CMC · California Mechanical Code
Installation of Specific Appliances
Chapter 9 of the California Mechanical Code governs minimum installation requirements for specific (mostly nonindustrial) appliances and points to related provisions for combustion air, venting, clearances, and manufacturer instructions.
Last reviewed: July 6, 2026
Overview
Chapter 9 of the California Mechanical Code (CMC) sets minimum design, construction, and installation requirements for a wide range of appliances (nonindustrial and listed equipment), and directs users to the general appliance provisions in Chapter 3; see §901.1 and §902.1 for applicability and scope.
This area of the code matters because it ties appliance safety to combustion air, venting, clearances, structural support, and listing/manufacturer instructions. Key cross‑references include combustion‑air requirements in Chapter 7 (see Section 701.4 and related discussion), venting system rules in Chapter 8/§802.0, and clearance/protection provisions such as §303.10 — all of which work together to prevent hazards like backdrafting, carbon monoxide, fire, and mechanical failure.
Chapter 9 contains many appliance‑specific sections (examples: clothes dryers at §908.0, unit and food‑service appliances in the 910–918 range, ductless mini‑split installation at §934.0) and points users to manufacturer instructions and listings as the primary installation authority for listed appliances. Consult these individual sections for particular appliances and the related exhaust/makeup‑air requirements found elsewhere in the code (for example, clothes‑dryer exhaust rules in Chapter 5).
In this section
Code references
Grounded in the retrieved California Mechanical Code — click a citation to read the verbatim passage:
CMC § 25.4 High relevance — show source text
(1) Unit heaters shall be installed with clearances from combustible material of not less than 18 inches (457 mm) at the sides, 12 inches (305 mm) at the bottom, and 6 inches (152 mm) above the top where the unit heater has an internal draft hood, or 1 inch (25.4 mm) above the top of the sloping side of a vertical draft hood. A unit heater listed for reduced clearances shall be installed in accordance with its listing and the manufacturer’s installation instructions.
(2) Clearances for servicing shall be in accordance with the manufacturer’s installation instructions. {NFPA 54:10.24.3}
916.3.1 Floor-Mounted-Type Unit Heaters. Floormounted-type unit heaters shall comply with the following requirements:
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INSTALLATION OF SPECIFIC APPLIANCES
permitted where protected in accordance with Table 303.10.1.
[NFPA 54:10.11.5] 917.6 Use with Casters. Floor-mounted appliances with casters shall be listed for such construction and shall be
installed in accordance with the manufacturer’s installation instructions for limiting the movement of the appliance to prevent strain on the connection. [NFPA 54:10.11.6]
917.7 Level Installation. Floor-mounted food service appliances shall be installed level on a firm foundation.
[NFPA 54:10.11.7]
917.8 Ventilation. Means shall be provided to properly ventilate the space in which a food service appliance is installed to permit proper combustion of the gas. [NFPA 54:10.11.8]
918.0 Food Service Appliances, Counter Appliances.
918.1 Application. Food service counter appliances shall be listed in accordance with ANSI Z83.11/CSA 1.8. [NFPA 54:10.12.1]
918.2 Vertical Clearance. A vertical distance of not less than 48 inches (1219 mm) shall be provided between the top of all food service hot plates and griddles and combustible material. [NFPA 54:10.12.2]
918.3 Clearance for Listed Appliances. Listed food service counter appliances such as hot plates and griddles, food and dish warmers, and coffee brewers and urns, where installed on combustible surfaces, shall be set on their own bases or legs and shall be installed with a horizontal clearance of not less than 6 inches (152 mm) from combustible material, except that not less than a 2 inches (51 mm) clearance shall be maintained between a draft hood and combustible material. Food service counter appliances listed for installation at lesser clearances shall be installed in accordance with their listing and the manufacturer’s installation instructions.
