CMC · California Mechanical Code
What rules govern LP‑gas facilities and avoiding strain on gas piping?
Homeowner summary: Propane equipment must be installed to NFPA 58 and the California Fire Code (per CMC §303.7); don’t put propane appliances in pits or basements where gas could collect unless you have an approved removal system (§303.7.1), and always support appliances so the gas piping and connectors don’t bear the load (§303.9).
Last reviewed: July 6, 2026
What the code requires — 2-4 sentences
Liquefied Petroleum Gas (LP‑Gas) facilities must be installed to the nationally accepted LP‑gas standard and the State fire code — the CMC requires installation in accordance with NFPA 58 and the California Fire Code (see § 303.7). Appliances fueled by LP‑gas must not be located in pits or basements where heavier‑than‑air gas can collect unless an approved means to remove unburned gas is provided (see § 303.7.1). Separately, the CMC requires that appliances be supported and connected so as not to exert undue strain on gas piping or connections (see § 303.9) .
The single most important practical rule: install LP‑gas equipment per NFPA 58 and the California Fire Code, keep LP appliances out of places where propane can pool, and support appliances so gas connectors carry no undue load.
Requirements in detail
Scope & applicable standards
- LP‑Gas facilities (tanks, containers, valves, regulators, meters and related appurtenances) are governed by the LP‑Gas chapter and must be installed in accordance with NFPA 58 and the California Fire Code as stated in § 303.7. This is the controlling reference for design, equipment acceptance, and many siting requirements.
Location & siting of LP‑gas appliances
- The CMC explicitly prohibits installing LP‑gas appliances in a pit or basement or similar low point where heavier‑than‑air gas (like propane) might collect — § 303.7.1.
- Such an installation is only allowed if the location is provided with an approved means for removal of unburned gas (i.e., engineered ventilation or active removal approved by the AHJ). § 303.7.1 is the basis for that limitation.
Support, connections, and avoiding strain
- Appliances must be supported and connected to the piping so as not to exert undue strain on the connections — that is the entirety of § 303.9. Practically this means supports, hangers, platforms, or brackets must carry appliance weight and resist imposed forces; the gas connector (including flexible connectors) must not be relied on to support the appliance or to resist stresses that might loosen fittings or tear joints.
- The code language is short and performance‑based; it requires installation practices that prevent mechanical stress on piping connections rather than specifying a single hardware detail. Use manufacturer instructions and accepted engineering practice to demonstrate compliance.
Inspection, coordination with fire code and NFPA 58
- The CMC points installers to NFPA 58 and the California Fire Code for LP‑gas equipment specifics (container spacing, size limits, dispenser requirements, overfill prevention, etc.). For LP‑gas facility specifics and large‑capacity installations, consult those referenced documents and coordinate with the Authority Having Jurisdiction (fire code official). § 303.7 ties the CMC obligation to those standards.
Decision table — quick reference
| Decision dimension / question | What the code requires or action | Code Reference |
|---|---|---|
| Applicable standard for LP‑Gas facilities | Install per NFPA 58 and the California Fire Code | § 303.7 |
| Can an LP‑gas appliance be in a pit or basement? | No where heavier‑than‑air gas might collect — allowed only with an approved means for removal of unburned gas | § 303.7.1 |
| How must appliances connect to piping? | Supported and connected so as not to exert undue strain on connections; use supports, anchors, platforms as needed | § 303.9 |
| What is an LP‑Gas facility (definition)? | Includes tanks, containers, container valves, regulating equipment, meters, appurtenances for storage and supply | Defined in the CMC index and definitions (LP‑Gas Facilities) (see definition) |
Exceptions & special cases
- The text of § 303.7.1 provides the narrow allowance: an LP‑gas appliance may be installed in an above‑grade under‑floor space or basement only if that location is provided with an approved means for removal of unburned gas. That is an exceptional path and requires AHJ approval and design to NFPA/Fire Code standards.
- The CMC does not reprint all technical LP‑gas container, dispenser, or piping details — for those, the code directs you to NFPA 58 and the California Fire Code. Where the CMC is silent on device‑level details, NFPA 58/CFC or the appliance manufacturer’s instructions control as required by § 303.7.
Common mistakes
- Relying on the flexible connector to support an appliance (weight or lateral loads). The connector must not be the support — provide a bracket, platform or other means so the connector sees no undue strain (§ 303.9).
- Installing propane appliances in low points (pits, basements) without an approved ventilation/removal method — this violates § 303.7.1.
- Treating the CMC requirement for LP‑gas as standalone: you must verify the detailed LP‑gas requirements in NFPA 58 and the California Fire Code as required by § 303.7. Skipping that coordination is a frequent oversight.
Worked example — rooftop make‑up-air heater vs basement water heater (concrete actions)
Scenario: You are installing an LP‑gas‑fired make‑up‑air heater on a rooftop and a propane water heater in a below‑grade utility room.
Rooftop heater: provide a structural platform or roof curb that supports the heater weight and resists wind/seismic loads so the gas connector does not carry the load. Secure the heater to the platform per manufacturer instructions and provide service access. This approach implements § 303.9 — support so the connector is not under undue strain. Cite: § 303.9.
Basement water heater (below grade): do not install the LP‑gas‑fired appliance in the basement if propane vapor could accumulate there. The CMC’s § 303.7.1 requires that such appliances not be in pits/basements unless the location has an approved means for removal of unburned gas. Options: relocate appliance outdoors or provide engineered continuous ventilation/venting approved by AHJ (and follow NFPA 58 / CFC requirements). Cite: § 303.7.1 and § 303.7.
(Those are direct applications of the CMC language: support to avoid undue strain — § 303.9 — and prohibition of low‑point installations without removal means — § 303.7.1.)
Common compliance steps (practical checklist)
- Confirm LP‑gas equipment and piping design follow NFPA 58 and the California Fire Code as required by § 303.7.
- At each appliance: ensure a load support (platform, bracket, post) that carries vertical and lateral loads; confirm flexible connectors are only for movement tolerance, not for support (§ 303.9).
- Prevent placing LP‑gas appliances in pits/basements unless an AHJ‑approved removal/ventilation scheme is provided (§ 303.7.1).
Related provisions (CMC & cross‑references)
- § 303.7 — Liquefied Petroleum Gas (LP‑Gas) Facilities (install per NFPA 58 & California Fire Code).
- § 303.7.1 — Liquefied Petroleum Gas (LP‑Gas) Appliances (no pits/basements unless approved removal).
- § 303.9 — Avoiding Strain on Gas Piping (support appliances; avoid undue strain).
- § 303.8 — Appliances on Roofs (clearance, support, access — relevant when rooftop LP appliances are considered).
- § 1312.11 — Liquefied Petroleum Gas (LP‑Gas) Facilities and Piping (fuel‑gas chapter cross‑reference on LP‑Gas piping).
(If you need the NFPA 58 or California Fire Code text cited above, or the AHJ’s interpretation for an unusual installation, coordinate with the fire code official — the CMC explicitly points to those documents for LP‑gas specifics.)
Code references
Grounded in the retrieved California Mechanical Code — click a citation to read the verbatim passage:
CMC § 507.17 High relevance — show source text
507.17 Extra Device or Attachment. No device or attachment shall be installed on any appliance that could in any way impair the combustion of gas. [NFPA 54:9.1.15] 507.18 Addition to Existing System. When additional appliances are being connected to a gas piping system, the existing piping shall be checked to determine whether it has adequate capacity. If the capacity of the system is determined to be inadequate for the additional appliances, the existing system shall be enlarged as required, or separate gas piping of adequate capacity shall be provided. [NFPA 54:5.1.2] 507.19 Avoiding Strain on Gas Piping. Appliances shall be supported and connected to the piping so as not to exert undue strain on the connections. [NFPA 54:9.1.16] 507.20 Gas Appliance Pressure Regulators. Where the gas supply pressure is higher than that at which the appliance is designed to operate or varies beyond the design pressure limits of the appliance, a gas appliance pressure regulator listed in accordance with CSA/ANSI Z21.18/CSA 6.3 shall be installed. [NFPA 54:9.1.17] 507.21 Bleed Lines for Diaphragm-Type Valves. Bleed lines shall comply with the following requirements:
(1) Diaphragm-type valves shall be equipped to convey bleed gas to the outdoors or into the combustion chamber adjacent to a continuous pilot.
