Key 'A' definitions: Accessible, Approved, Appliance, Listed/Labeled

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

• CMC § 3.3.53 High relevance — show source text

  Valves, Companion or Block. Pairs of mating stop valves valving off sections of refrigeration systems and arranged so that these sections may be joined before opening these valves or separated after closing them.

  Vent. A pipe or other conduit composed of factory-made components, containing a passageway for conveying combustion products and air to the atmosphere, listed and labeled for use with a specific type or class of appliance. Vent, Type B Gas. A factory-made gas vent listed by a nationally recognized testing agency for venting listed or approved appliances equipped to burn only gas. Vent, Type B-W Gas. A factory-made gas vent listed by a nationally recognized testing agency for venting listed or approved gas-fired vented wall furnaces. Vent, Type L Gas. A venting system consisting of listed vent piping and fittings for use with oil-burning appliances listed for use with Type L or with listed gas appliances. Vent, Gas. A passageway composed of listed factory-built components assembled in accordance with the manufacturer’s installation instructions for conveying vent gases from appliances or their vent connectors to the outdoors. [NFPA 54:3.3.53] Vent Connector, Gas. That portion of a gas-venting system that connects a listed gas appliance beginning at the draft hood or flue collar to a gas vent and is installed entirely within the space or area in which the appliance is located. Vent Offset. An arrangement of two or more fittings and pipe installed for the purpose of locating a vertical section of vent pipe in a different but parallel plane with respect to an adjacent section of vertical vent pipe. [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.)

• CMC § 1312.1 Medium relevance — show source text

  Materials addressed in Section 1312.1(2), Section 1312.1(3), Section 1312.1(4), Section 1312.1(5), and Section 1312.1(6) shall not be installed through an opening in an appliance housing, cabinet, or casing, unless the tubing or connector is protected against damage.

  [NFPA 54:9.6.1.2]

  1312.1.2 Food Service Appliance Connectors. Connectors used with food service appliances that are moved for cleaning and sanitation purposes shall be installed in accordance with the connector manufacturer’s installation

  instructions. Such connectors shall be listed in accordance

  with ANSI Z21.69/CSA 6.16. [NFPA 54:9.6.1.3]

  1312.1.3 Restraining Device. Movement of appliances with casters shall be limited by a restraining device installed in accordance with the connector and appliance manufacturer’s installation instructions. [NFPA 54:9.6.1.4]

  1312.2 Suspended Low-Intensity Infrared Tube Heaters. Suspended low-intensity infrared tube heaters shall be connected to the building piping system with a connector listed for the application in accordance with ANSI Z21.24/CSA 6.10 as follows:

  (1) The connector shall be installed in accordance with the tube heater installation instructions, and shall be in the same room as the appliance.

  (2) Only one connector shall be used per appliance. [NFPA 54:9.6.1.5]

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  FUEL GAS PIPING

  length and shall not extend from one room to another or pass through any walls, partitions, ceilings, or floors. Flexible connections shall not be used in any concealed location. They shall be protected against physical or thermal damage and shall be provided with gas shutoff valves in readily accessible locations in rigid piping upstream from the flexible connections. [NFPA 54:9.6.4.4]

  1312.6 Appliance Shutoff Valves and Connections. Each appliance connected to a piping system shall have an accessible, approved manual shutoff valve with a nondisplaceable valve member, or a listed gas convenience outlet. Appliance shutoff valves and convenience outlets shall serve a single appliance only. [NFPA 54:9.6.5] The shutoff valve shall be located within 6 feet (1829 mm) of the appliance it serves. [NFPA 54:9.6.5.1] Where a connector is used, the valve shall be installed upstream of the connector. A union or flanged connection shall be provided downstream from the valve to permit removal of appliance controls. [NFPA 54:9.6.5.1(A)]

  Exceptions:

  (1) Shutoff valves serving decorative appliances in a fireplace shall not be located within the fireplace firebox except where the valve is listed for such use. [NFPA 54: 9.6.5.1(B)]

  (2) Shutoff valves shall be permitted to be accessibly located inside wall heaters and wall furnaces listed for recessed

  installation where necessary maintenance is performed without removal of the shutoff valve.

• CMC § 3.3.5 Medium relevance — show source text

  Air Dispersion Systems. Materials intended for use in air handling systems in exposed locations operating under positive pressure.

  Air Exfiltration. Leakage of air from a conditioned space(s) to an unconditioned space(s) or to the outdoors through openings in the building envelope, often attributable to wind pressure, stack pressure, or positive pressurization of the building. Also known as air leakage.

  Air-Handling Unit. A blower or fan used for the purpose of distributing supply air to a room, space, zone, or area.

  Air Infiltration. Leakage of outdoor air or air from an unconditioned space(s) into a conditioned space(s) through openings in the building envelope, often attributable to wind pressure, stack pressure, or negative pressurization of the building. Also known as air leakage.

  Air Intakes. An opening in a building’s envelope whose purpose is to allow outside air to be drawn into the structure to

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  DEFINITIONS

  contained fuel supply and is not secured or attached to a building by any means other than by a factory-installed power supply cord.

  Appliance, Vented. An appliance designed and installed in such a manner that all products of combustion are conveyed directly from the appliance to the outdoor atmosphere through an approved chimney or vent system. Appliance Categorized Vent Diameter/Area. The minimum vent diameter/area permissible for Category I appliances to maintain a nonpositive vent static pressure when tested in accordance with nationally recognized standards.