918.4 Clearance for Unlisted Appliances. Food service counter appliances, where installed on combustible surfaces, shall be installed with a minimum horizontal clearance of 6 inches (152 mm) from combustible material, except that at least a 2 inch (51 mm) clearance shall be maintained between a draft hood and combustible material. Food service counter appliances listed for installation at lesser clearances shall be installed in accordance with the manufacturer’s installation instructions. [NFPA 54:10.12.3]
CMC § 911.0 High relevance — show source text
2||||||||||X|X|X||X|X|||||||||| |911.0||||||||||||||||||X||||||| |911.2||||||||||X|X|X||X|X|||||||||| |912.3(1)||||X|X|||||||||||||||||||| |915.3.1||||X|X|||||||||||||||||||| |915.3.1.1||||X|X|||||||||||||||||||| |929.0||||†|†|||||||||||||||||||| |929.1||||†|†||||||||||||||||||||
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 9
INSTALLATION OF SPECIFIC APPLIANCES
901.0 General.
901.1 Applicability. This chapter addresses requirements for the design, construction, and installation of specific appliances. In addition to the requirements of this chapter, appliances shall comply with the general requirements of Chapter 3.
902.0 General.
902.1 Nonindustrial Appliances. This chapter is applicable primarily to nonindustrial-type appliances and installations and, unless specifically indicated, does not apply to industrial-type appliances and installations. Listed appliances shall be installed in accordance with their listing and the manufacturer’s installation instructions or, as elsewhere specified in this chapter, as applicable to the appliance. Unlisted appliances shall be installed as specified in this part as applicable to the appliances.
902.2 Combustion Air from Bedroom or Bathroom. Appliances shall not be installed so their combustion, ventilation, and dilution air are obtained only from a bedroom or bathroom unless the bedroom or bathroom has the required volume in accordance with Section 701.4. [NFPA 54:10.1.2]
[OSHPD 1, 1R, 2, 4 & 5] Warm air furnaces shall not be installed under openable windows on exterior walls. 902.3 Added or Converted Appliances. When additional or replacement appliances or equipment is installed or an appliance is converted to gas from another fuel, the location in which the appliances or equipment is to be operated shall be checked to verify the following:
(1) Air for combustion and ventilation is provided where required, in accordance with the provisions of Section 701.0. Where existing facilities are not adequate, they shall be upgraded to meet Section 701.0 specifications.
(2) The installation components and appliances meet the clearances to combustible material provisions of Section 303.10. It shall be determined that the installation and operation of the additional or replacement appliances do not render the remaining appliances unsafe for continued operation.
(3) The venting system is constructed and sized in accordance with the provisions of Section 802.0.
CMC § 9.1.6.2 High relevance — show source text
** Nondirect-vent appliances installed in beauty shops, barber shops, or other facilities where chemicals that generate corrosive or flammable products such as aerosol sprays are routinely used shall be located in a mechanical room separate or partitioned off from other areas with provisions for combustion and dilution air from outdoors. Direct vent appliances in such facilities shall be in accordance with the appliance manufacturer’s installation instructions. [NFPA 54:9.1.6.2]
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INSTALLATION OF SPECIFIC APPLIANCES
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903.2.3 Connection of Gas Engine-Powered Air Conditioners. Gas engines shall not be rigidly connected to the gas supply piping. [NFPA 54:10.2.3]
903.2.4 Clearances for Indoor Installation. The installation of air-conditioning appliances shall comply with the following requirements:
(1) Air-conditioning appliances shall be installed with clearances in accordance with the terms of their listing and the manufacturer’s instructions. {NFPA 54:10.2.4(1)}
(2) Air-conditioning appliances shall be permitted to be installed with reduced clearances to combustible material, provided that the combustible material or appliance is protected as described in Table 303.10.1 and such reduction is allowed by the manufacturer’s installation instructions. [NFPA 54:10.2.4(2)]
(3) Where the furnace plenum is adjacent to plaster on metal lath or noncombustible material attached to
combustible material, the clearance shall be measured to the surface of the plaster or other noncombustible finish where the clearance specified is 2 inches (51 mm) or less. [NFPA 54:10.2.4(3)]
(4) Air-conditioning appliances shall have the clearance from supply ducts within 3 feet (914 mm) of the furnace plenum be not less than that specified from the furnace plenum. No clearance is necessary beyond this distance. [NFPA 54:10.2.4(4)]
903.2.5 Assembly and Installation. Unless the airconditioning appliance is listed for installation on a combustible surface, or unless the surface is protected in an approved manner, it shall be installed on a surface of noncombustible construction with noncombustible mate rial and surface finish and with no combustible material against the underside thereof. [NFPA 54:10.2.5]
903.2.6 Refrigeration Coils. The installation of refrigeration coils shall be in accordance with Section 904.8 and Section 904.9. [NFPA 54:10.2.7]
903.2.7 Switches in Electrical Supply Line. Means for interrupting the electrical supply to the air-conditioning appliance and to its associated cooling tower shall be in accordance with NFPA 70. [NFPA 54:10.2.8]
903.3 Packaged Terminal Air Conditioners. Packaged terminal air conditioners and heat pumps shall comply with UL 484 or UL 60335-2-40, and shall be installed in accordance with the manufacturer’s installation instructions.
