CMC · California Mechanical Code
What systems and applications are excluded from Chapter 13
Chapter 13 does not apply to the specific list of portable, industrial, utility, refinery, LNG, and proprietary gas applications listed in § 1302.3 — if your system matches one of those numbered items, use the appropriate industry standard or other code instead.
Last reviewed: July 6, 2026
What the code requires — plain English
Chapter 13 of the California Mechanical Code is limited in scope: it governs fuel‑gas piping systems but does not apply to a specific list of industrial, portable, and specialty gas applications. The controlling provision for those exclusions is § 1302.3 — see the enumerated list of items that are expressly excluded.
Chapter 13 does not cover items on its exclusion list — if an application is on § 1302.3’s list, Chapter 13’s fuel‑gas rules do not apply.
Requirements in detail
Short rule
- If an application is one of the types listed in § 1302.3, it is excluded from Chapter 13. Consult the specific numbered item in § 1302.3 to confirm.
What is excluded (decision table)
Use this table when deciding whether Chapter 13 applies. For each application determine whether the item matches the description in the left column — if it does, Chapter 13 is not the correct chapter to use.
| Excluded application (decision trigger) | Typical indicator / how to spot it | Code reference |
|---|---|---|
| Portable LP‑Gas appliances | Appliances not connected to fixed piping (examples: portable grills, temporary cylinder‑fed heaters) | § 1302.3(1) |
| Agricultural appliances | Brooders, dehydrators, dryers, irrigation equipment used in agricultural operations | § 1302.3(2) |
| Raw‑material (feedstock) applications | Gas used as a chemical feedstock (not heating/fuel) — except piping to special atmosphere generators | § 1302.3(3) |
| Oxygen‑fuel cutting & welding systems | On‑site cutting/welding gas lines and equipment | § 1302.3(4) |
| Industrial gas applications | Use of acetylene, hydrogen, ammonia, CO, oxygen, nitrogen in industrial processes | § 1302.3(5) |
| Refineries, pipeline compressor/pumping stations, loading terminals, tank farms, gas processing plants | Large petroleum / gas industry facilities | § 1302.3(6) |
| Large integrated chemical plants (or portions thereof) | Facilities where gases/liquids are produced or used in chemical reactions | § 1302.3(7) |
| LP‑Gas at utility gas plants | Utility‑scale LP‑Gas production/handling sites | § 1302.3(8) |
| Liquefied natural gas (LNG) installations | On‑site LNG processing, storage, or transfer systems | § 1302.3(9) |
| Fuel‑gas piping in electric utility power plants | Power plant fuel gas supply piping | § 1302.3(10) |
| Proprietary items (gas‑generating sets, compressors, calorimeters, etc.) | Items that are manufacturer‑specific/unique equipment not ordinary building piping | § 1302.3(11) |
| LP‑Gas equipment for vaporization, gas mixing, gas manufacturing | Systems that vaporize, blend, or manufacture LP‑Gas on site | § 1302.3(12) |
(Each exclusion above is taken verbatim from the enumerated items in § 1302.3; use the matching subsection when you document the decision.)
How to use the list
- Match your project to the plain English triggers in the left column of the table. If you find a match, do not enforce Chapter 13 requirements (look to the standard(s) or code chapter that governs that specific application).
- If your application is not an obvious match, treat the list conservatively: if the gas is used as a feedstock or part of a manufacturing process or the installation is utility/refinery/plant scale, assume it’s excluded and confirm the applicable standard. § 1302.3 is the controlling exclusion list.
Exceptions & special cases
- Narrow or temporary installations that look like excluded items might still be covered by Chapter 13 if they are part of a fixed building piping system (contrast portable appliances in § 1302.3(1)). Confirm whether the appliance is connected to the building’s fixed piping.
- The exclusions are application‑based (what the gas is used for), not solely quantity‑based. Even small‑scale industrial feedstock use is excluded by § 1302.3(3).
- Many excluded items are regulated by other codes or standards (industry NFPA standards, fuel/gas industry regulations, or utility standards). If an item is excluded under § 1302.3, the appropriate standard will typically be referenced by the authority having jurisdiction — check that authority for the controlling standard.
Common mistakes
- Misreading “portable” vs “fixed”: assuming all cylinder‑fed devices are covered. If the device is not connected to fixed piping it’s excluded under § 1302.3(1).
- Treating industrial gas uses (acetylene, hydrogen, nitrogen, etc.) as ordinary building fuel: those are excluded under § 1302.3(5) and often fall under separate industrial safety standards.
- Assuming Chapter 13 covers LNG, utility plants, refineries, or large chemical plants — it does not; those are specifically excluded by § 1302.3(6), (7), (8), (9).
- Failing to check for overlapping jurisdiction: some proprietary equipment or process piping might be regulated by a different chapter or by an NFPA/industry standard rather than Chapter 13. Look for the applicable standard instead of defaulting to Chapter 13.
Worked example — practical scenario with numbers
Scenario: A small veterinary clinic installs a portable oxygen concentrator for emergency use. The concentrator is connected only to portable cylinders (not to building fixed piping). Is Chapter 13 applicable?
Step 1 — Identify trigger: this is a portable compressed gas appliance not connected to fixed piping. That matches § 1302.3(1).
Step 2 — Apply the rule: Because the unit is portable and not part of fixed fuel‑gas piping, Chapter 13 does not apply. The authority having jurisdiction or medical equipment standards (not Chapter 13) will govern storage and use requirements for the cylinders. Result: Chapter 13 is excluded by § 1302.3(1).
(If instead the clinic installed a fixed oxygen piped‑in system from a central source feeding wall outlets, that system would not be “portable” and Chapter 13 might apply only where the gas is fuel gas; medical gas piping is regulated in other parts of code — always confirm the proper chapter/standard for medical gases.)