  [NFPA 54:3.3.5]

  Appliance Flue Outlet. The opening or openings in a cooking device where vapors, combustion gases, or both leave the cooking device. [NFPA 96:3.3.4] There might or might not be ductwork attached to this opening. Appliance Fuel Connector. An assembly of listed semirigid or flexible tubing and fittings to carry fuel between a fuel-piping outlet and a fuel-burning appliance.

  Approved. Acceptable to the Authority Having Jurisdiction.

  Exception: [HCD 1 & HCD 2] “Approved” means meeting the approval of the Enforcing Agency, except as otherwise provided by law, when used in connection with any system, material, type of construction, fixture or appliance as the result of investigations and tests conducted by the agency, or by reason of accepted principles or tests by national author- ities, or technical, health, or scientific organizations or agen- cies.

  Notes :

  (1) See Health and Safety Code Section 17920 for “Approved” as applied to residential construction and buildings or structures accessory thereto, as referenced in Sections 1.8.2.1.1 and 1.8.2.1.2.

  (2) See Health and Safety Code Section 17921.1 for “A pproved” as applied to the use of hotplates in resi- dential construction referenced in Sections 1.8.2.1.1 and 1.8.2.1.2.

  (3) See Health and Safety Code Section 19966 for “Approved” as applied to Factory-Built Housing as ref- erenced in Sections 1.8.2.1.1 and 1.8.2.1.2.

• CMC § 2308.2 Medium relevance — show source text

  2308.2 Approvals. Storage vessels and equipment used for the storage, compression or dispensing of CNG shall be approved or listed in accordance with Sections 2308.2.1 through 2308.2.4.

  2308.2.1 Approved equipment. Containers, compressors, pressure relief devices (including pressure relief valves), and pressure regulators and piping used for CNG shall be approved.

  2308.2.2 Listed equipment. Hoses, hose connections, dispensers and electrical equipment used for CNG shall be listed. Vehiclefueling connections shall be listed and labeled.

  2308.2.3 Residential fueling appliance (RFA). Residential fueling appliances shall be listed and installed in accordance with the installation requirements of CSA/ANSI NGV 5.1, manufacturer’s installation instructions and Section 413 of the International Fuel Gas Code . The capacity of an RFA shall not exceed 5 cubic feet per minute (0.14 m [3] /min) of natural gas.

  2308.2.4 Vehicle fueling appliance (VFA). Nonresidential fueling appliances shall be listed and installed in accordance with the installation requirements of CSA/ANSI NGV 5.2, manufacturer’s installation instructions and the requirements of Section 413 of the International Fuel Gas Code for VFAs. The capacity of the VFA shall not exceed 10 cubic feet per minute (0.28 m [3] /min) of natural

  gas.

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  MOTOR FUEL-DISPENSING FACILITIES AND REPAIR GARAGES

  2308.3 Location of dispensing operations and equipment. Compression, storage and dispensing equipment shall be located above ground, outdoors.

  Exceptions:

  1. Compression, storage or dispensing equipment shall be allowed in buildings of noncombustible construction, as set forth in the California Building Code, that are unenclosed for three-quarters or more of the perimeter.
  2. Compression, storage and dispensing equipment shall be allowed indoors or in vaults in accordance with Chapter 53.

  2308.3.1 Location on property. In addition to the requirements of Section 2303.1, compression, storage and dispensing equipment not located in vaults complying with Chapter 53 shall be installed as follows:

  1. Not beneath power lines.
  2. Ten feet (3048 mm) or more from the nearest building or lot line that could be built on, public street, sidewalk or source of ignition.

  Exception: Dispensing equipment need not be separated from canopies that are constructed in accordance with the California Building Code and that provide weather protection for the dispensing equipment. 3. Twenty-five feet (7620 mm) or more from the nearest rail of any railroad track and 50 feet (15 240 mm) or more from the nearest rail of any railroad main track or any railroad or transit line where power for train propulsion is provided by an outside electrical source, such as third rail or overhead catenary. 4. Fifty feet (15 240 mm) or more from the vertical plane below the nearest overhead wire of a trolley bus line.

  2308.4 Private fueling of motor vehicles. Self-service CNG-dispensing systems, including key, code and card lock dispensing systems, shall be limited to the filling of permanently mounted fuel containers on CNG-powered vehicles.

• CMC § 204.0 Medium relevance — show source text

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  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 § 9.1 Medium relevance — show source text