904.0 Central Heating Boilers and Furnaces.
904.1 Application. Central heating furnaces and boilers shall be listed in accordance with the following:
CMC § 933.2 High relevance — show source text
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INSTALLATION OF SPECIFIC APPLIANCES
933.2 Unit Coolers. Factory-built unit coolers for use in refrigerators, freezers, refrigerated warehouses, and walk-in coolers shall comply with UL 412 or UL 60335-2-89 and shall be installed in accordance with the manufacturer’s
installation instructions.
933.3 Self-Contained Mechanical Refrigeration Sys- tems. Self-contained mechanical refrigeration systems for use in walk-in coolers shall comply with UL 427 or UL 60335-2-89 and shall be installed in accordance with the man ufacturer’s installation instructions.
934.0 Ductless Mini-Split Systems Installation.
934.1 General. A ductless mini-split system installation shall be installed in accordance with the manufacturer’s
installation instructions and Section 310.2 for condensate
control.
935.0 Air Filter Appliances.
935.1 Electrostatic Air Cleaners. Electrostatic air cleaners shall comply with UL 867 and installed in accordance with the manufacturer’s installation instructions.
935.2 High-Efficiency Particulate Air Filter Units. High-efficiency particulate air filter units for use in industrial and laboratory exhaust and ventilation systems shall be installed in accordance with the manufacturer’s installation
instructions.
936.0 Gaseous Hydrogen Systems.
936.1 General. Gaseous hydrogen systems shall be installed in accordance with NFPA 2.
937.0 Compressed Natural Gas (CNG) Vehicular Fuel Systems.
937.1 General. The installation of compressed natural gas (CNG) fueling (dispensing) systems shall be in accordance with NFPA 52. Residential CNG fueling appliances shall be listed in accordance with ANSI/CSA NGV 5.1 and installed in accordance to the appliance manufacturer’s installation instructions. Non-residential CNG fueling appliances shall be listed in accordance with ANSI/CSA NGV 5.2 and installed in accordance with the appliance manufacturer’s installation instructions. [NFPA 54:10.27]
938.0 Dehumidifiers.
938.1 General. Dehumidifiers shall comply with UL 603352-40, and be installed in accordance with the manufacturer’s installation instructions.
939.0 Sauna Heaters.
939.1 Electric Sauna Heaters. Sauna heaters shall comply with UL 875 and shall be installed in accordance with the manufacturer’s installation instructions.
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CALIFORNIA MECHANICAL CODE – MATRIX ADOPTION TABLE
CHAPTER 10 – BOILERS AND PRESSURE VESSELS
(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.)
CMC § 2025 High 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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FORMAT OF THE UNIFORM MECHANICAL CODE
CMC § 9.1.8.1 High relevance — show source text
** Appliances and equipment shall be furnished either with load-distributing bases or with a sufficient number of supports to prevent damage to either the building structure or the appliance and the equipment.