Related provisions (CMC)
- § 1301.1 — Scope / applicability for fuel gas piping (limits and pressures referenced in Chapter 13).
- § 1302.1 — Coverage of piping systems (from point of delivery to appliance connections).
- § 1302.2 — Piping system requirements (design, materials, testing etc. — what Chapter 13 covers when it does apply).
(Use the specific § 1302.3 item to document why Chapter 13 does or does not apply to your installation; the related sections above define the Chapter’s scope when it does apply.)
Code references
Grounded in the retrieved California Mechanical Code — click a citation to read the verbatim passage:
CMC § 140.4 High relevance — show source text
Exception 3 to Section 140.4(q): Where more than 60 percent of the outdoor air heating energy is provided from site-recovered energy in Climate Zone 16.
Exception 4 to Section 140.4(q): Where the sum of the airflow rates exhausted and relieved within 20 feet of each other is less than 75 percent of the design outdoor airflow rate, excluding exhaust air that is either:
- Used for another energy recovery system,
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NONRESIDENTIAL AND HOTEL/MOTEL OCCUPANCIES—PERFORMANCE AND PRESCRIPTIVE
COMPLIANCE APPROACHES FOR ACHIEVING ENERGY EFFICIENCY
- Not allowed by the California Mechanical Code (Title 24, Part 4) (CMC) for use in energy recovery systems with leakage potential, or
- Of Class 4 as specified in Section 120.1(g).
Exception 5 to Section 140.4(q): Systems expected to operate less than 20 hours per week.
Note: Authority: Sections 25213, 25218, 25218.5, 25402 and 25402.1, Public Resources Code. Reference: Sections 25007, 25008, 25218.5, 25310, 25402, 25402.1, 25402.4, 25402.8, and 25943, Public Resources Code.
TABLE 140.4-J—ENERGY RECOVERY REQUIREMENTS BY CLIMATE ZONE AND PERCENT
OUTDOOR AIR AT FULL DESIGN AIRFLOW (< 8,000 HOURS/YEAR)Col2 Col3 Col4 Col5 Col6 Col7 Col8 Col9 Col10 Col11 Col12 Col13 Col14 Col15 Col16 Col17 % OUTDOOR
AIR AT FULL
DESIGN
AIRFLOW**1 ** **2 ** **3 ** **4 ** **5 ** **6 ** **7 ** **8 ** **9 ** 10 11 12 13 14 15 16 ≥ 10% and < 20% NR NR NR NR NR NR NR NR NR NR NR NR NR NR NR NR ≥ 20% and < 30% ≥ 15,000 ≥ 20,000 NR NR NR NR NR NR NR NR ≥ 18,500 ≥ 18,500 ≥ 18,500 ≥ 18,500 ≥ 18,500 ≥ 18,500 ≥ 30% and < 40% ≥ 13,000 ≥ 15,000 NR NR NR NR NR NR NR NR ≥ 15,000 ≥ 15,000 ≥ 15,000 ≥ 15,000 ≥ 15,000 ≥ 15,000 ≥ 40% and < 50% ≥ 10, CMC § 160.3 High relevance — show source text
Mass radiant floor slab systems shall incorporate floor temperature onto the optimum start algorithm. Exception to Section 160.3(a)2J: Systems that must operate continuously.
(b) Dwelling unit space-conditioning and air distribution systems.
- Building cooling and heating loads. Building heating and cooling loads shall be determined using a method based on any one of the following, using cooling and heating loads as two of the criteria for equipment sizing and selection: A. The ASHRAE Handbook, Equipment Volume, Applications Volume and Fundamentals Volume; or B. The SMACNA Residential Comfort System Installation Standards Manual; or
C. The ACCA Manual J.
Exception to Section 160.3(b)1: Block loads, the total load for all rooms combined that are served by the central equipment, may be used for the purpose of system sizing for additions. NOTE: Heating systems are required to have a minimum heating capacity adequate to meet the minimum requirements of the CBC.
- Design conditions . Design conditions shall be determined in accordance with the following: A. For the purpose of sizing the space-conditioning (HVAC) system, the indoor design temperatures shall be 68°F for heating and 75°F for cooling. B. Outdoor design conditions shall be selected from one of the following: i. Reference Joint Appendix JA2, which is based on data from the ASHRAE Climatic Data for Region X; or ii. The ASHRAE Handbook Fundamentals Volume; or
iii. The ACCA Manual J.
C. The outdoor design temperatures for heating shall be no lower than the 99.0 percent Heating Dry Bulb or the Heating Winter Median of Extremes values.
D. The outdoor design temperatures for cooling shall be no greater than the 1.0 percent Cooling Dry Bulb and Mean Coincident Wet Bulb values.
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MULTIFAMILY BUILDINGS—MANDATORY REQUIREMENTS
- Outdoor condensing units . A. Clearances. Installed air conditioner and heat pump outdoor condensing units shall have a clearance of at least 5 feet (1.5 meters) from the outlet of any dryer vent. B. Liquid line drier. Installed air conditioner and heat pump systems shall be equipped with liquid line filter driers if required, as specified by manufacturer’s instructions.
- Central forced-air heating furnaces . A. Temperature rise . Central forced-air heating furnace installations shall be configured to operate in conformance with the furnace manufacturer's maximum inlet-to-outlet temperature rise specifications.