  SHUTOFF VALVE APPLICATION	STANDARDS
  Appliance shutoff valve up to1_/_2 psi	CSA/ANSI Z21.15/CSA 9.1
  Appliance shutoff valve up to1_/_2 psi	ASME B16.44
  Appliance shutoff valve up to1_/_2 psi	ASME B16.33 marked 125 G
  Appliance shutoff valve up to1_/_2 psi	CSA/ANSI LC 4/CSA 6.32
  Valve up to1_/_2 psi	ASME B16.44
  Valve up to1_/_2 psi	ASME B16.33 marked 125 G
  Valve up to1_/_2 psi	CSA/ANSI LC 4/CSA 6.32
  Valve up to 2 psi	ASME B16.44 labeled 2G
  Valve up to 2 psi	ASME B16.33 marked 125 G
  Valve up to 2 psi	CSA/ANSI LC 4/CSA 6.32 with ANSI/ASME B16.44 labeled 2G or labeled 5G
  Valve up to 2 psi	CSA/ANSI LC 4/CSA 6.32 with ANSI/ASME B16.33 marked 125 G
  Valve up to 5 psi	ASME B16.44 labeled 5G
  Valve up to 5 psi	ASME B16.33
  Valve up to 5 psi	CSA/ANSI LC 4/CSA 6.32 with ANSI/ASME B16.44 marked 5G
  Valve up to 5 psi	CSA/ANSI LC 4/CSA 6.32 with ANSI/ASME B16.33 marked 125 G
  Valve up to 125 psi	ASME B16.33 marked 125 G
  Valve up to 125 psi	CSA/ANSI LC 4/CSA 6.32 with ASME B16.33 marked 125 G

  For SI Units: 1 pound-force per square inch = 6.8947 kPa

  1308.13 Expansion and Flexibility. Piping systems shall be designed to prevent failure from thermal expansion or contraction. [NFPA 54:5.13.1]

• CMC § 12.6.1.3 Medium relevance — show source text

  (1) Approved clay flue lining

  (2) A chimney lining system listed and labeled in accordance with UL 1777

  (3) Other approved material that resists corrosion, erosion, softening, or cracking from vent gases at temperatures up to 1800°F (982°C)

  Exception: Masonry chimney flues lined with a chimney lining system specifically listed for use with listed appliances with draft hoods, Category I appliances, and other appliances listed for use with Type B vents shall be permitted. The liner shall be installed in accordance with the liner manufacturer’s installation instructions. A permanent identifying label shall be attached at the point where the connection is to be made to the liner. The label shall read “This chimney liner is for appliances that burn gas only. Do not connect to solid or liquid fuel-burning appliances or incinerators.” [NFPA 54:12.6.1.3] 509.5.4 Termination. A chimney for residential-type or low-heat appliances shall extend at least 3 feet (914 mm) above the highest point where it passes through a roof of a building and at least 2 feet (610 mm) higher than any portion of a building within a horizontal distance of 10 feet (3048 mm). [NFPA 54:12.6.2.1] (See Figure 509.5.4) 509.5.4.1 Medium-Heat Gas Appliances. A chimney for medium-heat appliances shall extend at least 10 feet (3048 mm) higher than any portion of any building within 25 feet (7620 mm). [NFPA 54:12.6.2.2] 509.5.4.2 Chimney Height. A chimney shall extend at least 5 feet (1524 mm) above the highest connected appliance draft hood outlet or flue collar.

  [NFPA 54:12.6.2.3]

  509.5.4.3 Decorative Shrouds. Decorative

  shrouds shall not be installed at the termination of factory-built chimneys except where such shrouds are listed and labeled for use with the specific factory-built chimney system and are installed in accordance with the manufacturer’s installation instructions. [NFPA 54:12.6.2.4] 509.5.5 Size of Chimneys. The effective area of a chimney venting system serving listed appliances with draft hoods, Category I appliances, and other appliances listed for use with Type B vents shall be in accordance with one of the following methods:

  (1) Those listed in Section 510.0.

  (2) The effective areas of the vent connector and chimney flue of a venting system serving a single appliance with a draft hood shall be not less than the area of the appliance flue collar or draft hood outlet or greater than seven times the draft hood outlet area.

  (3) The effective area of the chimney flue of a venting system serving two appliances with draft hoods shall be not less than the area of the larger draft hood outlet plus 50 percent of the area of the smaller draft hood outlet or greater than seven times the smaller draft hood outlet area.

  (4) Chimney venting systems using mechanical draft shall be sized in accordance with engineering methods.

• CMC § 211.0 Medium relevance — show source text

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  that are listed below
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  Adopt Entire Chapter
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  amended (amended
  sections listed below)
  Adopt only those sections
  that are listed below
  Chapter/Section
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  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 –

  ABS. Acrylonitrile-butadiene-styrene. Accepted Engineering Practice. That which conforms to technical or scientific-based principles, tests, or standards that are accepted by the engineering profession. Accessible. Where applied to a fixture, connection, 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.

• CMC § 802.3.3.3 Medium relevance — show source text

  802.3.3.3 Vent Connectors. Vent connectors

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

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

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

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

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

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

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

  (3) The venting system shall be installed in a conduit or enclosure with joints between the interior of the enclosure and the ceiling space sealed. [NFPA 54:12.4.5.2] 802.4 Type of Venting System to be Used. The type of venting system to be used shall be in accordance with Table 802.4. [NFPA 54:12.5.1]

  802.4.1 Plastic Piping. Where plastic piping is used to vent an appliance, the appliance shall be listed for use with such venting materials and the appliance manufacturer’s installation instructions shall identify the specific plastic piping material. The plastic pipe venting materials shall be labeled in accordance with the product standards specified by the appliance manufacturer or shall be listed and labeled in accordance with UL 1738. [NFPA 54:12.5.2]

  802.4.2 Plastic Vent Joints. Plastic pipe and fittings used to vent appliances shall be installed in accordance with the appliance manufacturer’s installation instructions. Plastic pipe venting materials listed and labeled in accordance with UL 1738 shall be installed in accordance

  with the vent manufacturer’s installation instructions. Where primer is required, it shall be of a contrasting color.