[NFPA 54:9.1.8.1] 902.8.1 Structural Capacity. At the locations selected for installation of appliances and equipment, the dynamic and static load-carrying capacities of the building structure shall be checked to determine whether they are adequate to carry the additional loads. The appliances and equipment shall be supported and shall be connected to the piping so as not to exert undue stress on the connections. [NFPA 54:9.1.8.2] 902.9 Flammable Vapors. Appliances shall not be installed in areas where the open use, handling, or dispensing of flammable liquids occurs, unless the design, operation, or installation reduces the potential of ignition of the flammable vapors. Appliances installed in compliance with Section 305.1 through Section 305.1.2, Section 303.11, or Section 303.12 shall be considered to comply with the intent of this provision. [NFPA 54:9.1.9] 902.10 Solid-Fuel-Burning Appliances. Unless otherwise specified, solid-fuel-burning appliances shall be installed in accordance with NFPA 211 and the manufacturer’s instal lation instructions.
902.11 Combination of Appliances and Equipment. Any combination of appliances, equipment, attachments, or devices used together in any manner shall comply with the standards that apply to the individual appliance and equipment. [NFPA 54:9.1.19] 902.12 Protection of Gas Appliances from Fumes or Gases Other than Products of Combustion. Nondirect-vent appliances installed in beauty shops, barber shops, or other facilities where chemicals that generate corrosive or flammable products such as aerosol sprays are routinely used shall be located in a mechanical room separate or partitioned off from other areas with provisions for combustion and dilution air from outdoors. Direct vent appliances in such facilities shall be in accordance with the appliance manufacturer’s installation instructions. [NFPA 54:9.1.6.2]
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INSTALLATION OF SPECIFIC APPLIANCES
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903.2.3 Connection of Gas Engine-Powered Air Conditioners. Gas engines shall not be rigidly connected to the gas supply piping. [NFPA 54:10.2.3]
903.2.4 Clearances for Indoor Installation. The installation of air-conditioning appliances shall comply with the following requirements:
(1) Air-conditioning appliances shall be installed with clearances in accordance with the terms of their listing and the manufacturer’s instructions. {NFPA 54:10.2.4(1)}
(2) Air-conditioning appliances shall be permitted to be installed with reduced clearances to combustible material, provided that the combustible material or appliance is protected as described in Table 303.10.1 and such reduction is allowed by the manufacturer’s installation instructions. [NFPA 54:10.2.4(2)]
(3) Where the furnace plenum is adjacent to plaster on metal lath or noncombustible material attached to
CMC § 920.3 High relevance — show source text
920.3 Oil-Burning Ranges. Oil-burning ranges shall comply with UL 896 and installed in accordance with the manufacturer’s installation instructions.
921.0 Open-Top Broiler Units.
921.1 Application. Open-top broiler units shall be listed in accordance with ANSI Z83.11/CSA 1.8 or ANSI/CSA
Z21.1/CSA 1.1 and installed in accordance with the manu facturer’s installation instructions. [NFPA 54:10.17.1]
921.2 Protection Above Domestic Units. Domestic opentop broiler units shall be provided with a metal ventilating hood not less than 0.0122 of an inch (0.3099 mm) thick with a clearance of not less than [1] ⁄ 4 of an inch (6.4 mm) between the hood and the underside of combustible material or metal cabinets. A
clearance of at least 24 inches (610 mm) shall be maintained between the cooking top and the combustible material or metal cabinet, and the hood shall be at least as wide as the open-top broiler unit and centered over the unit. Domestic open-top broiler units incorporating an integral exhaust system and listed for use without a ventilating hood shall not be required to be provided with a ventilating hood if installed in accordance with Section 919.4.2(1). [NFPA 54:10.17.2]
921.3 Commercial Units. Commercial open-top broiler units shall be provided with ventilation in accordance with Chapter 5, Part II. {NFPA 54:10.17.3}
922.0 Outdoor Cooking Appliances.
922.1 Application. Outdoor cooking appliances shall be listed in accordance with ANSI Z83.11/CSA 1.8, ANSI Z21.58/CSA 1.6, or ANSI Z21.89/CSA 1.18, and installed in accordance with the manufacturer’s installation instructions.
[NFPA 54:10.18]
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INSTALLATION OF SPECIFIC APPLIANCES
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923.0 Illuminating Appliances.