- Air-distribution and ventilation system ducts, plenums and fans. A. CMC compliance.
i. All air-distribution system ducts and plenums, including, but not limited to, mechanical closets and air-handler boxes, shall meet the requirements of the CMC Sections 601.0, 602.0, 603.0, 604.0 and 605.0 and ANSI/SMACNA006-2006 HVAC Duct Construction Standards Metal and Flexible 3rd Edition, incorporated herein by reference. ii. Portions of supply-air and return-air ducts and plenums of a space heating or cooling system shall be insulated in accordance with either Subsection a or b below:
a. Ducts shall have a minimum installed level of R-6.0, or
CMC § 1.1 High relevance — show source text
1.1_
1304.1.2||||||||||X|X|X|X|X|X||||||||||This state agency does not adopt sections identified with the following symbol: The Office of the State Fire Marshal’s adoption of this chapter or individual sections is applicable to structures regulated by other state agencies pursuant to Section 1.11.0.
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CHAPTER 13
HEALTH CARE FACILITIES AND MEDICAL GAS AND MEDICAL VACUUM SYSTEMS
Part I – General Requirements.
1301.0 General Requirements.
1301.1 Applicability. This chapter applies to the special fixtures and systems in health care facilities; the special plumbing requirements for such facilities; and the installation, testing, and verification of Categories 1, 2, and 3 medical gas and medical vacuum piping systems, except as otherwise indicated in this chapter, from the central supply system to the station outlets or inlets in hospitals, clinics, and other health care facilities. Other plumbing in such facilities shall comply with other applicable sections of this code. For Category 3 medical gas systems, only oxygen and nitrous oxide shall be used.
1301.2 Where Not Applicable. This chapter does not apply to the following except as otherwise addressed in this chapter:
(1) Cylinder and container management, storage, and reserve requirements
(2) Bulk supply systems
(3) Electrical connections and requirements
(4) Motor requirements and controls
(5) Systems having nonstandard operating pressures
(6) Waste anesthetic gas disposal (WAGD) systems
(7) Surface-mounted medical gas rail systems
(8) Breathing air replenishment (BAR) systems
(9) Portable compressed gas systems
(10)Medical support gas systems
(11)Gas-powered device supply systems
(12)Scavenging systems 1301.3 Conflict of Requirements. The requirements of this chapter shall not be interpreted to conflict with the requirements of NFPA 99. For requirements of portions of medical gas and vacuum systems not addressed in this chapter or medical gas and vacuum systems beyond the scope of this chapter refer to NFPA 99.
1301.4 Where Required. Construction and equipment requirements shall be applied only to new construction and new equipment, except as modified in individual sections of this chapter. {NFPA 99:1.3.2} 1301.5 Existing Systems. Only the altered, renovated, or modernized portion of an existing system or individual component shall be required to meet the installation and equipment requirements stated in this code. If the alteration, renovation, or modernization adversely impacts the existing performance requirements of a system or component, additional upgrading shall be required. An existing system that is not in strict compliance with the provisions of this code shall be permitted to be continued in use, unless the Authority Having Jurisdiction has determined that such use constitutes a distinct hazard to life. [NFPA 99:1.3.2.1 – 1.3.2.3]
1302.0 Design Requirements. **1302.1 Risk Categories.
CMC § 304.8 High relevance — show source text
Exception: Area of the building footprint is excluded from the calculation.
A5.304.8 Graywater irrigation system. Install a graywater collection system for onsite subsurface irrigation using graywater collected from bathtubs, showers, bathroom wash basins and laundry water. See California Plumbing Code.
SECTION A5.305—WATER REUSE
A5.305.1 Nonpotable water systems. Nonpotable water systems for indoor and outdoor use shall comply with the current edition of the California Plumbing Code.
A5.305.2 Irrigation systems. Irrigation systems regulated by a local water efficient landscape ordinance or by the California Department of Water Resources Model Water Efficient Landscape Ordinance (MWELO) shall use recycled water.
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APPENDIX A5-22 2025 CALIFORNIA GREEN BUILDING STANDARDS CODE
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CALIFORNIA GREEN BUILDING STANDARDS CODE – MATRIX ADOPTION TABLE
APPENDIX A5 – NONRESIDENTIAL VOLUNTARY MEASURES
DIVISION A5.4 – MATERIAL CONSERVATION AND RESOURCE EFFICIENCY
(Matrix Adoption Tables are nonregulatory, intended only as an aid to the code user. See Chapter 1 for state agency authority and building applications.)
Adopting agency BSC BSC-
CGSFM HCD Col6 Col7 DSA Col9 OSHPD Col11 Col12 Col13 Col14 Col15 BSCC DPH AGR DWR CEC CA SL SLC Adopting agency BSC BSC-
CGSFM 1 2 1/AC AC SS 1 1R 2 3 4 5 5 5 5 5 5 5 5 5 Adopt entire CA chapter X Adopt entire chapter as
amended (amended
sections listed below)Adopt only those sections
that are listed belowChapter/Section 2025 CALIFORNIA GREEN BUILDING STANDARDS CODE APPENDIX A5-23
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A5 NONRESIDENTIAL VOLUNTARY MEASURES
DIVISION A5.4 – MATERIAL CONSERVATION AND RESOURCE EFFICIENCY
SECTION A5.401—GENERAL
CMC § 4.6.1.1 High relevance — show source text
Where the state or other political subdivision does not assume jurisdiction, such fuel gas piping and equipment installations shall be designed and installed in accordance with the applicable provisions of NFPA 54 or NFPA 58. [NFPA 501A:4.6.1.1 – 4.6.1.2] D 115.2 Oil Supply Systems in Manufactured Home Communities. Oil-burning equipment and installation within a manufactured home community shall be designed and constructed in accordance with the applicable codes and standards adopted by the Authority Having Jurisdiction. Where the state or other political subdivision does not assume jurisdiction, such installations shall be designed and constructed in accordance with the applicable provisions of NFPA 31. [NFPA 501A:4.6.2.1 – 4.6.2.2] D 115.3 Oil-Burning Equipment and Installation. Oilburning equipment and installation within a building constructed in a manufactured home community in accordance with the local building code or a nationally recognized building code shall comply with nationally recognized codes and standards adopted by the Authority Having Jurisdiction. Where the state or other political subdivision does not assume jurisdiction, such oil-burning equipment and installations shall be designed and installed in accordance with the applicable provisions of NFPA 31. [NFPA 501A:4.6.3.1 – 4.6.3.2] D 115.4 Inspection and Tests. Inspections and tests for fuel gas piping shall be made in accordance with Chapter 1 and Chapter 13 of this code.