  [NFPA 54:12.5.3]

  802.4.3 Special Gas Vents. Special gas vents shall be listed and labeled in accordance with UL 1738 and installed in accordance with the special gas vent manufacturer’s installation instructions. [NFPA 54:12.5.4]

• CMC § 403.3.1.1 Medium relevance — show source text

  Spaces in which such systems are located shall be considered to be kitchens and shall be ventilated in accordance with Table 403.3.1.1 of the California Mechanical Code . For the purpose of determining the floor area required to be ventilated, each individual appliance shall be considered as occupying not less than 100 square feet (9.3 m [2] ). 3. Where cooking appliances are equipped with integral down-draft exhaust systems and such appliances and exhaust systems are listed and labeled for the application in accordance with NFPA 96, a hood shall not be required at or above them.

  4. A Type I hood shall not be required for an electric cooking appliance where an approved testing agency provides documentation that the appliance effluent contains 5 mg/m [3] or less of grease when tested at an exhaust flow rate of 500 cfm (0.236 m [3] /s) in accordance with UL 710B.

  606.3 Operations and maintenance. Commercial cooking systems shall be operated, inspected and maintained in accordance with Sections 606.3.1 through 606.3.4.

  606.3.1 Ventilation system. The ventilation system in connection with hoods shall be operated at the required rate of air movement, and grease filters listed and labeled in accordance with UL 1046 shall be in place where equipment under a kitchen grease hood is used.

  606.3.2 Grease extractors. Where grease extractors are installed, they shall be operated when the commercial-type cooking equipment is used.

  606.3.3 Cleaning. Hoods, grease-removal devices, fans, ducts and other appurtenances shall be cleaned at intervals as required by Sections 606.3.3.1 through 606.3.3.3.

  606.3.3.1 Inspection. Hoods, grease-removal devices, fans, ducts and other appurtenances shall be inspected at intervals specified in Table 606.3.3.1 or as approved by the fire code official. Inspections shall be completed by qualified individuals.

  TABLE 606.3.3.1—COMMERCIAL COOKING SYSTEM INSPECTION FREQUENCY	Col2
  TYPE OF COOKING OPERATIONS	FREQUENCY OF INSPECTION
  High-volume cooking operations such as 24-hour cooking, charbroiling or wok cooking	3 months
  Low-volume cooking operations such as places of religious worship, seasonal businesses and senior centers	12 months
  Cooking operations utilizing solid fuel-burning cooking appliances	1 month
  All other cooking operations	6 months

  606.3.3.2 Grease accumulation. If during the inspection it is found that hoods, grease-removal devices, fans, ducts or other appurtenances have an accumulation of grease, such components shall be cleaned in accordance with ANSI/IKECA C10.

  606.3.3.3 Records. Records for inspections shall state the individual and company performing the inspection, a description of the inspection and when the inspection took place. Records for cleanings shall state the individual and company performing the cleaning and when the cleaning took place. Such records shall be completed after each inspection or cleaning and maintained.

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  on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

  BUILDING SERVICES AND SYSTEMS

• CMC § 3.3.3 Medium relevance — show source text

  [NFPA 54:3.3.3] Appliance. A device that utilizes fuel or electricity as an energy source to produce light, heat, power, refrigeration, or air conditioning. This definition also includes vented decorative appliances and electric storage or tankless water heaters. Appliance, Low-Heat. A fuel-burning appliance that produces a continuous flue gas temperature, at the point of entrance to the flue, of not more than 1000°F (538°C). Appliance, Medium-Heat. A fuel-burning appliance that produces a continuous flue gas temperature, at the point of entrance to the flue, of more than 1000°F (538°C) and less than 2000°F (1093°C). Appliance Categorized Vent Diameter/Area. The minimum vent diameter/area permissible for Category I appliances to maintain a nonpositive vent static pressure when tested in accordance with nationally recognized standards.

  [NFPA 54:3.3.5] Appliance Fuel Connector. An assembly of listed semirigid or flexible tubing and fittings to carry fuel between a fuel-piping outlet and a fuel-burning appliance. Approved. Acceptable to the Authority Having Jurisdiction. Exception: [HCD 1 & HCD 2] “Approved” means meeting the approval of the Enforcing Agency, except as otherwise pro- vided by law, when used in connection with any system, mate- rial, type of construction, fixture or appliance as the result of investigations and tests conducted by the agency, or by rea- son of accepted principles or tests by national authorities, or technical, health, or scientific organizations or agencies.

  Notes:

  1. See Health and Safety Code Section 17920 for “Approved” as applied to residential construction and buildings or structures accessory thereto as referenced in Section 1.8.2.

  2. See Health and Safety Code Section 17921.1 for “Approved” as applied to the use of the hotplates in res- idential construction as referenced in Section 1.8.2.

  3. See Health and Safety Code 19966 for “Approved” as applied to Factory-Built Housing as referenced in Sec- tion 1.8.3.2.5.

  4. See Health and Safety Code Section 18201 for “Approved” as applied to Mobilehome Parks as refer- enced in Section 1.8.2.