(2) In the case of bleed lines leading outdoors, means shall be employed to prevent water from entering this piping and also to prevent blockage of vents by insects and foreign matter.
(3) Bleed lines shall not terminate in the appliance flue or exhaust system.
(4) In the case of bleed lines entering the combustion chamber, the bleed line shall be located so the bleed gas is readily ignited by the pilot and the heat liberated thereby does not adversely affect the normal operation of the safety shutoff system. The terminus of the bleed line shall be securely held in a fixed position relative to the pilot. For manufactured gas, the need for a flame arrester in the bleed line piping shall be determined.
(5) A bleed line(s) from a diaphragm-type valve and a vent line(s) from an appliance pressure regulator shall not be connected to a common manifold terminating in a com
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WATER HEATERS
508.2 Installation of Appliances on Roofs. Appliances shall be installed in accordance with the manufacturer’s installation instructions. [NFPA 54:9.4.2.1] 508.2.1 Edge of Roof Clearance. Appliances shall be installed on a well-drained surface of the roof. At least 6 feet (1829 mm) of clearance shall be available between any part of the appliance and the edge of a roof or similar hazard, or rigidly fixed rails, guards, parapets, or other building structures at least 42 inches (1067 mm) in height shall be provided on the exposed side. [NFPA 54:9.4.2.2]
508.2.1.1 Guards and Rails. Guards or rails shall be required where the following exist:
CMC § 303.7 High relevance — show source text
303.7 Liquefied Petroleum Gas (LP-Gas) Facilities . . . . . . . . . . . . . . 53
303.8 Appliances on Roofs. . . . . . . . . . . . 53
303.9 Avoiding Strain on Gas Piping . . . . 53
303.10 Clearance to Combustible
Materials . . . . . . . . . . . . . . . . . . . . . 53
303.11 Installation in Commercial
Garages . . . . . . . . . . . . . . . . . . . . . 54
303.12 Installation in Aircraft Hangars . . . . 54
304.0 Accessibility for Service . . . . . . . . . 54
304.1 General. . . . . . . . . . . . . . . . . . . . . . 54
304.2 Sloped Roof . . . . . . . . . . . . . . . . . . 54
304.3 Access to Appliances on Roofs . . . 54
304.4 Appliances in Attics and Under-Floor Spaces . . . . . . . . . . . . 54
305.0 Location . . . . . . . . . . . . . . . . . . . . . 55
305.1 Installation in Residential Garages . . 55
305.2 Pit Location. . . . . . . . . . . . . . . . . . . 55
305.3 Flood Hazard Areas . . . . . . . . . . . . 55
305.4 Elevator Shaft . . . . . . . . . . . . . . . . . 55
305.5 Drainage Pan . . . . . . . . . . . . . . . . . 55
305.6 Outdoor Locations . . . . . . . . . . . . . 55
306.0 Automatic Control Devices . . . . . . . 55
306.1 General. . . . . . . . . . . . . . . . . . . . . . 55
306.2 Building Automation Systems . . . . 56
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TABLE OF CONTENTS
307.0 Labeling . . . . . . . . . . . . . . . . . . . . . 56
307.1 Fuel-Burning Appliances . . . . . . . . 56
307.2 Electric Heating Appliances . . . . . . 56
307.3 Heat Pump and Electric Cooling Appliances . . . . . . . . . . . . . . . . . . . 56
307.4 Absorption Units . . . . . . . . . . . . . . . 56
308.0 Improper Location. . . . . . . . . . . . . . 57
308.1 General. . . . . . . . . . . . . . . . . . . . . . 57
309.0 Workmanship . . . . . . . . . . . . . . . . . 57
309.1 Engineering Practices. . . . . . . . . . . 57
309.2 Concealing Imperfections . . . . . . . . 57
309.3 Installation Practices. . . . . . . . . . . . 57
CMC § 1310.5.1 High relevance — show source text
1310.5.1 Pressure Reduction. Where pressure reduction is required in branch connections for compliance with Section 1310.6, such reduction shall take place either inside the chase or immediately adjacent to the outside wall of the chase. Regulator venting and downstream overpressure protection shall comply with Section 1308.6.4 and Section 1308.7. The regulator shall be accessible for service and repair, and vented in accordance with one of the following:
(1) Where the fuel gas is lighter than air, regulators equipped with a vent limiting means shall be permitted to be vented into the chase. Regulators not equipped with a vent limiting means shall be permitted to be vented either directly to the outdoors or to a point within the top 1 foot (305 mm) of the chase.
(2) Where the fuel gas is heavier than air, the regulator vent shall be vented only directly to the outdoors.
[NFPA 54:7.4.1]
1310.5.2 Chase Construction. Chase construction
shall comply with local building codes with respect to fire resistance and protection of horizontal and vertical openings. [NFPA 54:7.4.2]
1310.5.3 Ventilation. A chase shall be ventilated to the
outdoors and only at the top. The opening(s) shall have a minimum free area [in square inches (square meters)] equal to the product of one-half of the maximum pressure in the piping [in pounds per square inch (kilopas
cals)] times the largest nominal diameter of that piping
[in inches (millimeters)], or the cross-sectional area of the chase, whichever is smaller. Where more than one fuel gas piping system is present, the free area for each system shall be calculated and the largest area used.
[NFPA 54:7.4.3]
1310.6 Maximum Operating Pressure in Buildings. The maximum operating pressure for any piping systems located inside buildings shall not exceed 5 psi (34 kPa) unless one or more of the following conditions are met:
(1) The piping joints are welded or brazed.
(2) The piping is joined by fittings listed to CSA/ANSI LC 4/CSA 6.32 and installed according to the manufacturer’s installation instructions.
(3) The piping joints are flanged and all pipe-to-flange connections are made by welding or brazing.
(4) The piping is located in a ventilated chase or otherwise enclosed for protection against accidental gas accumulation.
(5) The piping is located inside buildings or separate areas of buildings used exclusively for one of the following:
(a) Industrial processing or heating
(b) Research
(c) Warehousing
(d) Boiler or mechanical rooms
(6) The piping is a temporary installation for buildings under construction.
(7) The piping serves appliances or equipment used for agricultural purposes.