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CALIFORNIA MECHANICAL CODE – MATRIX ADOPTION TABLE
APPENDIX E – SUSTAINABLE PRACTICES
(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 § 120.4 High relevance — show source text
Nonresidential and hotel/motel buildings shall comply with the applicable requirements of Sections 120.4(a) through 120.4(g).
Exception to Section 120.4: Systems serving healthcare facilities shall comply with the applicable requirements of the California Mechanical Code.
(a) CMC compliance. All air distribution system ducts and plenums, including but not limited to building cavities, mechanical closets, air-handler boxes and support platforms used as ducts or plenums, shall meet the requirements of the CMC Sections 601.0, 602.0, 603.0, 604.0, and 605.0, and ANSI/SMACNA-006-2006 HVAC Duct Construction Standards Metal and Flexible, 3rd Edition incorporated herein by reference. Connections of metal ducts and the inner core of flexible ducts shall be mechanically fastened. Openings shall be sealed with mastic, tape, aerosol sealant or other duct-closure system that meets the applicable requirements of UL 181, UL 181A, or UL 181B. If mastic or tape is used to seal openings greater than [1] / 4 inch, the combination of mastic and either mesh or tape shall be used.
Portions of supply-air and return-air ducts conveying heated or cooled air located in one or more of the following spaces shall be insulated to a minimum installed level of R-8:
Outdoors; or
In a space between the roof and an insulated ceiling; or
In a space directly under a roof with fixed vents or openings to the outside or unconditioned spaces; or
In an unconditioned crawlspace; or
In other unconditioned spaces.
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NONRESIDENTIAL, HOTEL/MOTEL OCCUPANCIES, AND COVERED PROCESSES—MANDATORY REQUIREMENTS
Portions of supply-air ducts that are not in one of these spaces, including ducts buried in concrete slab, shall be insulated to a minimum installed level of R-4.2 or be enclosed in directly conditioned space.
(b) Duct and plenum materials.
- Factory-fabricated duct systems. A. All factory-fabricated duct systems shall comply with UL 181 for ducts and closure systems, including collars, connections and splices, and be labeled as complying with UL 181. UL 181 testing may be performed by UL laboratories or a laboratory approved by the Executive Director. B. All pressure-sensitive tapes, heat-activated tapes, and mastics used in the manufacture of rigid fiberglass ducts shall comply with UL 181 and UL 181A. C. All pressure-sensitive tapes and mastics used with flexible ducts shall comply with UL 181 and UL 181B. D. All ductwork and plenums with pressure class ratings shall be constructed to Seal Class A. Joints and seams of duct systems and their components shall not be sealed with cloth-back rubber adhesive duct tapes unless such tape is used in combination with mastic and drawbands.
Exception to Section 120.4(b)1D: Ductwork located in occupied space and exposed to view is not required to meet Seal Class A.
CMC § 1.11.0. Medium relevance — show source text
APPENDIX D – FUEL SUPPLY: MANUFACTURED/MOBILE HOME PARKS AND RECREATIONAL VEHICLE PARKS
(Matrix Adoption Tables are non-regulatory, intended only as an aid to the code user. See Chapter 1 for state agency authority and building applications.)
Adopting Agency BSC BSC-
CGSFM HCD Col6 Col7 DSA Col9 Col10 OSHPD Col12 Col13 Col14 Col15 Col16 Col17 BSCC DPH AGR DWR CEC CA SL SLC Adopting Agency BSC BSC-
CGSFM 1 2 1-AC AC ** SS** ** SS/CC** 1 1R 2 3 4 5 6 6 6 6 6 6 6 6 6 Adopt Entire Chapter Adopt Entire Chapter as
amended (amended sections
listed below)Adopt only those sections
that are listed belowChapter/Section This state agency does not adopt sections identified with the following symbol: † The Office of the State Fire Marshal’s adoption of this chapter or individual sections is applicable to structures regulated by other state agencies pursuant to Section 1.11.0.
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APPENDIX D
FUEL SUPPLY: MANUFACTURED/MOBILE HOME PARKS AND
RECREATIONAL VEHICLE PARKS
The provisions contained in this appendix are not mandatory unless specifically adopted by a state agency, or referenced in the adopting ordinance.
D 101.0 Fuel Gas Piping Systems. D 101.1 General. All fuel gas piping systems serving manufactured homes, accessory buildings, or structures and communities shall be designed and constructed in accordance with any applicable provisions of Chapter 13 or NFPA 54 and NFPA 58. NFPA 31 shall apply to oil fuel-burning systems and shall conform to the criteria of the Authority Having Jurisdiction. {NFPA 501A:4.1.1.1 – 4.1.1.2} D 101.2 Gas Supply Connections. Gas supply connections at sites, where provided from an underground gas supply piping system, shall be located and arranged to permit attachment to a manufactured home occupying the site. For the installation of liquefied petroleum gas (LP-Gas) storage systems, the provisions of NFPA 58 shall be followed.