  5. See Health and Safety Code Section 18862.1 for “Approved” as applied to Special Occupancy Parks as referenced in Section 1.8.2. Approved Testing Agency. An organization primarily established for purposes of testing to approved standards and approved by the Authority Having Jurisdiction.

  [HCD 1 & HCD 2] “Approved Testing Agency” is any agency which is determined by the enforcing agency, except

  2025 CALIFORNIA PLUMBING CODE 31

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  DEFINITIONS

  as otherwise provided by statute, to have adequate personnel and expertise to carry out the testing of systems, materials, and construction fixtures or appliances. Area Drain. A receptor designed to collect surface or storm water from an open area. **Aspirator.

• CMC § 25.4 Medium relevance — show source text

  FIGURE R1003.20—CHIMNEY CRICKET

  AIRSPACE

  ROOF LINE

  For SI: 1 inch = 25.4 mm.

  FLUE LINER	Col2	Col3	Col4	Col5
  1 IN. AIRS	1 IN. AIRS	1 IN. AIRS	1 IN. AIRS	1 IN. AIRS
  W	W	W	W	W

  2025 CALIFORNIA RESIDENTIAL CODE 10-11

  on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

  �

  CHIMNEYS AND FIREPLACES

  SECTION R1004—FACTORY-BUILT FIREPLACES

  R1004.1 General. Factory-built fireplaces shall be listed and labeled and shall be installed in accordance with the conditions of the listing. Factory-built fireplaces shall be tested in accordance with UL 127.

  R1004.1.1 Factory-built wood burning fireplaces. Factory-built wood burning fireplaces shall be qualified at the U.S. EPA’s Volun- tary Fireplace Program Phase 2 emissions level and be in accordance with the California Green Building Standards Code, Chapter 4, Division 4.5.

  R1004.2 Hearth extensions. Hearth extensions of approved factory-built fireplaces shall be installed in accordance with the listing of the fireplace. The hearth extension shall be readily distinguishable from the surrounding floor area. Listed and labeled hearth extensions shall comply with UL 1618.

  R1004.3 Decorative shrouds. Decorative shrouds shall not be installed at the termination of chimneys for factory-built fireplaces except where the shrouds are listed and labeled for use with the specific factory-built fireplace system and installed in accordance with the manufacturer’s instructions.

  R1004.5 Gasketed fireplace doors. A gasketed fireplace door shall not be installed on a factory-built fireplace except where the fireplace system has been specifically tested, listed and labeled for such use in accordance with UL 127.

  SECTION R1005—FACTORY-BUILT CHIMNEYS

  R1005.1 Listing. Factory-built chimneys shall be listed and labeled and shall be installed and terminated in accordance with the manufacturer’s installation instructions.

  R1005.2 Decorative shrouds. Decorative shrouds shall not be installed at the termination of factory-built chimneys except where the shrouds are listed and labeled for use with the specific factory-built chimney system and installed in accordance with the manufacturer’s installation instructions.

  R1005.3 Solid-fuel appliances. Factory-built chimneys installed in dwelling units with solid-fuel-burning appliances shall comply with the Type HT requirements of UL 103 and shall be marked “Type HT” and “Residential Type and Building Heating Appliance Chimney.”

  Exception: Chimneys for use with open combustion chamber fireplaces shall comply with the requirements of UL 103 and shall be marked “Residential Type and Building Heating Appliance Chimney.”

  Chimneys for use with open combustion chamber appliances installed in buildings other than dwelling units shall comply with the requirements of UL 103 and shall be marked “Building Heating Appliance Chimney” or “Residential Type and Building Heating Appliance Chimney.”

  R1005.4 Factory-built fireplaces. Chimneys for use with factory-built fireplaces shall comply with the requirements of UL 127.

• CMC § 12.4.5.2 Medium relevance — show source text

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

  (3) The venting system shall be installed in a conduit or enclosure with joints between the interior of the enclosure and the ceiling space sealed. [NFPA 54:12.4.5.2] 802.4 Type of Venting System to be Used. The type of venting system to be used shall be in accordance with Table 802.4. [NFPA 54:12.5.1]

  802.4.1 Plastic Piping. Where plastic piping is used to vent an appliance, the appliance shall be listed for use with such venting materials and the appliance manufacturer’s installation instructions shall identify the specific plastic piping material. The plastic pipe venting materials shall be labeled in accordance with the product standards specified by the appliance manufacturer or shall be listed and labeled in accordance with UL 1738. [NFPA 54:12.5.2]

  802.4.2 Plastic Vent Joints. Plastic pipe and fittings used to vent appliances shall be installed in accordance with the appliance manufacturer’s installation instructions. Plastic pipe venting materials listed and labeled in accordance with UL 1738 shall be installed in accordance

  with the vent manufacturer’s installation instructions. Where primer is required, it shall be of a contrasting color.

  [NFPA 54:12.5.3]

  802.4.3 Special Gas Vents. Special gas vents shall be listed and labeled in accordance with UL 1738 and installed in accordance with the special gas vent manufacturer’s installation instructions. [NFPA 54:12.5.4]

  802.5 Masonry, Metal, and Factory-Built Chimneys. Chimneys shall be installed in accordance with Section 802.5.1 through Section 802.5.3.

