
  • CMC § 1.12.0 Medium relevance — show source text

    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.

    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.

Frequently asked questions

What does §301.1 (Applicability) require?

Section §301.1 explains that Chapter 3 applies to general requirements for heating, ventilating, air‑conditioning, refrigeration and other energy‑utilizing equipment and appliances — in short, it sets the scope for these cross‑cutting rules.

Where are approval and electrical requirements stated?

Equipment approval and listing requirements are in §301.2 (approval/listing by an authority having jurisdiction or nationally recognized standards), and electrical connection/disconnect and receptacle requirements are in §301.4.

How does Chapter 3 relate to other CMC chapters and referenced standards?

Chapter 3 provides foundational rules used throughout the CMC and directs users to referenced standards collected in Chapter 18; specific appliance or system chapters then add technical requirements on top of Chapter 3’s general provisions.

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