(8) The piping system is an LP-Gas piping system with an operating pressure greater than 20 psi (138 kPa) and complies with NFPA 58. [NFPA 54:5.4.4]
1310.6.1 LP-Gas Systems Operating Below -5°F (-21°C). LP-Gas systems designed to operate below 5°F (-21°C) or with butane or a propane-butane mix shall be designed to either accommodate liquid LP-Gas or to prevent LP-Gas vapor from condensing back into a liquid. [NFPA 54:5.4.5]
CMC § 301.1 High relevance — show source text
301.1 Applicability. . . . . . . . . . . . . . . . . . . 51
301.2 Approval . . . . . . . . . . . . . . . . . . . . . 51
301.3 Design of Equipment . . . . . . . . . . . 51
301.4 Electrical Connections . . . . . . . . . . 51
301.5 Oil-Burning Appliances . . . . . . . . . . 51
301.6 Personnel Protection . . . . . . . . . . . 51
301.7 OSHPD 1R . . . . . . . . . . . . . . . . . . . 51
302.0 Materials – Standards and
Alternates . . . . . . . . . . . . . . . . . . . . 51
302.1 Minimum Standards . . . . . . . . . . . . 51
302.2 Alternate Materials and Methods
of Construction Equivalency . . . . . . 51
302.3 Alternative Engineered Design. . . . 52
303.0 Installation . . . . . . . . . . . . . . . . . . . 52
303.1 Listed Appliances . . . . . . . . . . . . . . 52
303.2 Closet or Alcove Installations . . . . . 52
303.3 Unlisted Appliances . . . . . . . . . . . . 52
303.4 Anchorage of Appliances . . . . . . . . 52
303.5 Restraining Device . . . . . . . . . . . . . 53
303.6 Identification of Equipment . . . . . . . 53
303.7 Liquefied Petroleum Gas (LP-Gas) Facilities . . . . . . . . . . . . . . 53
303.8 Appliances on Roofs. . . . . . . . . . . . 53
303.9 Avoiding Strain on Gas Piping . . . . 53
303.10 Clearance to Combustible
Materials . . . . . . . . . . . . . . . . . . . . . 53
303.11 Installation in Commercial
Garages . . . . . . . . . . . . . . . . . . . . . 54
303.12 Installation in Aircraft Hangars . . . . 54
304.0 Accessibility for Service . . . . . . . . . 54
304.1 General. . . . . . . . . . . . . . . . . . . . . . 54
304.2 Sloped Roof . . . . . . . . . . . . . . . . . . 54
304.3 Access to Appliances on Roofs . . . 54
304.4 Appliances in Attics and Under-Floor Spaces . . . . . . . . . . . . 54
305.0 Location . . . . . . . . . . . . . . . . . . . . . 55
305.1 Installation in Residential Garages . . 55
305.2 Pit Location. . . . . . . . . . . . . . . . . . . 55
305.3 Flood Hazard Areas . . . . . . . . . . . . 55
305.4 Elevator Shaft . . . . . . . . . . . . . . . . . 55
CMC § 507.3 High relevance — show source text
507.3 Appliance Support . . . . . . . . . . . . .88
507.4 Ground Support . . . . . . . . . . . . . . .88
507.5 Drainage Pan . . . . . . . . . . . . . . . . .88
507.6 Added or Converted
Equipment or Appliances . . . . . . . .88
507.7 Type of Gas(es) . . . . . . . . . . . . . . .88
507.8 Safety Shutoff Devices for Unlisted LP-Gas Appliance Used Indoors . . . . . . . . . . . . . . . . .89
507.9 Use of Air or Oxygen Under Pressure . . . . . . . . . . . . . . . . . . . . .89
507.10 Protection of Gas Appliances from Fumes or Gases other
than Products of Combustion . . . . .89
507.11 Process Air . . . . . . . . . . . . . . . . . . .89
507.12 Flammable Vapors . . . . . . . . . . . . .89
507.13 Installation in Residential Garages . . . . . . . . . . . . . . . . . . . . .89
507.14 Installation in Commercial Garages . . . . . . . . . . . . . . . . . . . . .89
507.15 Installation in Aircraft Hangars . . . .89
507.16 Venting of Flue Gases . . . . . . . . . .89
507.17 Extra Device or Attachment . . . . . .89
507.18 Addition to Existing System . . . . . .89
507.19 Avoiding Strain on Gas Piping . . . .89
507.20 Gas Appliance Pressure Regulators . . . . . . . . . . . . . . . . . . .89
507.21 Bleed Lines for Diaphragm-Type Valves . . . . . . . . . . . . . . . . . . . . . . .89
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TABLE OF CONTENTS
507.22 Combination of Appliances and Equipment . . . . . . . . . . . . . . . .90
507.23 Installation Instructions . . . . . . . . . .90
507.24 Protection of Outdoor
Appliances . . . . . . . . . . . . . . . . . . .90
507.25 Accessibility for Service . . . . . . . . .90
507.26 Clearance to Combustible
Materials . . . . . . . . . . . . . . . . . . . . .90
508.0 Appliances on Roofs, in Attics or Under-Floor Spaces . . . . . . . . . .90
508.1 General . . . . . . . . . . . . . . . . . . . . . .90
508.2 Installation of Appliances on Roofs . . . . . . . . . . . . . . . . . . . . .90
508.3 Appliances on Roofs . . . . . . . . . . .90
508.4 Appliances in Attics and Under-Floor Spaces . . . . . . . . . . . .91
CMC § 1201.0 High relevance — show source text
1201.0 General.
1201.1 Applicability. The regulations of this chapter shall govern the installation of fuel gas piping in or in connection with a building, structure or within the property lines of premises up to 5 pounds-force per square inch (psi) (34 kPa) for natural gas and 10 psi (69 kPa) for undiluted propane, other than service pipe. Fuel oil piping systems connected to oil- burning equipment shall be installed in accordance with NFPA 31. Fuel oil piping systems connected to internal com- bustion engines and gas turbines shall be installed in accor- dance with NFPA 37.
1202.0 Coverage of Piping System. 1202.1 General. Coverage of piping systems shall extend from the point of delivery to the appliance connections. For other than undiluted liquefied petroleum gas (LP-Gas) systems, the point of delivery shall be the outlet of the service meter assembly or the outlet of the service regulator or service shutoff valve where no meter is provided. For undiluted LP-Gas systems, the point of delivery shall be considered to be the outlet of the final pressure regulator, exclusive of line gas regulators where no meter is installed. Where a meter is installed, the point of delivery shall be the outlet of the meter.
[NFPA 54:1.1.1.1(A)] 1202.2 Piping System Requirements. Requirements for piping systems shall include design, materials, components, fabrication, assembly, installation, testing, inspection, operation, and maintenance. [NFPA 54:1.1.1.1(E)] 1202.3 Applications. This chapter shall not apply to the following items:
(1) Portable LP-Gas appliances and equipment of all types that are not connected to a fixed fuel piping system.
(2) Installation of appliances such as brooders, dehydrators, dryers, and irrigation equipment used for agricultural
purposes.
(3) Raw material (feedstock) applications except for piping to special atmosphere generators.
(4) Oxygen-fuel gas cutting and welding systems.
(5) Industrial gas applications using such gases as acetylene and acetylenic compounds, hydrogen, ammonia, carbon monoxide, oxygen, and nitrogen.
(6) Petroleum refineries, pipeline compressor or pumping stations, loading terminals, compounding plants, refinery tank farms, and natural gas processing plants.
(7) Large integrated chemical plants or portions of such plants where flammable or combustible liquids or gases are produced by chemical reactions or used in chemical reactions.
(8) LP-Gas installations at utility gas plants.
(9) Liquefied natural gas (LNG) installations.
(10)Fuel gas piping in electric utility power plants.
(11)Proprietary items of equipment, apparatus, or instruments such as gas-generating sets, compressors, and calorimeters.
(12)LP-Gas equipment for vaporization, gas mixing, and gas manufacturing.
(13)LP-Gas piping for buildings under construction or renovations that is not to become part of the permanent building piping system—that is, temporary fixed piping for building heat.
(14)Installation of LP-Gas systems for railroad switch heating.
(15)Installation of LP-Gas and compressed natural gas (CNG) systems on vehicles.
(16)Gas piping, meters, gas pressure regulators, and other appurtenances used by the serving gas supplier in distribution of gas, other than undiluted LP-Gas.
CMC § 1201.1 High relevance — show source text
8_||||||||||||||||||||||||| |Adopting Agency
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amended (amended
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1201.1
1211.8||||||||||||||||||||||||| |Adopting Agency
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1201.1
1211.8|||X|||||||||||||||||||||| |Adopting Agency
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amended (amended
sections listed below)
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1201.1
1211.8|||X|||||X|X||||||||||||||||This state agency does not adopt sections identified with the following symbol: The Office of the State Fire Marshal’s adoption of this chapter or individual sections is applicable to structures regulated by other state agencies pursuant to Section 1.11.0.
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CHAPTER 12
FUEL GAS PIPING
1201.0 General.
1201.1 Applicability. The regulations of this chapter shall govern the installation of fuel gas piping in or in connection with a building, structure or within the property lines of premises up to 5 pounds-force per square inch (psi) (34 kPa) for natural gas and 10 psi (69 kPa) for undiluted propane, other than service pipe. Fuel oil piping systems connected to oil- burning equipment shall be installed in accordance with NFPA 31. Fuel oil piping systems connected to internal com- bustion engines and gas turbines shall be installed in accor- dance with NFPA 37.
1202.0 Coverage of Piping System. 1202.1 General. Coverage of piping systems shall extend from the point of delivery to the appliance connections. For other than undiluted liquefied petroleum gas (LP-Gas) systems, the point of delivery shall be the outlet of the service meter assembly or the outlet of the service regulator or service shutoff valve where no meter is provided. For undiluted LP-Gas systems, the point of delivery shall be considered to be the outlet of the final pressure regulator, exclusive of line gas regulators where no meter is installed. Where a meter is installed, the point of delivery shall be the outlet of the meter.