  802.5.1 Factory-Built Chimneys. Factory-built chimneys shall be listed in accordance with UL 103, UL 959, or UL 2561. Factory-built chimneys used to vent appliances that operate at positive vent pressure shall be listed for such application. [NFPA 54:12.6.1.1]

  802.5.1.1 Decorative Shrouds. Decorative shrouds addressed in Section 802.5.4.3 shall comply with UL 103 for factory-built residential chimneys, UL 127 for factory-built fireplaces, or UL 1482 for solid-fuel room heaters.

  802.5.2 Metal Chimneys. Metal chimneys shall be built and installed in accordance with NFPA 211. [NFPA 54:12.6.1.2]

  802.5.3 Masonry Chimneys. Masonry chimneys shall be built and installed in accordance with NFPA 211 and lined with one of the following:

  (1) Approved clay flue lining.

  (2) A chimney lining system listed and labeled in accordance with UL 1777.

  (3) Other approved material that resists corrosion, erosion, softening, or cracking from vent gases at temperatures up to 1800°F (982°C).

  Exception: Masonry chimney flues lined with a chimney lining system specifically listed for use with listed appliances with draft hoods, Category I appliances, and

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  CHIMNEYS AND VENTS

• CMC § 503.7.1 Medium relevance — show source text

  ** Heat pumps equipped with internal electric resistance heaters shall have controls that prevent supplemental heater operation where the heating load is capable of being met by the heat pump alone during both steady-state operation and setback recovery. Supplemental heater operation shall be permitted during outdoor coil defrost cycles. Exception: Heat pumps whose minimum efficiency is regulated by U.S. National Appliance Energy Conservation Act (NAECA) and whose ratings are in accordance with the requirements shown in Table E 503.7.1(2) and includes the use of an internal electric resistance heating. [ASHRAE 90.1:6.4.3.5] E 503.4.6.7 Humidification and Dehumidifica- tion Control. Humidification and dehumidification

  control shall be in accordance with Section E 503.4.6.7.1 through Section E 503.4.6.7.3. E 503.4.6.7.1 Dehumidification. Humidistatic controls shall not use mechanical cooling to reduce the humidity below the lower of a dew point of 55°F (12.8°C) or relative humidity of 60 percent in the coldest zone served by the system. Exceptions: (1) Lower humidity shall be permitted when operating mechanical cooling for temperature control.

  (2) Systems serving zones where specific humidity levels are required, such as museums and hospitals, and approved by the Authority Having Jurisdiction or required by accreditation standards, and where humidistatic controls are capable of and configured to maintain a dead band of at least 10 percent relative humidity where no active humidification or dehumidification takes place.

  (3) Systems serving zones where humidity levels are required to be maintained with precision of not more than ±5 percent relative humidity to comply with applicable codes or accreditation standards or as approved by the Authority Having Jurisdiction.

  [ASHRAE 90.1:6.4.3.6.1]

  E 503.4.6.7.2 Humidification. Humidistatic controls shall not use fossil fuel or electricity to produce relative humidity above 30 percent in the warmest zone served by the system.

  Exceptions:

  (1) Systems serving zones where specific humidity levels are required, such as museums and hospitals, and approved by the Authority Having Jurisdiction or required by accreditation standards, and where humidistatic controls are capable of and configured to maintain a dead band of at least 10 percent relative humidity where no active humidification or dehumidification takes place.

  TABLE E 503.4.6.4.2 MAXIMUM DAMPER LEAKAGE [1, 2]

  (cubic foot per minute per square foot) at 1.0 inch water gauge

  [ASHRAE 90.1: TABLE 6.4.3.4.3]

• CMC § 110.2 Medium relevance — show source text

  Compliance with the cooling-only perfor-
  mance is required as defined in Notes b and c of Table 110.2-I.
  f. For liquid source heat recovery chilling packages that have capabilities for heat rejection to a heat recovery condenser and a tower condenser, the COPHR applies to operation
  at full load with 100 percent heat recovery (no tower rejection). Units that only have capabilities for partial heat recovery shall meet the requirements of Table 110.2-D, Water
  Chilling Packages—Minimum Efficiency Requirements.
  g. For heat recovery heating chilling package applications where there is simultaneous cooling and heating, compliance with the heating performance heat recover COPHR is
  only required at one of the four heating AHRI 550/590 (I-P) standard ratings conditions of Low, Medium, Hot-Water 1 or Hot-Water 2. Compliance with the cooling-only perfor-
  mance is required as defined in Notes b and c of Table 110.2-I.
  h. Water-to-water heat pumps with a capacity less than 135,000 Btu/h are included in Table 110.2-B, Heat Pumps—Minimum Efficiency Requirements.
  i. Source leaving liquid temperature.
  1. The cooling evaporator liquid flow rate used for the heating rating for a reverse cycle air-to-water heat pump shall be the flow rate determined during the full-load cool-
  ing rating.
  2. The cooling evaporator liquid flow rate for the simultaneous cooling and heating and heat recovery liquid cooled chilling packages rating shall be the liquid flow rates
  from the cooling operation full-load rating.
  3. For heating-only fluid-to-fluid chiller packages, the evaporator flow rate obtained with an entering liquid temperature of 54°F and a leaving liquid temperature of 44°F
  shall be used.
  j. NA means the requirements are not applicable.|a. The size category is the full-load net refrigeration cooling mode capacity, which is the capacity of the evaporator available for cooling of the thermal load external to the chill-
  ing package.
  b. For air source heat pumps, compliance with both the 47°F and 17°F heating source outdoor air temperature (OAT) rating efficiency is required for heating.
  c. Heating full-load rating conditions are at standard rating conditions defined in AHRI 550/590 (I-P), Table 4, which includes the impact of defrost for air source heating ratings.
  d. For units that operate in both cooling and heating, compliance with both the cooling and heating efficiency is required.
  e. For heat recovery heating chilling package applications where there is simultaneous cooling and heating, compliance with the heating performance heat recover COPHR is
  only required at one of the four heating AHRI 550/590 (I-P) standard ratings conditions of Low, Medium, Hot-Water 1 or Hot-Water 2. Compliance with the cooling-only perfor-
  mance is required as defined in Notes b and c of Table 110.2-I.
  f. For liquid source heat recovery chilling packages that have capabilities for heat rejection to a heat recovery condenser and a tower condenser, the COPHR applies to operation
  at full load with 100 percent heat recovery (no tower rejection). Units that only have capabilities for partial heat recovery shall meet the requirements of Table 110.2-D, Water
  Chilling Packages—Minimum Efficiency Requirements.
  g.