923.1 Clearances for Listed Appliances. Listed illuminating appliances shall be installed in accordance with their listing and the manufacturer’s installation instructions. {NFPA 54:10.14.1}
923.2 Clearances for Unlisted Appliances. Clearances for unlisted illuminating appliances shall comply with the following:
(1) Unlisted enclosed illuminating appliances installed outdoors shall be installed with clearances in any direction from combustible material of not less than 12 inches (305 mm). [NFPA 54:10.14.2.1(1)]
(2) Unlisted enclosed illuminating appliances installed indoors shall be installed with clearances in any direction from combustible material of not less than 18 inches
(457 mm). [NFPA 54:10.14.2.1(2)]
923.2.1 Open-Flame Type. Clearance shall comply with the following:
CMC § 922.0 High relevance — show source text
922.0 Outdoor Cooking Appliances.
922.1 Application. Outdoor cooking appliances shall be listed in accordance with ANSI Z83.11/CSA 1.8, ANSI Z21.58/CSA 1.6, or ANSI Z21.89/CSA 1.18, and installed in accordance with the manufacturer’s installation instructions.
[NFPA 54:10.18]
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INSTALLATION OF SPECIFIC APPLIANCES
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923.0 Illuminating Appliances.
923.1 Clearances for Listed Appliances. Listed illuminating appliances shall be installed in accordance with their listing and the manufacturer’s installation instructions. {NFPA 54:10.14.1}
923.2 Clearances for Unlisted Appliances. Clearances for unlisted illuminating appliances shall comply with the following:
(1) Unlisted enclosed illuminating appliances installed outdoors shall be installed with clearances in any direction from combustible material of not less than 12 inches (305 mm). [NFPA 54:10.14.2.1(1)]
(2) Unlisted enclosed illuminating appliances installed indoors shall be installed with clearances in any direction from combustible material of not less than 18 inches
(457 mm). [NFPA 54:10.14.2.1(2)]
923.2.1 Open-Flame Type. Clearance shall comply with the following:
(1) Unlisted open-flame illuminating appliances installed outdoors shall have clearances from com bustible material not less than that specified in Table 923.2.1. The distance from ground level to the base of the burner shall be a minimum of 7 feet (2134 mm) where installed within 2 feet (610 mm) of walkways. Lesser clearances shall be permitted to be used where acceptable to the Authority Having Jurisdiction.
(2) Unlisted open-flame illuminating appliances installed outdoors shall be equipped with a limiting orifice or other limiting devices that maintain a flame height consistent with the clearance from combustible material, as given in Table 923.2.1.
(3) Appliances designed for flame heights in excess of 30 inches (762 mm) shall be approved. Such appliances shall be equipped with a safety shutoff device or automatic ignition.
(4) Clearances to combustible material from unlisted open-flame illuminating appliances shall be approved. [NFPA 54:10.14.2.2]
TABLE 923.2.1
CLEARANCES FOR UNLISTED OUTDOOR
OPEN-FLAME ILLUMINATING APPLIANCES
[NFPA 54:TABLE 10.14.2.2]
923.3 Mounting on Buildings. Illuminating appliances designed for installation on a wall or ceiling shall be securely attached to substantial structures in such a manner that they are not dependent on the gas piping for support. [NFPA 54:10.14.3]
CMC § 902.2 High relevance — show source text
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 Adopt Entire Chapter as
amended (amended sections
listed below)X X X X X X X Adopt only those sections
that are listed belowX Chapter/Section 902.2 X X X X X 911.0 X 911.2 X X X X X 912.3(1) X X 915.3.1 X X 915.3.1.1 X X 929.0 † † 929.1 † † 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 9
INSTALLATION OF SPECIFIC APPLIANCES
901.0 General.
901.1 Applicability. This chapter addresses requirements for the design, construction, and installation of specific appliances. In addition to the requirements of this chapter, appliances shall comply with the general requirements of Chapter 3.