[NFPA 54:1.1.1.1(A)] 1202.2 Piping System Requirements. Requirements for piping systems shall include design, materials, components, fabrication, assembly, installation, testing, inspection, operation, and maintenance. [NFPA 54:1.1.1.1(E)] 1202.3 Applications. This chapter shall not apply to the following items:
CMC § 140.9 High relevance — show source text
9(c)3B Fume Hood Intensive Laboratories 140.9(c)4, Table 140.9-D Function 110.2(a)3, 110.9(b)1D, 110.12(a), 110.12(c)1, 120.8(b)3, 120.8(f)4, 130.1(c)6D, 130.1(f), 141.0(b)2I, 160.5(b)4C, 160.5(b)4F, 180.3(b)4B Function Areas 120.6(g)1, 120.8, 130.1(c)1C, 130.1(c)3B, 130.1(c), 140.6(a)3D, 140.6(c)2AB, 140.6(c)2G, 140.6(c)3A, 140.6(c)3F, 140.6(c)3, 170.2(e)4 Functional Areas 160.5, 130.0(b) Functional Performance Testing 120.8(a)6, 120.8(g) Furnace Installation 150.0(h)4A, 160.3(b)4A Furnace Output 150.0(h)1 Future 240V Use 150.0(n)1, 150.0(t)2, 150.0(u)2, 150.0(v)2, 160.4(a)1B, 160.9(a)2, 160.9(b)2, 160.9(c)
G
Gas Bypass 140.4(e)3B, 170.2(c)4C Cooler efficiency 120.6(a)8H, 120.6(b)5H Cooler pressure 120.6(a)8E-F, 120.6(b)5E-F Fired furnace 110.2(d), Table 110.2-I, Table 110.2-J Furnace 150.0(m)13, 150.1(c)10, 160.3(b)5L, 170.2(c)3B Heater 110.4(b)2 Log 150.0(e), 160.1(f) Or propane 100.2, 150.0(n)1, 150.0(t-v), 150.1(c)8, 150.2(a)1D, 150.2(b)1H, 160.4(a), 160.9, 170.2(d)1C, 170.2(d)3, 180.2(b)3C Service water heating 140.5(c), 141.0(a)2, 170.2(d)3A Supply 160.4(a)4 Water heater 140.5(c), 150.0(n), 170.2(d)3 Gas- and Oil-fired Boilers, Minimum Efficiency Requirements Table 110.2-J Gasket 110.7, 120.1(c)1D, 150.0(a)3, 150.0(k)1C, 150.0(m)12B, 160.1(a)1B, 160.2(b)1B, 160.2(c)1D, 160.5(a)1C Geometry 140.3(a)6E, 141.0(b)3D2, 150.
CMC § 303.8.5 High relevance — show source text
(1) The clearance between the appliance and a roof edge or open end of an equipment platform is less than 6 feet (1829 mm).
(2) The open end of the equipment platform is located more than 30 inches (762 mm) above the roof, floor, or grade below.
Where guards or rails are installed, they shall be constructed so as to prevent the passage of a 21 inch (533 mm) diameter ball, resist the imposed loading conditions, and shall extend not less than 30 inches (762 mm) beyond each side of the equipment or appliance.
Exception: Guards shall not be required where a permanent fall arrest anchorage connector system in accordance with ASSP Z359.1 is installed.
303.8.5 Electrical Power. Appliances requiring an external source of electrical power shall be installed in accordance with the California Electrical Code . [NFPA 54:9.4.2.3]
303.8.6 Platform or Walkway. Where water stands on the roof at the appliance or in the passageways to the appliance, or where the roof is of a design having a water seal, a suitable platform, walkway, or both shall be provided above the water line. Such platform(s) or walkway(s) shall be located adjacent to the appliance and control panels so that the appliance can be safely serviced where water stands on the roof. [NFPA 54:9.4.2.4] 303.9 Avoiding Strain on Gas Piping. Appliances shall be supported and connected to the piping so as not to exert undue strain on the connections. [NFPA 54:9.1.16] 303.10 Clearance to Combustible Materials. Appliances and their vent connectors shall be installed with clearances from combustible material so their operation does not create a hazard to persons or property. Minimum clearances between combustible walls and the back and sides of various conventional types of appliances and their vent connectors are specified in Chapter 8 and Chapter 9, or NFPA 211.
[NFPA 54:9.2.2] Where not provided in this code, listed and unlisted equipment or appliances shall be installed to maintain the required clearances for servicing and to combustible construction in accordance with the listing and the manufacturer’s installation instructions.
303.10.1 Clearance Reduction. Reduced clearances to combustible construction for listed equipment and appliances shall comply with the listing and Table 303.10.1. Where permitted by the manufacturer, and not provided in this code, reduced clearances to combustible construction for unlisted equipment and appliances shall comply with Table 303.10.1. 303.10.1.1 Type I Hood Exhaust System. Reduced clearances for Type I exhaust systems shall be in accordance with Section 507.4.2 through Section 507.4.2.3. Clearances from the duct or the
exhaust fan to the interior surface of enclosures of
combustible construction shall be in accordance with
Section 510.7.3 and clearances shall not be reduced.
303.10.1.2 Product Conveying Ducts. Reduced clearances to combustibles construction for product conveying ducts shall be in accordance with Section 506.10.3 through Section 506.11.6.3.
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CMC § 1315.4 High relevance — show source text
1315.4 Sizing of Piping Sections . . . . . . . 295
1315.5 Engineering Methods . . . . . . . . . . 295
1315.6 Variable Gas Pressures . . . . . . . . 295
Table 1315.2(1) Schedule 40 Metallic Pipe . . . . . . 297
Table 1315.2(2) Schedule 40 Metallic Pipe . . . . . . 298
Table 1315.2(3) Schedule 40 Metallic Pipe . . . . . . 299
Table 1315.2(4) Schedule 40 Metallic Pipe . . . . . . 300
Table 1315.2(5) Schedule 40 Metallic Pipe . . . . . . 301
Table 1315.2(6) Schedule 40 Metallic Pipe . . . . . . 302
Table 1315.2(7) Semi-Rigid Copper Tubing . . . . . . 303
Table 1315.2(8) Semi-Rigid Copper Tubing . . . . . . 304
Table 1315.2(9) Semi-Rigid Copper Tubing . . . . . . 305
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TABLE OF CONTENTS
Table 1315.2(10) Semi-Rigid Copper Tubing . . . . . . 306
Table 1315.2(11) Semi-Rigid Copper Tubing . . . . . . 307
Table 1315.2(12) Semi-Rigid Copper Tubing . . . . . . 308
Table 1315.2(13) Semi-Rigid Copper Tubing . . . . . . 309
Table 1315.2(14) Corrugated Stainless Steel Tubing (CSST) . . . . . . . . . . . . . . . 310
Table 1315.2(15) Corrugated Stainless Steel Tubing (CSST) . . . . . . . . . . . . . . . 311
Table 1315.2(16) Corrugated Stainless Steel Tubing (CSST) . . . . . . . . . . . . . . . 312
Table 1315.2(17) Corrugated Stainless Steel Tubing (CSST) . . . . . . . . . . . . . . . 313
Table 1315.2(18) Corrugated Stainless Steel Tubing (CSST) . . . . . . . . . . . . . . . 314
Table 1315.2(19) Polyethylene Plastic Pipe . . . . . . . 315
Table 1315.2(20) Polyethylene Plastic Pipe . . . . . . . 216
Table 1315.2(21) Polyethylene Plastic Pipe . . . . . . . 317
Table 1315.2(22) Polyethylene Plastic Tubing . . . . . 318
Table 1315.2(23) Polyethylene Plastic Tubing . . . . . 318
Table 1315.2(24) Schedule 40 Metallic Pipe . . . . . . 319
Table 1315.2(25) Schedule 40 Metallic Pipe . . . . . . 320
Table 1315.2(26) Schedule 40 Metallic Pipe . . . . . . 321
CMC § 1313.1 High relevance — show source text
1313.1 Piping Installations . . . . . . . . . . . . 291
1313.2 Test Preparation . . . . . . . . . . . . . . 292
1313.3 Test Pressure . . . . . . . . . . . . . . . . 292
1313.4 Detection of Leaks and Defects . . 292
1313.5 Piping System Leak Test . . . . . . . 292
1313.6 Purging Requirements . . . . . . . . . 292
Table 1313.6.1 Size and Length of Piping. . . . . . . 293
1314.0 Required Gas Supply . . . . . . . . . . 293
1314.1 General. . . . . . . . . . . . . . . . . . . . . 293
1314.2 Volume . . . . . . . . . . . . . . . . . . . . . 293
1314.3 Gas Appliances . . . . . . . . . . . . . . 294
1314.4 Size of Piping Outlets . . . . . . . . . . 294
1315.0 Required Gas Piping Size . . . . . . 294
1315.1 Pipe Sizing Methods. . . . . . . . . . . 294
1315.2 Sizing of Gas Piping Systems . . . 294
1315.3 Sizing Equations. . . . . . . . . . . . . . 294