CMC § 206.0 Medium relevance — show source text
Durham, definition . . . . . . . . . . . . . . . . . . . . . . . . .206.0 Engineered . . . . . . . . . . . . . .509.10.8.1, 912.0, C 201.1 Exhaust . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .507.21,
509.3.4, 509.6.1 Fire protection (protection from) . . . . . . . . . . . .603.5.14 Firefighter breathing air replenishment . . . . . . . . . . . . . . . . . . .Appendix F Firestop . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Chapter 14 Fire sprinklers . . . . . . . . . . . . . . . . . . . . . . . . . . . .612.1 FOG disposal . . . . . . . . . . . . . . . . . . . . . . . . . . . .1015.0 Fuel gas piping . . . . . . . . . . . . . . . .507.18, Chapter 12,
E 401.0 – E 406.4
Fuel gas venting . . . . . . . . . . .509.0, Table 509.4, 510.0 Gray water . . . . . . . . . . . . . . . . . . . . . . .601.3.3, 1502.0 Independent . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .311.0 Lightning protection . . . . . . . . . . . . . . . . . . . . . . .1211.5 Macerating toilet . . . . . . . . . . . . . . . . . . . . . . . . .710.13 Mechanical draft . . . . . . . . . . . . . . .509.3.3, 509.10.3.2,
509.10.7
Medical gas and medical vacuum . . . . . . . . . . .319.0, Chapter 13 Natural draft venting . . . . . . . . . . . . . . . . . . . .509.6.2.1 On-site treated nonpotable . . . . . . . . . . .601.3.3, 1506.0 Plumbing vent, definition . . . . . . . . . . . . . . . . . . . .218.0 Plumbing venting . . . . . . . . . .710.7, Chapter 9, C 401.0
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INDEX
Potable water
Contamination and damage . . . . . .C 302.1, C 302.2, C 501.3
Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .218.0
CMC § 5801.1 Medium relevance — show source text
User notes:
About this chapter: Chapter 58 sets requirements for the storage and use of flammable gases. For safety purposes, there is a limit on the quantities of flammable gas allowed per control area. Exceeding these limitations increases the possibility of damage to both property and individuals. The principal hazard posed by flammable gas is its ready ignitability, or even explosivity, when mixed with air in the proper proportions. Consequently, occupancies storing or handling large quantities of flammable gas are classified as Group H-2 (high hazard) by the California Building Code .
SECTION 5801—GENERAL
5801.1 Scope. The storage and use of flammable gases and flammable cryogenic fluids shall be in accordance with this chapter, NFPA 2 and NFPA 55. Compressed gases shall also comply with Chapter 53 and cryogenic fluids shall also comply with Chapter 55. Flammable cryogenic fluids shall comply with Section 5806. Hydrogen motor fuel-dispensing stations and repair garages and their associated above-ground hydrogen storage systems shall also be designed, constructed and maintained in accordance with Chapter 23. Mobile fueling of hydrogen-fueled vehicles shall comply with Section 5809.
Exceptions:
- Gases used as refrigerants in refrigeration systems (see Section 608).
- Liquefied petroleum gases and natural gases regulated by Chapter 61.
- Fuel-gas systems and appliances regulated under the California Mechanical Code and the California Plumbing Code other than gaseous hydrogen systems and appliances.
- Pyrophoric gases in accordance with Chapter 64.
5801.2 Permits. Permits shall be required as set forth in Section 105.5.
SECTION 5802—DEFINITIONS
5802.1 Definitions. The following terms are defined in Chapter 2:
FLAMMABLE GAS.
FLAMMABLE LIQUEFIED GAS.
GAS DETECTION SYSTEM.
GASEOUS HYDROGEN SYSTEM.
HYDROGEN FUEL GAS ROOM.
METAL HYDRIDE.
METAL HYDRIDE STORAGE SYSTEM.
SECTION 5803—GENERAL REQUIREMENTS
5803.1 Quantities not exceeding the maximum allowable quantity per control area. The storage and use of flammable gases in amounts not exceeding the maximum allowable quantity per control area indicated in Section 5003.1 shall be in accordance with Sections 5001, 5003, 5801 and 5803.
5803.1.1 Special limitations for indoor storage and use. Flammable gases shall not be stored or used in Group A, E, I or R occupancies or in offices in Group B occupancies.
Exceptions:
- Cylinders of nonliquefied compressed gases not exceeding a capacity of 250 cubic feet (7.08 m [3] ) or liquefied gases not exceeding a capacity of 40 pounds (18 kg) each at normal temperature and pressure (NTP) used for maintenance purposes, patient care or operation of equipment.
- Food service operations in accordance with Section 6103.2.1.7.
- Hydrogen gas systems located in a hydrogen fuel gas room constructed in accordance with Section 421 of the Califor- nia Building Code .
5803.1.1.1 Medical gases. Medical gas system supply cylinders shall be located in medical gas storage rooms or gas cabinets as set forth in Section 5306.
CMC § 6-3 Medium relevance — show source text
603 Electrical Equipment, Wiring and Hazards . . . . . . . . . 6-3 604 Elevator Operation, Maintenance and Fire Service Keys . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-5 605 Fuel-Fired Appliances. . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-6 606 Commercial Cooking Equipment and Systems . . . . . 6-9 607 Commercial Cooking Oil Storage. . . . . . . . . . . . . . . . . 6-10 608 Mechanical Refrigeration. . . . . . . . . . . . . . . . . . . . . . . . 6-10 609 Hyperbaric Facilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-13 610 Clothes Dryer Exhaust Systems . . . . . . . . . . . . . . . . . . 6-13
CHAPTER 7 FIRE AND SMOKE PROTECTION
FEATURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-3
701 General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-3
702 Definitions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-3
703 Penetrations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-4
704 Joints and Voids. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-4
705 Door and Window Openings . . . . . . . . . . . . . . . . . . . . . . 7-4 706 Duct and Air Transfer Openings . . . . . . . . . . . . . . . . . . . 7-5 707 Concealed Spaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-5 708 Spray Fire-Resistant Materials and Intumescent Fire-Resistant Materials . . . . . . . . . . . . . . . . . . . . . . . . 7-5
709 Exterior Walls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-5
CHAPTER 8 INTERIOR FINISH, DECORATIVE
MATERIALS AND FURNISHINGS . . . . . . . . . . . . . . . . . . . . .8-3
801 General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-3
CMC § 5.105.2 Medium relevance — show source text
Exception: Combined addition(s) to existing building(s) of two times the area or more of the existing building(s) is not eligible to meet compliance with Section 5.105.2 or Section A5.105.2.