902.0 General.
CMC § 902.10 Medium relevance — show source text
Burning appliances . . . . . . . . . . . . . . . . . . . . . . . 902.10 Chimney, combination
gas- and solid-fuel. . . . . . . . . . . . . . . . . . . . 802.5.8.2 Cooking operations . . . . . . . . . . . . . . . . . . . . . . . . 517.0
Furnace . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 904.11
Room heaters . . . . . . . . . . . . . . . . . . . . . . . . . . . . 915.4
Venting. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 801.3
SPARK ARRESTERS
Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 221.0
Solid-fuel cooking operations . . . . . . . . . . . . . . . 517.1.6
SPECIFIC APPLIANCES,
INSTALLATION OF . . . . . . . . . . . . . . . . . . . . . . Chapter 9
STANDARDS
Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 221.0
General . . . . . . . . . . . . . . . . . . . . . . . . . . 301.2, 302.1.2
Fire-extinguishing systems. . . . . . . . . . . . . . . . . 513.2.2
Fuel gas piping. . . . . . . . . . . . . . . . . . . . . . . . . . D 115.1
Hydronics . . . . . . . . . . . . . 1203.2, 1207.3, Table 1210.1
Oil-or liquid-fuel
burning equipment. . . . . . . . . . . . . . . . . . . . . C 103.0 Referenced. . . . . . . . . . . . . . . . . . . . . . . . . . Chapter 18
Steam and hot water boilers . . . . . . . . . . . . . . . . 1002.0
STATIONARY
Engine generators. . . . . . . . . . . . . . . . . . . . . . . . 1602.0
Fuel Cell Power Plant . . . . . . . . . . . . . . . . 221.0, 1601.0
Gas Engines . . . . . . . . . . . . . . . . . . . . . . . . . . . .1602.0
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INDEX
STEAM AND HOT-WATER SYSTEMS (Hospitals) . . . .319.0
CMC § 420.6.2 Medium relevance — show source text
Exception: Spaces having a direct exit to a public way.
420.6.2 Refuge area. Refuge areas shall be provided within each smoke compartment. The size of the refuge area shall accommodate the occupants and care recipients from the adjoining smoke compartment. Where a smoke compartment is adjoined by two or more smoke compartments, the minimum area of the refuge area shall accommodate the largest occupant load of the adjoining compartments. The size of the refuge area shall provide the following:
- Not less than 15 net square feet (1.4 m [2] ) for each care recipient.
- Not less than 6 net square feet (0.56 m [2] ) for other occupants.
Areas or spaces permitted to be included in the calculation of the refuge area are corridors, lounge or dining areas and other low-hazard areas.
420.7 Reserved.
420.8 Reserved.
420.9 Domestic cooking appliances. In Group R-2.1 occupancies, installation of cooking appliance used in domestic cooking facilities shall comply with all of the following:
- The types of cooking appliances permitted shall be limited to ovens, cooktops, ranges, warmers and microwaves.
- Domestic cooking hoods installed and constructed in accordance with the California Mechanical Code shall be provided over cooktops or ranges.
- Cooktops and ranges shall be protected in accordance with Section 904.15.
- A shutoff for the fuel and electrical supply to the cooking equipment shall be provided in a location to which only staff has
access.
A timer shall be provided that automatically deactivates the cooking appliances within a period of not more than 120 minutes.
A portable fire extinguisher shall be provided. Installation shall be in accordance with Section 906 and the extinguisher shall be located within a 30-foot (9144 mm) distance of travel from each domestic cooking appliance.
Exceptions:
- Cooking facilities provided within care recipients’ individual dwelling units are not required to comply with this section.
- Cooktops and ranges used for care-recipient training or nutritional counseling are not required to comply with Item 3 of this section.
420.10 Group R cooking facilities. In Group R occupancies, cooking appliances used for domestic cooking operations shall be in accordance with the California Mechanical Code .
420.11 Group R-2 dormitory cooking facilities. Domestic cooking appliances for use by residents of Group R-2 college dormitories shall be in accordance with Sections 420.11.1 and 420.11.2.
420.11.1 Cooking appliances. Where located in Group R-2 college dormitories, domestic cooking appliances for use by residents shall be in compliance with all of the following:
The types of domestic cooking appliances shall be limited to ovens, cooktops, ranges, warmers, coffee makers and microwaves.