Table 1315.3 Cr and Y for Natural Gas and
Undiluted Propane at Standard Conditions. . . . . . . . . . . . . . . . . . . 295
1315.4 Sizing of Piping Sections . . . . . . . 295
1315.5 Engineering Methods . . . . . . . . . . 295
1315.6 Variable Gas Pressures . . . . . . . . 295
Table 1315.2(1) Schedule 40 Metallic Pipe . . . . . . 297
Table 1315.2(2) Schedule 40 Metallic Pipe . . . . . . 298
Table 1315.2(3) Schedule 40 Metallic Pipe . . . . . . 299
Table 1315.2(4) Schedule 40 Metallic Pipe . . . . . . 300
Table 1315.2(5) Schedule 40 Metallic Pipe . . . . . . 301
Table 1315.2(6) Schedule 40 Metallic Pipe . . . . . . 302
Table 1315.2(7) Semi-Rigid Copper Tubing . . . . . . 303
Table 1315.2(8) Semi-Rigid Copper Tubing . . . . . . 304
Table 1315.2(9) Semi-Rigid Copper Tubing . . . . . . 305
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TABLE OF CONTENTS
Table 1315.2(10) Semi-Rigid Copper Tubing . . . . . . 306
Table 1315.2(11) Semi-Rigid Copper Tubing . . . . . . 307
Table 1315.2(12) Semi-Rigid Copper Tubing . . . . . . 308
CMC § 608.13.4 High relevance — show source text
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
INDEX
Refrigerant 608.13.4 Treatment system 608.13.5 Ammonium Nitrate 5601.1.5
Defined 202 Ammunition, Small Arms 202, 5606 Storage and handling 105.5.16, 5601.2.1, 5604 Amusement Building, Special (see Special Amusement Building) Amusement Park Structures (Assembly, Group A-5) Defined 202
Annunciator
Defined 202
Appeals, Board of 112, Appendix A Appliances 608.8 Chimneys 605.2.1 Commercial kitchen hoods 606 Cooking 5705.3.3 Fuel-fired 605
Gas piping connection 606.4 Heating 605.5, 4102.1, 5705.3.3 Heat-producing 2301.6 Lighting 5705.3.3 Unsafe 605.2 Applicability (of the code) 102 Approved Agency 202 Additive manufacturing 319.3.2 Combustible decorative materials
807.3 Evaluation report 104.2.3.6.1 Fire-retardant treatment 806.1.4
Inspection report 109.2 Interior floor finish 804.3.2
Labels 805.1.1.3, 805.1.2.3, 805.2.2.3, 805.3.1.3, 805.3.2.3, 805.4.1.3,
805.4.2.3 Smoke control testing 909.18.8.3 Temporary special event structure 3105.5.1 Arc Welding (see Welding and Other Hot Work) Area of Refuge (see Accessible Means of Egress) 202, 1009.6 Array (storage) 3205.8, 3207.4 Defined 202 Array, Closed (storage) 202, 3205.8, 3207.4 Artificial Barricade (see Barricade) Artificial Combustible Vegetation 321 Ash Trays 310.6 Ashes, Hot 305.2 Asphalt (Tar) Kettles 303, 3305.10.1 Asphyxiant Gases 5004.7.1, 5307.1 Assembly Occupancies (Group A) 203 Announcements 403.2.2
Automatic sprinklers 903.2 Candles 308 Cellulose nitrate film 105.5.6, 306 Decorative materials 806, 807 Defined (Occupancy classification) 202 Emergency evacuation drill 405 Employee training 406 Evacuation plans 404 Fire alarm systems 907.2.1 Fire safety plans 404 Furnishings 807.5.1 Interior finish 803
LP-gas installations Chapter 61 Means of egress 1030 Aisles 1018.2, 1030.9, 1030.10,
1030.11
Exit signs 1013.1 Guards 1015.2, 1030.17 Main exit 1030.3
CMC § 12.7 High relevance — show source text
Where mounted on a concrete base, a means shall be provided and installed within [1] / 2 inch (12.7 mm) of the top of the concrete base that will prevent flow from the supply piping in the event that the dispenser is displaced from its mounting. 2. A manual shutoff valve and an excess flow-control check valve shall be located in the liquid line between the pump and the dispenser inlet where the dispensing device is installed at a remote location and is not part of a complete storage and dispensing unit mounted on a common base. 3. An excess flow-control check valve or an emergency shutoff valve shall be installed in or on the dispenser at the point at which the dispenser hose is connected to the liquid piping. 4. A listed automatic-closing type hose nozzle valve with or without a latch-open device shall be provided on island-type dispensers.
2307.6.2 Hoses. Hoses and piping for the dispensing of LP-gas shall be provided with hydrostatic relief valves. The hose length shall not exceed 18 feet (5486 mm). An approved method shall be provided to protect the hose against mechanical damage.
2307.6.3 Emergency breakaway devices. Dispenser hoses shall be equipped with a listed emergency breakaway device designed to retain liquid on both sides of the breakaway point. Where hoses are attached to hose-retrieving mechanisms, the emergency breakaway device shall be located such that the breakaway device activates to protect the dispenser from being displaced.
2307.6.4 Vehicle impact protection. Where installed within 10 feet of vehicle traffic, LP-gas storage containers, pumps and dispensers shall be protected in accordance with Section 2307.5, Item 2.
2307.7 Public fueling of motor vehicles. Self-service LP-gas dispensing systems, including key, code and card lock dispensing systems, shall be limited to the filling of permanently mounted containers providing fuel to the LP-gas powered vehicle.
The requirements for self-service LP-gas dispensing systems shall be in accordance with the following:
The arrangement and operation of the transfer of product into a vehicle shall be in accordance with this section and Chapter 61.
The system shall be provided with an emergency shutoff switch located within 100 feet (30 480 mm) of, but not less than 20 feet (6096 mm) from, dispensers.
The owner of the LP-gas motor fuel-dispensing facility or the owner’s designee shall provide for the safe operation of the system and the training of users.
The dispenser and hose-end valve shall release not more than [1] / 8 fluid ounce (4 cc) of liquid to the atmosphere upon breaking the connection with the fill valve on the vehicle.
Portable fire extinguishers shall be provided in accordance with Section 2305.5.
Warning signs shall be provided in accordance with Section 2305.6.
The area around the dispenser shall be maintained in accordance with Section 2305.7.
2307.8 Overfilling. LP-gas containers shall not be filled with LP-gas in excess of the volume determined using the fixed maximum liquid level gauge installed on the container, the volume determined by the overfilling prevention device installed on the container or the weight determined by the required percentage of the water capacity marked on the container.
SECTION 2308—COMPRESSED NATURAL GAS MOTOR FUEL-DISPENSING FACILITIES
CMC § 25.4 Medium relevance — show source text
For SI units: 1 inch = 25.4 mm
FIGURE 1312.9
METHOD OF INSTALLING A TEE FITTING SEDIMENT TRAP
[NFPA 54: FIGURE 9.6.8]
1312.10 Installation of Piping. Piping shall be installed in a manner not to interfere with inspection, maintenance, or servicing of the appliances. [NFPA 54:9.6.9] 1312.11 Liquefied Petroleum Gas (LP-Gas) Facilities and Piping. Liquefied petroleum gas (LP-Gas) facilities shall comply with NFPA 58.
1313.0 Pressure Testing, Inspection, and Purging. 1313.1 Piping Installations. Prior to acceptance and initial operation, all piping installations shall be visually inspected and pressure tested to determine that the materials, design, fabrication, and installation practices comply with the requirements of this code. [NFPA 54:8.1.1.1] 1313.1.1 Inspection Requirements. Inspection shall consist of visual examination, during or after manufacture, fabrication, assembly, or pressure tests. [NFPA 54:8.1.1.2] 1313.1.2 Repairs and Additions. Where repairs or additions are made following the pressure test, the affected piping shall be tested. Minor repairs and additions are not required to be pressure tested, provided that the work is inspected and connections are tested with a noncorrosive leak-detecting fluid or other leak-detecting methods approved by the Authority Having Jurisdiction.