A5.409.2 Whole building life cycle assessment. Projects shall meet the minimum requirements of Section A5.409.2 for Tier 1 or Tier 2 compliance.
A5.409.2.1 Tier 1. Projects shall conduct a cradle-to-grave whole building life cycle assessment meeting the requirements of Section 5.409.2 and performed in accordance with ISO 14040 and 14044, excluding operating energy, demonstrating a minimum 15-percent reduction in global warming potential (GWP) as compared to a reference baseline building of similar size, function, complexity, type of construction, material specification, and location that meets the requirements of all parts of the California Building Standards Code currently in effect. Software used to conduct the whole building life cycle assessment, including reference baseline building, shall have a data set compliant with ISO 14044, and ISO 21930 or EN 15804, and the software shall conform to ISO 21931 and/or EN 15978. The software tools and data sets shall be the same for evaluation of both the baseline building and the proposed building.
Exception: For projects that include building reuse, the reference baseline building shall exclude the reused elements. The percent reduction in GWP shall be achieved through the design and construction of new project elements.
A5.409.2.2 Tier 2. Projects shall conduct a cradle-to-grave whole building life cycle assessment meeting the requirements of Section 5.409.2 and performed in accordance with ISO 14040 and ISO 14044, excluding operating energy, demonstrating a minimum 20-percent reduction in GWP as compared to a reference baseline building of similar size, function, complexity, type of construction, material specification, and location that meets the requirements of all parts of the California Building Standards Code currently in effect. Software used to conduct the whole building life cycle assessment, including reference baseline building, shall have a data set compliant with ISO 14044, and ISO 21930 or EN 15804, and the software shall conform to ISO 21931 and/or EN 15978. The software tools and data sets shall be the same for evaluation of both the baseline building and the proposed building.
Exception: For projects that include building reuse, the reference baseline building shall not be of new construction and shall retain existing materials. The percent reduction in GWP shall be achieved through the design and construction of new project elements.
A5.409.2.3 Verification of compliance. A summary of the GWP analysis produced by the software and Worksheet WS-7 signed by the design professional of record shall be provided in the construction documents as documentation of compliance. A copy of the whole building life cycle assessment which includes the GWP analysis produced by the software, in addition to maintenance and training information, shall be included in the operation and maintenance manual and shall be provided to the owner at the close of construction. The enforcing agency may require inspection and inspection reports in accordance with Sections 702.2 and 703.1 during and at completion of construction to demonstrate substantial conformance. Inspection shall be performed by the design professional of record or third party acceptable to the enforcing agency.
A5.409.3 Product GWP compliance—prescriptive path. Each product that is permanently installed and listed in Table A5.409.3 shall have a Type III environmental product declaration (EPD), either product-specific or factory-specific.
CMC § 707.1 Medium relevance — show source text
Cleanouts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .707.1
Drainage piping, joints, and fittings . . . . . . . . . . . . . . . . . . .701.2, Table 701.2, 701.3, 705.0
Fuel gas piping, joints, and fittings . . . . . . . . . . . . . . . . . . . .1208.5, 1208.5.1,
1208.5.3 – 1208.5.4,
1208.5.9, 1208.5.10, 1208.5.11
Marking of . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .301.2.1 Medical gas and medical vacuum . . . . . . . . . . . .1318.0 Potable water piping, joints, and fittings . . . . . . . . . . . . . . . . . . . .604.0, 605.0 Rainwater catchment system . . . . . .1602.7, Appendix K Septic tanks . . . . . . . . . . . . . . . . . . . . . . . . . . . .H 501.3 Storm drainage pipe . . . . . . . . . . . . . . . . . . . . . . .1101.4
Subsoil drain . . . . . . . . . . . . . . . . . . . . . . . . . . .1101.4.6
Sumps or receiving tanks . . . . . . . . . . . . . . . . . . .710.8 Traps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1003.1 Vents (DWV) . . . . . . . . . . . . . . . . . . .Table 701.2, 903.0 MAY, DEFINITION . . . . . . . . . . . . . . . . . . . . . . . . . . . .215.0
MEAT AND POULTRY
PROCESSING PLANTS . . . . . . . . . . . .601.5, 724.0, 1010.2
MEAT PACKING AND SLAUGHTERHOUSES . . . . .1010.0
MEDICAL GAS AND MEDICAL
VACUUM SYSTEMS . . . . . . . . . . . . . . . . . . . .Chapter 13
Alarms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1324.4
CMC § 1.11.0. High 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.