Domestic cooking appliances shall be limited to approved locations.
Cooktops and ranges shall be protected in accordance with Section 904.15.
Cooktops and ranges shall be provided with a domestic cooking hood installed and constructed in accordance with the California Mechanical Code . Kitchen range hoods shall also be rated for sound and meet field verification requirements in the California Energy Code for low-rise and high-rise residential buildings.
420.11.2 Cooking appliances in sleeping rooms. Cooktops, ranges and ovens shall not be installed or used in sleeping rooms.
CMC § 101.5 Medium relevance — show source text
101.5 Referenced codes and standards. The codes and standards referenced elsewhere in this code shall be considered part of the requirements of this code to the prescribed extent of each such reference.
101.5.1 Building. The provisions of the California Building Code, California Residential Code and California Existing Building Code, as applicable, shall apply to the construction, alteration, movement, enlargement, replacement, repair, use and occupancy, location, maintenance, removal and demolition of every structure or any appurtenances connected or attached to such buildings or structures.
101.5.2 Electrical. The provisions of the California Electrical Code shall apply to the installation of electrical systems, including but not limited to, alterations, repair, replacement, equipment, appliances, fixtures, fittings and appurtenances thereto.
2025 CALIFORNIA GREEN BUILDING STANDARDS CODE 1-3
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
ADMINISTRATION
101.5.3 Mechanical. The provisions of the California Mechanical Code shall apply to the installation, alterations, repair and replacement of mechanical systems, including equipment, appliances, fixtures, fittings and/or appurtenances, including ventilating, heating, cooling, air-conditioning and refrigeration systems, incinerators and other energy-related systems.
101.5.4 Plumbing. The provisions of the California Plumbing Code shall apply to the installation, alteration, repair and replacement of plumbing systems, including equipment, appliances, fixtures, fittings and appurtenances where connected to a water or sewage system.
101.5.5 Fire prevention. The provisions of CCR, Title 19, Division 1 and CCR, Title 24, Part 2 and Part 9 relating to fire and panic safety as adopted by the Office of the State Fire Marshal shall apply to all structures, processes and premises for protection from the hazard of fire, panic and explosion.
101.5.6 Energy. The provisions of the California Energy Code shall apply to the minimum design and construction of buildings for energy efficiency.
101.6 Order of precedence and use.
101.6.1 Differences. In the event of any differences between these building standards and the standard reference documents, the text of these building standards shall govern. In the event a local amendment to this code results in differences between these building standards and the amendment, the text of the amendment shall govern.
101.6.2 Specific provision. Where a specific provision varies from a general provision, the specific provision shall apply.
101.6.3 Conflicts. When the requirements of this code conflict with the requirements of any other part of the California Building Standards Code, Title 24, the most restrictive requirement shall prevail.
101.6.4 Explanatory notes. Explanatory material, such as references to websites or other sources where additional information may be found, is included in this code in the form of notes. Notes are informational only and are not enforceable requirements of this code.
101.7 City, county, or city and county amendments, additions or deletions. This code is intended to set mandatory minimum Green Building Standards and includes optional tiers that may, at the discretion of any city, county, or city and county, be applied.
Frequently asked questions
Which CMC sections set the basic applicability and installation authority for specific appliances?
Chapter 9 establishes applicability and general installation rules — see §901.1 and §902.1 — and states that listed appliances must be installed per their listing and the manufacturer’s instructions.
What rules govern combustion air and venting for appliances?
Combustion air requirements are handled in Chapter 7 (see Section 701.4 and related provisions) and venting system design and sizing are in Chapter 8 (including §802.0); Chapter 9 directs installers to those chapters when appliance safety depends on combustion air or venting.
Where are clothes‑dryer exhaust and makeup‑air requirements found?
Dryer exhaust construction, termination, makeup‑air, and length limits are addressed in the exhaust chapter (Chapter 5, e.g., §504.4 and related provisions) and must terminate outdoors with specified materials, backdraft protection, and makeup‑air where required.
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