[NFPA 54:8.1.1.3]
1313.1.3 New Branches. Where new branches are installed to new appliance(s), only the newly installed branch(es) shall be required to be pressure tested. Connections between the new piping and the existing piping shall be tested with a noncorrosive leak-detecting fluid or approved leak-detecting methods. [NFPA 54:8.1.1.4] 1313.1.4 Piping System. A piping system shall be tested as a complete unit or in sections. Under no circumstances shall a valve in a line be used as a bulkhead between gas in one section of the piping system and test medium in an adjacent section, unless a double block and bleed valve sys
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FUEL GAS PIPING
tem is installed. A valve shall not be subjected to the test pressure unless it can be determined that the valve, including the valve-closing mechanism, is designed to safely withstand the pressure. [NFPA 54:8.1.1.5]
1313.1.5 Regulators and Valves. Regulator and valve assemblies fabricated independently of the piping system in which they are to be installed shall be permitted to be tested with inert gas or air at the time of fabrication. [NFPA 54:8.1.1.6]
1313.1.6 Test Medium. The test medium shall be air, nitrogen, carbon dioxide, or an inert gas. Oxygen shall not be used as a test medium. [NFPA 54:8.1.2]
CMC § 2307.5 Medium relevance — show source text
Exception: The point of transfer for LP-gas dispensing operations 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.
LP-gas containers shall be located in accordance with Chapter 61. LP-gas storage and dispensing equipment shall be located outdoors.
2307.5 Additional requirements for LP-gas dispensers and equipment. LP-gas dispensers and related equipment shall comply with the following provisions:
Pumps shall be fixed in place and shall be designed to allow control of the flow and to prevent leakage and accidental discharge.
Dispensing devices installed within 10 feet (3048 mm) of where vehicle traffic occurs shall be protected against physical damage by mounting on a concrete island 6 inches (152 mm) or more in height, or shall be protected in accordance with Section 312.
Dispensing devices shall be securely fastened to their mounting surface in accordance with the dispenser manufacturer’s instructions.
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MOTOR FUEL-DISPENSING FACILITIES AND REPAIR GARAGES
2307.6 Installation of LP-gas dispensing devices and equipment. The installation and operation of LP-gas dispensing systems shall be in accordance with Sections 2307.6.1 through 2307.6.4 and Chapter 61. LP-gas dispensers and dispensing stations shall be installed in accordance with the manufacturer’s specifications and their listing.
2307.6.1 Product control valves. The dispenser system piping shall be protected from uncontrolled discharge in accordance with the following:
- Where mounted on a concrete base, a means shall be provided and installed within [1] / 2 inch (12.7 mm) of the top of the concrete base that will prevent flow from the supply piping in the event that the dispenser is displaced from its mounting.
- A manual shutoff valve and an excess flow-control check valve shall be located in the liquid line between the pump and the dispenser inlet where the dispensing device is installed at a remote location and is not part of a complete storage and dispensing unit mounted on a common base.
- An excess flow-control check valve or an emergency shutoff valve shall be installed in or on the dispenser at the point at which the dispenser hose is connected to the liquid piping.
- A listed automatic-closing type hose nozzle valve with or without a latch-open device shall be provided on island-type dispensers.
2307.6.2 Hoses. Hoses and piping for the dispensing of LP-gas shall be provided with hydrostatic relief valves. The hose length shall not exceed 18 feet (5486 mm). An approved method shall be provided to protect the hose against mechanical damage.
2307.6.3 Emergency breakaway devices. Dispenser hoses shall be equipped with a listed emergency breakaway device designed to retain liquid on both sides of the breakaway point. Where hoses are attached to hose-retrieving mechanisms, the emergency breakaway device shall be located such that the breakaway device activates to protect the dispenser from being displaced.
2307.6.4 Vehicle impact protection. Where installed within 10 feet of vehicle traffic, LP-gas storage containers, pumps and dispensers shall be protected in accordance with Section 2307.5, Item 2.
CMC § 303.5 Medium relevance — show source text
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GENERAL REGULATIONS
accordance with the manufacturer’s installation instructions.
Supports for appliances shall be designed and constructed to sustain vertical and horizontal loads within the stress limita tions specified in the building code.
303.5 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]
303.6 Identification of Equipment. Where more than one heating, cooling, ventilating, or refrigerating system is installed on the roof of a building or within a building, it shall be permanently identified as to the area or space served by the equipment.
303.7 Liquefied Petroleum Gas (LP-Gas) Facilities. Containers, container valves regulating equipment, and appurtenances for the storage and supply of liquefied petroleum gas (LP-Gas) shall be installed in accordance with NFPA 58 and the California Fire Code .
303.7.1 Liquefied Petroleum Gas (LP-Gas) Appli- ances. [HCD 1 & HCD 2] Liquefied petroleum gas- burning appliances shall not be installed in a pit, basement, or similar location where heavier-than-air gas might collect. Appliances so fueled shall not be installed in an above-grade under-floor space or basement unless such location is provided with an approved means for removal of unburned gas.
303.8 Appliances on Roofs. Appliances on roofs shall be designed or enclosed so as to withstand climatic conditions in the area in which they are installed. Where enclosures are provided, each enclosure shall permit easy entry and movement, shall be of reasonable height, and shall have at least a 30 inch (762 mm) clearance between the entire service access panel(s) of the appliance and the wall of the enclosure. [NFPA 54:9.4.1.1]
303.8.1 Load Capacity. Roofs on which appliances are to be installed shall be capable of supporting the additional load or shall be reinforced to support the additional load. [NFPA 54:9.4.1.2]
303.8.2 Fasteners. All access locks, screws, and bolts shall be of corrosion-resistant material. [NFPA 54:9.4.1.3]
303.8.3 Installation of Appliances on Roofs. Appliances shall be installed in accordance with the manufacturer’s installation instructions. [NFPA 54:9.4.2.1]
303.8.4 Edge of Roof Clearance. Appliances shall be installed on a well-drained surface of the roof. At least 6 feet (1829 mm) of clearance shall be available between any part of the appliance and the edge of a roof or similar hazard, or rigidly fixed rails, guards, parapets, or other building structures at least 42 inches (1067 mm) in height shall be provided on the exposed side. [NFPA 54:9.4.2.2]
303.8.4.1 Guards and Rails. Guards or rails shall be required where the following exist:
CMC § 1.11.0. Medium relevance — show source text
This state agency does not adopt sections identified with the following symbol: † The Office of the State Fire Marshal’s adoption of this chapter or individual sections is applicable to structures regulated by other state agencies pursuant to Section 1.11.0.
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CHAPTER 13
FUEL GAS PIPING
1301.0 Scope of Gas Piping.
1301.1 Applicability. The regulations of this chapter shall govern the installation of fuel gas piping in or in connection with a building, structure or within the property lines of premises up to 5 pounds-force per square inch (psi) (34 kPa) for natural gas and 10 psi (69 kPa) for undiluted propane, other than service pipe.
1302.0 Coverage of Piping System.
1302.1 General. Coverage of piping systems shall extend from the point of delivery to the appliance connections. For other than undiluted liquefied petroleum gas (LP-Gas) systems, the point of delivery shall be the outlet of the service meter assembly or the outlet of the service regulator or service shutoff valve where no meter is provided. For undiluted LP-Gas systems, the point of delivery shall be considered to be the outlet of the final pressure regulator, exclusive of line gas regulators where no meter is installed. Where a meter is installed, the point of delivery shall be the outlet of the meter.
[NFPA 54:1.1.1.1(A)]
1302.2 Piping System Requirements. Requirements for piping systems shall include design, materials, components, fabrication, assembly, installation, testing, inspection, operation, and maintenance. [NFPA 54:1.1.1.1(E)]
1302.3 Applications. This chapter shall not apply to the following items:
(1) Portable LP-Gas appliances and equipment of all types that are not connected to a fixed fuel piping system.
(2) Installation of appliances such as brooders, dehydrators, dryers, and irrigation equipment used for agricultural
purposes.
(3) Raw material (feedstock) applications except for piping to special atmosphere generators.
(4) Oxygen-fuel gas cutting and welding systems.
(5) Industrial gas applications using such gases as acetylene and acetylenic compounds, hydrogen, ammonia, carbon monoxide, oxygen, and nitrogen.
(6) Petroleum refineries, pipeline compressor or pumping stations, loading terminals, compounding plants, refinery tank farms, and natural gas processing plants.