2025 CALIFORNIA MECHANICAL CODE 273
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274 2025 CALIFORNIA MECHANICAL CODE
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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 § 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 § 8.13.6.2 High relevance — show source text
(1) Refrigerant compressors
(2) Refrigerant pumps
(3) Normally closed automatic refrigerant valves
(4) Other unclassified electrical sources of ignition with apparent power rating greater than 1 kVA, where the apparent power is the product of the circuit voltage and current rating. [ASHRAE 15:8.13.6.2] 1106.11.7 Mechanical Equipment Control. Remote control of the mechanical equipment in the refrigerating machinery room shall be provided immediately outside the machinery room door solely for the purpose of shutting down the equipment in an emergency. Ventilation fans shall be on a separate electrical circuit and have a control switch located immediately outside the machinery room door. [ASHRAE 15:8.13.7] 1106.11.8 Refrigerant Detectors. Each refrigerating machinery room in accordance with Section 1106.11 shall contain one or more refrigerant detectors in accordance with Section 1106.11.9. The detector(s) sensing element shall be located in areas where refrigerant from a leak will concentrate, with one or more set points that activate responses in accordance with Section 1106.11.10 for alarms and Section 1106.11.11 for mechanical ventilation. Multiport-type devices shall be prohibited. {ASHRAE 15:8.13.8} 1106.11.9 Refrigerant Detectors Requirements. Refrigerant detectors required by Section 1106.11 shall meet all of the following conditions:
(1) A refrigerant detector shall be capable of detecting each of the specific refrigerant designations in the machinery room.
(2) The refrigerant detector shall activate responses within a time not to exceed a limit specified in Section 1106.11.10 and Section 1106.11.11 after exposure to refrigerant concentration exceeding a limit value specified in Section 1106.11.10 and Section 1106.11.11.
(3) The refrigerant detector shall have a set point not greater than the applicable Occupational Exposure Limit (OEL) value in accordance with Table 1102.3. The applicable OEL value shall be the lowest OEL value for any refrigerant designation in the machinery room. For refrigerants that do not have an OEL value in Table 1102.3, use a value determined in accordance with the OEL as defined by ASHRAE 34 where approved by the Authority Having Jurisdiction.
(4) The refrigerant detector shall have a set point not more than the applicable Refrigerant Concentration Limit (RCL) value in accordance with Table 1102.3. The applicable RCL value shall be the lowest RCL value for any refrigerant designation in the machinery room. For refrigerants that do not have a RCL value in Table 1102.3, use a value determined in accordance with the RCL as defined by ASHRAE 34 where approved by the Authority Having Jurisdiction.
(5) The refrigerant detector shall provide a means for automatic self-testing and shall be in accordance with Section 1106.11.10.4. The refrigerant detector shall be tested during installation and annually thereafter in accordance with the fire code, or at an interval not exceeding the manufacturer’s installation instructions, whichever is less. Testing shall verify compliance with the alarm set points and response times per Section 1106.11.10 and Section 1106.11.11. [ASHRAE 15:8.13.9]
CMC § 0.228 High relevance — show source text
657|0.228|0.096|0.025| |19.77|2.750|0.699|0.243|0.102|0.026| |20.48|2.925|0.744|0.258|0.109|0.028| |21.19|3.106|0.790|0.274|0.115|0.030| |24.72|4.074|1.034|0.358|0.151|0.039| |28.25|–|1.307|0.452|0.190|0.049| |31.78|–|1.608|0.556|0.234|0.060| |35.31|–|1.936|0.669|0.281|0.072| |38.84|–|2.291|0.791|0.332|0.085| |42.37|–|2.672|0.922|0.387|0.099| |45.90|–|3.078|1.062|0.446|0.113| |49.43|–|3.510|1.211|0.508|0.129| |52.97|–|3.969|1.368|0.574|0.146| |56.50|–|4.450|1.534|0.643|0.163| |63.56|–|–|1.890|0.792|0.201| |70.62|–|–|2.278|0.954|0.242| |77.68|–|–|2.699|1.130|0.286| |84.74|–|–|3.151|1.318|0.334| |91.81|–|–|3.634|1.520|0.385| |98.87|–|–|4.148|1.734|0.439| |105.93|–|–|4.691|1.961|0.496| |112.99|–|–|–|2.200|0.556|
For SI units: 1 standard cubic foot per minute = 28.32 SLPM, 1 inch = 25 mm, 1 foot = 304.8 mm, 1 inch of mercury = 3.386 kPa Notes: 1 Based on the pressure of 14.7 psig (101 kPa) at 68°F (20°C). 2 Based on the pressure of 19 inches of mercury gauge vacuum (64 kPa) at 68°F (20°C).
1323.3 Location of Piping. Piping risers shall be permitted to be installed in pipe shafts if protected from physical damage, effects of excessive heat, corrosion, or contact with oil. [NFPA 99:5.1.10.11.3.1] 1323.3.1 Prohibited Locations. Piping shall not be installed in kitchens, stairwells, elevator shafts, elevator machine rooms, areas with open flames, electrical service equipment over 600 volts, and areas prohibited Cal- ifornia Electrical Code except for the following locations:
(1) Room locations for medical air compressor supply systems and medical-surgical vacuum pump supply systems
(2) Room locations for secondary distribution circuit panels and breakers having a maximum voltage rating of 600 volts [NFPA 99:5.1.10.11.3.2] **1323.3.2 Approved Locations.
CMC § 1106.2.6. High relevance — show source text
(1) The space(s) containing the machinery is (are) separated from other occupancies by tight construction with tightfitting doors.
(2) Access is restricted to authorized personnel.
(3) Refrigerant detectors are installed with the sensing location and alarm level as required in refrigeration machinery rooms in accordance with Section 1106.2.6.
(4) Open flames and surfaces exceeding 800°F (427°C) shall not be permitted where a Group A2, B2, A3, or B3 refrigerant, is used.
(5) Electrical equipment that is in accordance with Class 1, Division 2, of NFPA 70 where the quantity of a Group A2, B2, A3, or B3 refrigerant in an independent circuit is capable of exceeding 25 percent of the lower flammability limit (LFL) upon release to the space based on the volume determined in accordance with Section 1104.2.1 through Section 1104.2.3.