• CMC § 406.2.2 Medium relevance — show source text

  406.2.2 Clear height. The clear height of each floor level in vehicle and pedestrian traffic areas shall be not less than 7 feet (2134 mm). Canopies under which fuels are dispensed shall have a clear height in accordance with Section 406.7.2. [DSA-AC, HCD 1-AC] The clear height of vehicle and pedestrian areas required to be accessible shall comply with Chapter 11A or 11B, as applicable.

  Exception: A lower clear height is permitted for a parking tier in mechanical-access open parking garages where approved by the building official.

  [BE] 406.2.3 Accessible parking spaces. Where parking is provided, accessible parking spaces, access aisles and vehicular routes serving accessible parking shall be provided in accordance with Chapter 11A or Chapter 11B, as applicable.

  406.2.4 Floor surfaces. Floor surfaces shall be of concrete or similar approved noncombustible and nonabsorbent materials. The area of floor used for the parking of automobiles or other vehicles shall be sloped to facilitate the movement of liquids to a drain or toward the main vehicle entry doorway. The surface of vehicle fueling pads in motor fuel-dispensing facilities shall be in accordance with Section 406.7.1.

  Exceptions:

  1. Asphalt parking surfaces shall be permitted at ground level for public parking garages and private carports.
  2. Slip-resistant, nonabsorbent, interior floor finishes having a critical radiant flux not more than 0.45 W/cm [2], as determined by ASTM E648 or NFPA 253, shall be permitted in repair garages.

  406.2.5 Sleeping rooms. Openings between a motor vehicle-related occupancy and a room used for sleeping purposes shall not be permitted.

  406.2.6 Fuel dispensing. The dispensing of fuel shall only be permitted in motor fuel-dispensing facilities in accordance with Section 406.7.

  406.2.7 Electric vehicle charging stations and systems. Where provided, electric vehicle charging systems shall be installed in accordance with the California Electrical Code and the California Green Building Standards Code . Electric vehicle charging system equipment shall be listed and labeled in accordance with UL 2202. Electric vehicle supply equipment shall be listed and labeled in accordance with UL 2594. Accessibility to electric vehicle charging stations shall be provided in accordance with Chapters 11A and/or 11B.

  406.2.8 Mixed occupancies and uses. Mixed uses shall be allowed in the same building as public parking garages and repair garages in accordance with Section 508.1. Mixed uses in the same building as an open parking garage are subject to Sections 402.4.2.3, 406.5.11, 508.1, 510.3, 510.4 and 510.7.

  406.2.9 Equipment and appliances. Equipment and appliances shall be installed in accordance with Sections 406.2.9.1 through 406.2.9.3 and the California Mechanical Code, California Plumbing Code and California Electrical Code.

• CMC § 201.0 Medium relevance — show source text

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

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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.

  Accessory Dwelling Unit. [HCD 1 & HCD 2] An attached or detached residential dwelling unit that provides complete independent living facilities for one or more persons and is located on a lot with a proposed or existing primary residence. Accessory dwelling units shall include permanent provisions for living, sleeping, eating, cooking, and sanitation on the same parcel as the single-family or multifamily dwelling is or will be situated. (See Government Code Section 65852.2.)

  Air, Class 1. Air with low contaminant concentration, low sensory-irritation intensity, and inoffensive odor. [ASHRAE 62.1:5.18.1]

  Air, Class 2. Air with moderate contaminant concentration, mild sensory-irritation intensity, or mildly offensive odors. Class 2 air also includes air that is not necessarily harmful or objectionable, but that is inappropriate for transfer or recirculation to spaces used for different purposes. [ASHRAE 62.1:5.18.1]

  Air, Class 3. Air with significant contaminant concentration, significant sensory-irritation intensity, or offensive odor.

  [ASHRAE 62.1:5.18.1]

  Air, Class 4. Air with highly objectionable fumes or gases or with potentially dangerous particles, bioaerosols, or gases, at concentrations high enough to be considered as harmful.

  [ASHRAE 62.1:5.18.1]

  Air, Combustion. See Combustion Air.

  Air, Conditioned. Air that has been treated to achieve a desired level of temperature, humidity, or cleanliness.