(7) Large integrated chemical plants or portions of such plants where flammable or combustible liquids or gases are produced by chemical reactions or used in chemical reactions.
(8) LP-Gas installations at utility gas plants.
(9) Liquefied natural gas (LNG) installations.
(10)Fuel gas piping in electric utility power plants.
(11)Proprietary items of equipment, apparatus, or instruments such as gas-generating sets, compressors, and calorime ters.
(12)LP-Gas equipment for vaporization, gas mixing, and gas manufacturing.
CMC § 2307.2.1 Medium relevance — show source text
2307.2.1 Approved equipment. Containers, pressure relief devices (including pressure relief valves), pressure regulators and piping for LP-gas shall be approved.
2307.2.2 Listed equipment. Hoses, hose connections, vehicle fuel connections, dispensers, LP-gas pumps and electrical equipment used for LP-gas shall be listed.
2307.3 Attendants. Motor fuel-dispensing operations for LP-gas shall be conducted by qualified attendants or in accordance with Section 2307.7 by persons trained in the proper handling of LP-gas.
2307.4 Location of dispensing operations and equipment. The point of transfer for LP-gas dispensing operations shall be separated from buildings and other exposures in accordance with the following:
- Not less than 25 feet (7620 mm) from buildings where the exterior wall is not part of a fire-resistance-rated assembly having a rating of 1 hour or greater.
- Not less than 25 feet (7620 mm) from combustible overhangs on buildings, measured from a vertical line dropped from the face of the overhang at a point nearest the point of transfer.
- Not less than 25 feet (7620 mm) from the lot line of property that can be built on.
- Not less than 25 feet (7620 mm) from the centerline of the nearest mainline railroad track.
- Not less than 10 feet (3048 mm) from public streets, highways, thoroughfares, sidewalks and driveways.
- Not less than 10 feet (3048 mm) from buildings where the exterior wall is part of a fire-resistance-rated assembly having a rating of 1 hour or greater.
Exception: The point of transfer for LP-gas dispensing operations 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.
LP-gas containers shall be located in accordance with Chapter 61. LP-gas storage and dispensing equipment shall be located outdoors.
2307.5 Additional requirements for LP-gas dispensers and equipment. LP-gas dispensers and related equipment shall comply with the following provisions:
Pumps shall be fixed in place and shall be designed to allow control of the flow and to prevent leakage and accidental discharge.
Dispensing devices installed within 10 feet (3048 mm) of where vehicle traffic occurs shall be protected against physical damage by mounting on a concrete island 6 inches (152 mm) or more in height, or shall be protected in accordance with Section 312.
Dispensing devices shall be securely fastened to their mounting surface in accordance with the dispenser manufacturer’s instructions.
23-10 2025 CALIFORNIA FIRE CODE
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
MOTOR FUEL-DISPENSING FACILITIES AND REPAIR GARAGES
2307.6 Installation of LP-gas dispensing devices and equipment. The installation and operation of LP-gas dispensing systems shall be in accordance with Sections 2307.6.1 through 2307.6.4 and Chapter 61. LP-gas dispensers and dispensing stations shall be installed in accordance with the manufacturer’s specifications and their listing.
2307.6.1 Product control valves. The dispenser system piping shall be protected from uncontrolled discharge in accordance with the following: 1.
CMC § 303.2 Medium relevance — show source text
303.2 Closet or Alcove Installations. [Not adopted for OSHPD 1, 1R, 2, 3, 4 & 5] Central heating furnaces and boilers installed in closets or alcoves shall be listed for such
installation. Central heating furnaces not listed for closet or alcove installation shall be installed in a room or space having a volume not less than 12 times the total volume of the furnace. Central heating boilers not listed for closet or alcove installation shall be installed in a room or space having a volume 16 times the volume of the boiler. Where the ceiling height of the room or space exceeds 8 feet (2438 mm), the volume shall be calculated on the basis of an 8 foot (2438 mm) height.
The installation clearances shall be in accordance with
the appliance listing, shall not be reduced, and shall be installed in accordance with Section 904.3.
303.3 Unlisted Appliances. Except as otherwise permitted in this code, unlisted equipment and appliances shall be approved by the Authority Having Jurisdiction prior to being installed. Unlisted equipment and appliances shall be installed in accordance with the manufacturer’s installation instruc tions and with clearances from combustible materials in
accordance with Section 303.10 or Section 303.10.1.
303.4 Anchorage of Appliances. Appliances designed to be fixed in position shall be securely fastened in place in
52 2025 CALIFORNIA MECHANICAL CODE
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GENERAL REGULATIONS
accordance with the manufacturer’s installation instructions.
Supports for appliances shall be designed and constructed to sustain vertical and horizontal loads within the stress limita tions specified in the building code.
303.5 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]
303.6 Identification of Equipment. Where more than one heating, cooling, ventilating, or refrigerating system is installed on the roof of a building or within a building, it shall be permanently identified as to the area or space served by the equipment.
303.7 Liquefied Petroleum Gas (LP-Gas) Facilities. Containers, container valves regulating equipment, and appurtenances for the storage and supply of liquefied petroleum gas (LP-Gas) shall be installed in accordance with NFPA 58 and the California Fire Code .
303.7.1 Liquefied Petroleum Gas (LP-Gas) Appli- ances. [HCD 1 & HCD 2] Liquefied petroleum gas- burning appliances shall not be installed in a pit, basement, or similar location where heavier-than-air gas might collect. Appliances so fueled shall not be installed in an above-grade under-floor space or basement unless such location is provided with an approved means for removal of unburned gas.
CMC § 5.1 Medium relevance — show source text
N107.5.1 LP-gas containers exceeding 12 pounds (5 kg) of water capacity. The use of LP-gas containers exceeding 12 pounds (5 kg) of water capacity shall be prohibited.
N107.5.2 Where more than one LP-gas container is present in the same area. Where more than one LP-gas container is present in the same area, cylinders shall be separated from each other by a minimum of 20 feet (6096 mm).
N107.5.3 Equipment for LP-gas containers. Equipment for LP-gas containers, including tanks, piping, hoses, fittings, valves, tubing and other related components, shall be approved and shall comply with Chapter 61 and with the applicable requirements of the International Fuel Gas Code .
N107.5.4 Securing of LP-gas containers. Portable LP-gas containers shall be securely fastened in place to prevent unauthorized
movement.
N107.5.5 Spare LP-gas containers. Spare LP-gas containers not connected to an approved appliance shall be stored in a location and manner approved by the fire code official.
N107.6 Cooking and open-flame devices. All cooking equipment and any open-flame devices shall comply with the requirements of Section 308 of this code and with Chapter 5 of the California Mechanical Code . Cooking equipment shall be separated from combustible material display or storage by a horizontal distance of not less than 5 feet (1524 mm).
SECTION N108—MEANS OF EGRESS
N108.1 Means of egress from the indoor trade show or exhibition area. Means of egress from the indoor trade show or exhibition area shall comply with Chapter 10 and with Sections N108.2 and N108.3.
N108.2 Design of means of egress. The design of means of egress shall take into consideration the exhibit layout and the anticipated crowd movement during the event.
N108.3 Aisles and corridors. Aisles and corridors within the exhibit area shall be kept free of obstructions when the public is present. Storage of any kind in aisles or corridors within the exhibit area is not permitted.
SECTION N109—REFERENCED STANDARDS
N109.1 General. See Table N109.1 for standards that are referenced in various sections of this appendix. Standards are listed by the standard identification with the effective date, standard title, and the section or sections of this appendix that reference the standard.