• CMC § 605.7.6 Medium relevance — show source text

  605.7.6 Flue-fed incinerators in Group I-2. In Group I-2 occupancies, the continued use of existing flue-fed incinerators is prohibited.

  605.7.7 Incinerator inspections in Group I-2. Incinerators in Group I-2 occupancies shall be inspected not less than annually in accordance with the manufacturer’s instructions. Inspection records shall be maintained on the premises and made available to the fire code official upon request.

  605.8 Gas meters. Above-ground gas meters, regulators and piping subject to damage shall be protected by a barrier complying with Section 312 or otherwise protected in an approved manner.

  SECTION 606—COMMERCIAL COOKING EQUIPMENT AND SYSTEMS

  [M] 606.1 General. Commercial kitchen exhaust hoods shall comply with the requirements of the California Mechanical Code .

  [M] 606.2 Where required. A Type I hood shall be installed at or above all commercial cooking appliances and domestic cooking appliances used for commercial purposes that produce grease vapors.

  Exceptions:

  1. Factory-built commercial exhaust hoods that are listed and labeled in accordance with UL 710, and installed in accordance with Section 304.1 of the California Mechanical Code, shall not be required to comply with Sections 507.1.5, 507.2.3, 507.2.5, 507.2.8, 507.3.1, 507.3.3, 507.1.6 and 507.2.10 of the California Mechanical Code .

  2. Factory-built commercial cooking recirculating systems that are listed and labeled in accordance with UL 710B, and installed in accordance with Section 304.1 of the California Mechanical Code, shall not be required to comply with Sections 507.1.5, 507.2.3, 507.2.5, 507.2.8, 507.3.1, 507.3.3, 507.1.6 and 507.2.10 of the California Mechanical Code . Spaces in which such systems are located shall be considered to be kitchens and shall be ventilated in accordance with Table 403.3.1.1 of the California Mechanical Code . For the purpose of determining the floor area required to be ventilated, each individual appliance shall be considered as occupying not less than 100 square feet (9.3 m [2] ).

  3. Where cooking appliances are equipped with integral down-draft exhaust systems and such appliances and exhaust systems are listed and labeled for the application in accordance with NFPA 96, a hood shall not be required at or above them.

  4. A Type I hood shall not be required for an electric cooking appliance where an approved testing agency provides documentation that the appliance effluent contains 5 mg/m [3] or less of grease when tested at an exhaust flow rate of 500 cfm (0.236 m [3] /s) in accordance with UL 710B.

  606.3 Operations and maintenance. Commercial cooking systems shall be operated, inspected and maintained in accordance with Sections 606.3.1 through 606.3.4.

  606.3.1 Ventilation system. The ventilation system in connection with hoods shall be operated at the required rate of air movement, and grease filters listed and labeled in accordance with UL 1046 shall be in place where equipment under a kitchen grease hood is used.

• CMC § 2113.11 Medium relevance — show source text

  2113.11 Flue lining (material). Masonry chimneys shall be lined. The lining material shall be appropriate for the type of appliance connected, according to the terms of the appliance listing and the manufacturer’s instructions.

  2113.11.1 Residential-type appliances (general). Flue lining systems shall comply with one of the following:

  1. Clay flue lining complying with the requirements of ASTM C315.
  2. Listed chimney lining systems complying with UL 1777.
  3. Factory-built chimneys or chimney units listed for installation within masonry chimneys.
  4. Other approved materials that will resist corrosion, erosion, softening or cracking from flue gases and condensate at temperatures up to 1,800°F (982°C).

  2113.11.1.1 Flue linings for specific appliances. Flue linings other than those covered in Section 2113.11.1 intended for use with specific appliances shall comply with Sections 2113.11.1.2 through 2113.11.1.4, 2113.11.2 and 2113.11.3.

  2113.11.1.2 Gas appliances. Flue lining systems for gas appliances shall be in accordance with the California Mechanical Code .

  2113.11.1.3 Pellet fuel-burning appliances. Flue lining and vent systems for use in masonry chimneys with pellet fuel-burning appliances shall be limited to flue lining systems complying with Section 2113.11.1 and pellet vents listed for installation within masonry chimneys (see Section 2113.11.1.5 for marking).

  2113.11.1.4 Oil-fired appliances approved for use with L-vent. Flue lining and vent systems for use in masonry chimneys with oil-fired appliances approved for use with Type L vent shall be limited to flue lining systems complying with Section 2113.11.1 and listed chimney liners complying with UL 641 (see Section 2113.11.1.5 for marking).

  2113.11.1.5 Notice of usage. When a flue is relined with a material not complying with Section 2113.11.1, the chimney shall be plainly and permanently identified by a label attached to a wall, ceiling or other conspicuous location adjacent to where the connector enters the chimney. The label shall include the following message or equivalent language: “This chimney is for use only with (type or category of appliance) that burns (type of fuel). Do not connect other types of appliances.”

  2113.11.2 Concrete and masonry chimneys for medium-heat appliances. Concrete and masonry chimneys for medium-heat appliances shall comply with Sections 2113.11.2.1 through 2113.11.2.5.

  2113.11.2.1 Construction. Chimneys for medium-heat appliances shall be constructed of solid masonry units or of concrete with walls not less than 8 inches (203 mm) thick, or with stone masonry not less than 12 inches (305 mm) thick.