TABLE N109.1—REFERENCED STANDARDS Col2 Col3 STANDARD ACRONYM STANDARD NAME SECTIONS HEREIN REFERENCED CBC—25 California Building Code N105.2 IFGC—24 International Fuel Gas Code N107.5.3 CMC—25 California Mechanical Code N107.6 2025 CALIFORNIA FIRE CODE APPENDIX N-5
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
APPENDIX N-6 2025 CALIFORNIA FIRE CODE
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
CALIFORNIA FIRE CODE – MATRIX ADOPTION TABLE
APPENDIX O – VALET TRASH AND RECYCLING COLLECTION IN GROUP R-2 OCCUPANCIES
CMC § 1310.4 Medium relevance — show source text
1310.4 Concealed Piping in Buildings . . . 285
1310.5 Piping in Vertical Chases . . . . . . . 286
1310.6 Maximum Operating Pressure in Buildings . . . . . . . . . . . . . . . . . . 286
1310.7 Appliance Overpressure Protection . . . . . . . . . . . . . . . . . . . 286
1310.8 Gas Pipe Turns. . . . . . . . . . . . . . . 286
1310.9 Drips and Sediment Traps . . . . . . 287
1310.10 Outlets . . . . . . . . . . . . . . . . . . . . . 287
1310.11 Manual Gas Shutoff Valves . . . . . 287
1310.12 Prohibited Devices . . . . . . . . . . . . 288
1310.13 Systems Containing Gas-Air Mixtures Outside the Flammable
Range . . . . . . . . . . . . . . . . . . . . . . 288
1310.14 Systems Containing Flammable Gas-Air Mixtures. . . . . . . . . . . . . . 288
1311.0 Electrical Bonding and Grounding. . . . . . . . . . . . . . . . . . . 289
1311.1 Pipe and Tubing other than CSST . . . . . . . . . . . . . . . . . . . . . . 289
1311.2 Bonding of CSST Gas Piping . . . . 289
1311.3 Arc-Resistant Jacketed CSST . . . 289
1311.4 Prohibited Use . . . . . . . . . . . . . . . 289
1311.5 Lightning Protection System. . . . . 289
1311.6 Electrical Circuits . . . . . . . . . . . . . 289
1311.7 Electrical Connections . . . . . . . . . 289
1312.0 Appliance and Equipment Connections to Building Piping. . . 289
1312.1 Connecting Appliances and Equipment . . . . . . . . . . . . . . . . . . 289
2025 CALIFORNIA MECHANICAL CODE
1312.2 Suspended Low-Intensity Infrared Tube Heaters . . . . . . . . . 290
1312.3 Use of Nonmetallic Gas Hose
Connectors . . . . . . . . . . . . . . . . . . 290
1312.4 Injection (Bunsen) Burners . . . . . . 290
1312.5 Connection of Portable and
Mobile Industrial Appliances. . . . . 290
1312.6 Appliance Shutoff Valves and Connections. . . . . . . . . . . . . . 291
1312.7 Quick-Disconnect Devices . . . . . . 291
1312.8 Gas Convenience Outlets. . . . . . . 291
1312.9 Sediment Trap . . . . . . . . . . . . . . . 291
1312.10 Installation of Piping . . . . . . . . . . . 291
1312.11 Liquefied Petroleum Gas Facilities and Piping . . . . . . . . . . . 291
CMC § 2306.8.1 Medium relevance — show source text
2306.8.1 Listed equipment. Dispensers shall be listed in accordance with UL 87A. Hoses, nozzles, breakaway fittings, swivels, flexible connectors or dispenser emergency shutoff valves, vapor recovery systems, leak detection devices and pumps used in alcohol-blended fuel-dispensing systems shall be listed for the specific purpose.
2306.8.2 Compatibility. Dispensers shall be used only with the fuels for which they have been listed and that are marked on the product. Field-installed components including hose assemblies, breakaway fittings, swivel connectors and hose nozzle valves shall be provided in accordance with the listing and the marking on the unit.
2306.8.3 Change of system contents. Fuel-dispensing systems subject to change in contents from gasoline to alcohol-blended fuels shall be subject to fire code official review and approval prior to commencing dispensing operations.
2306.8.4 Facility identification. Facilities dispensing alcohol-blended fuels shall be identified by an approved means.
2306.8.5 Marking. Dispensers shall be marked in an approved manner to identify the types of alcohol-blended fuels to be dispensed.
2306.8.6 Maintenance and inspection. Equipment shall be maintained and inspected in accordance with Section 2305.2.
SECTION 2307—LIQUEFIED PETROLEUM GAS MOTOR FUEL-DISPENSING FACILITIES
2307.1 General. Motor fuel-dispensing facilities for liquefied petroleum gas (LP-gas) fuel shall be in accordance with this section and Chapter 61.
2307.2 Approvals. Storage vessels and equipment used for the storage or dispensing of LP-gas shall be approved or listed in accordance with Sections 2307.2.1 and 2307.2.2.
2307.2.1 Approved equipment. Containers, pressure relief devices (including pressure relief valves), pressure regulators and piping for LP-gas shall be approved.
2307.2.2 Listed equipment. Hoses, hose connections, vehicle fuel connections, dispensers, LP-gas pumps and electrical equipment used for LP-gas shall be listed.
2307.3 Attendants. Motor fuel-dispensing operations for LP-gas shall be conducted by qualified attendants or in accordance with Section 2307.7 by persons trained in the proper handling of LP-gas.
2307.4 Location of dispensing operations and equipment. The point of transfer for LP-gas dispensing operations shall be separated from buildings and other exposures in accordance with the following:
- Not less than 25 feet (7620 mm) from buildings where the exterior wall is not part of a fire-resistance-rated assembly having a rating of 1 hour or greater.
- Not less than 25 feet (7620 mm) from combustible overhangs on buildings, measured from a vertical line dropped from the face of the overhang at a point nearest the point of transfer.
- Not less than 25 feet (7620 mm) from the lot line of property that can be built on.
- Not less than 25 feet (7620 mm) from the centerline of the nearest mainline railroad track.
- Not less than 10 feet (3048 mm) from public streets, highways, thoroughfares, sidewalks and driveways.
- Not less than 10 feet (3048 mm) from buildings where the exterior wall is part of a fire-resistance-rated assembly having a rating of 1 hour or greater.
CMC § 214.0 Medium relevance — show source text
LINE CONTACT INSTALLATION
Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 214.0
LIQUEFIED PETROLEUM GAS (LP-GAS)
Appliances . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 303.7.1
Automatic control devices . . . . . . . . . . . . . . . . . . . 306.0
Definition. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 209.0
2025 CALIFORNIA MECHANICAL CODE 583
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INDEX
Gas Facilities . . . . . . . . . . . . . . . . 214.0, 303.7, 1312.11
Shutoff devices. . . . . . . . . . . . . . . . . . . . . . . . . . D 110.4
Supply connections . . . . . . . . . . . . . . . D 101.2, D 106.1
LIQUID-FUELED ENGINES AND GAS TURBINES . . . . 1602.2
LISTED
Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 214.0
LISTED AND LISTING
Definition. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 214.0
LISTING AGENCY
Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 214.0
LOCATION OF
Appliances in garages . . . . . . . . 305.1.1, 305.1.2, 905.8
Appliances subject to
mechanical damage . . . . . . . . . . . . . . . . . . . . 305.1.1
Boilers, central heating . . . . . . . . . . . . . . . . . . . . . 904.2
Draft hoods and controls . . . . . . . . . . . . . 802.12, 905.5
Evaporative cooling systems. . . . . . . . . . . . . . . . . 932.2
Pool heaters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 926.2
Refrigerating equipment . . . . . . . . . . . . . . . . . . . 1106.1
Wall furnaces. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 907.3
LOUVERS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 315.0
LOUVERS, GRILLES,
Frequently asked questions
Can I use a flexible connector as the only support for a gas appliance?
No. The CMC requires appliances be supported and connected so they do not exert undue strain on the connections — flexible connectors are not intended to be load supports. Provide independent support (bracket, platform, or anchor). § 303.9
May I place a propane generator in a below‑grade utility room?
Not unless the room has an approved means for removal of unburned gas and the installation is approved by the AHJ. The code prohibits installation in pits/basements where heavier‑than‑air gas might collect absent an approved removal method (§ 303.7.1).
Where do I look for the technical rules for LP‑gas tanks, dispensers, and piping?
The CMC directs you to NFPA 58 and the California Fire Code for LP‑gas technical requirements; § 303.7 is the CMC section that makes that cross‑reference.
If the manufacturer’s installation instructions conflict with local interpretation, which controls?
Follow the CMC requirements and confer with the AHJ; appliances must be installed per manufacturer instructions and applicable codes. For LP‑gas specifics, NFPA 58 and the California Fire Code are the controlling standards referenced by § 303.7.
What counts as an “approved means for removal of unburned gas” in a basement?
The code text requires an approved means but does not prescribe a single method in § 303.7.1; this is an AHJ determination and commonly involves ventilation/forced‑exhaust systems designed and accepted by the fire code official and designed per NFPA/Fire Code guidance. Consult the AHJ and NFPA 58/CFC for designs.
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