(6) Refrigerant containing parts in systems exceeding 100 horsepower (74.6 kW) compressor drive power, except evaporators used for refrigeration or dehumidification, condensers used for heating, control and pressure-relief valves for either, low-probability pumps, and connecting piping, are located in a machinery room or outdoors.
[ASHRAE 15:7.2.2]
1104.5 Flammable Refrigerants. The total of Group A2, B2, A3, and B3 refrigerants, other than Group A2L and B2L refrigerants shall not exceed 1100 pounds (498.9 kg) without approval by the Authority Having Jurisdiction. Institutional Occupancies shall comply with Section 1104.3. Machinery rooms required in accordance with Section 1106.0 based on flammability shall be constructed and maintained in accordance with Section 1106.2.1 through Section 1106.2.6 and Section 1106.11 for Group A2L and B2L refrigerants. 1104.6 Group A2L Refrigerants for Human Comfort. High-probability systems using Group A2L refrigerants for human comfort applications shall comply with this section.
[ASHRAE 15:7.6]
1104.6.1 Refrigerant Concentration Limits. Occupied spaces shall comply with the releasable charge limitations of the equipment listing and ASHRAE 15. Unoccupied spaces with refrigerant containing equipment, not including continuous piping or tubing, shall comply with the releasable charge limitations of the equipment listing or Section 1104.6.4. {ASHRAE 15:7.6.1-7.6.1.2}
1104.6.2 Listing and Installation Requirements. Refrigeration systems shall be listed and shall be installed in accordance with listing, the manufacturer’s instructions, and any markings on the equipment restricting the installation. [ASHRAE 15:7.6.2]
1104.6.2.1 Nameplate. The nameplate required by Section 1115.5 shall include a symbol indicating that a flammable refrigerant is used, as specified by the product listing. [ASHRAE 15:7.6.2.1]
1104.6.2.2 Labeling. A label indicating a flammable refrigerant is used shall be placed adjacent to service ports and other locations where service involving components containing refrigerant is performed, as specified by the product listing.
CMC § 5802.1 High relevance — show source text
SECTION 5802—DEFINITIONS
5802.1 Definitions. The following terms are defined in Chapter 2:
FLAMMABLE GAS.
FLAMMABLE LIQUEFIED GAS.
GAS DETECTION SYSTEM.
GASEOUS HYDROGEN SYSTEM.
HYDROGEN FUEL GAS ROOM.
METAL HYDRIDE.
METAL HYDRIDE STORAGE SYSTEM.
SECTION 5803—GENERAL REQUIREMENTS
5803.1 Quantities not exceeding the maximum allowable quantity per control area. The storage and use of flammable gases in amounts not exceeding the maximum allowable quantity per control area indicated in Section 5003.1 shall be in accordance with Sections 5001, 5003, 5801 and 5803.
5803.1.1 Special limitations for indoor storage and use. Flammable gases shall not be stored or used in Group A, E, I or R occupancies or in offices in Group B occupancies.
Exceptions:
- Cylinders of nonliquefied compressed gases not exceeding a capacity of 250 cubic feet (7.08 m [3] ) or liquefied gases not exceeding a capacity of 40 pounds (18 kg) each at normal temperature and pressure (NTP) used for maintenance purposes, patient care or operation of equipment.
- Food service operations in accordance with Section 6103.2.1.7.
- Hydrogen gas systems located in a hydrogen fuel gas room constructed in accordance with Section 421 of the Califor- nia Building Code .
5803.1.1.1 Medical gases. Medical gas system supply cylinders shall be located in medical gas storage rooms or gas cabinets as set forth in Section 5306.
5803.1.1.2 Aggregate quantity. The aggregate quantities of flammable gases used for maintenance purposes and operation of equipment shall not exceed the maximum allowable quantity per control area indicated in Table 5003.1.1(1).
5803.1.2 Storage containers. Cylinders and pressure vessels for flammable gases shall be designed, constructed, installed, tested and maintained in accordance with Chapter 53.
2025 CALIFORNIA FIRE CODE 58-3
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
FLAMMABLE GASES AND FLAMMABLE CRYOGENIC FLUIDS
5803.1.3 Emergency shutoff. Compressed gas systems conveying flammable gases shall be provided with approved manual or automatic emergency shutoff valves that can be activated at each point of use and at each source.
5803.1.3.1 Shutoff at source. A manual or automatic fail-safe emergency shutoff valve shall be installed on supply piping at the cylinder or bulk source. Manual or automatic cylinder valves are allowed to be used as the required emergency shutoff valve where the source of supply is limited to unmanifolded cylinder sources.
5803.1.3.2 Shutoff at point of use. A manual or automatic emergency shutoff valve shall be installed on the supply piping at the point of use or at a point where the equipment using the gas is connected to the supply system.
5803.1.4 Ignition source control. Ignition sources in areas containing flammable gases in storage or in use shall be controlled in accordance with Section 5003.7.
Exception: Fuel gas systems connected to building service utilities in accordance with the International Fuel Gas Code .
CMC § 1.11. High relevance — show source text
- The California Code of Regulations (CCR), Title 19, Division 1 provisions that are found in the California Fire Code are a reprint from the current CCR, Title 19, Division 1 text for the code user’s convenience only. The scope, applicability and appeals procedures of CCR, Title 19, Division I remain the same. The state agency does not adopt sections identified by 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.
2025 CALIFORNIA FIRE CODE 53-1
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
53-2 2025 CALIFORNIA FIRE CODE
on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.
53 COMPRESSED GASES
User notes:
About this chapter: Chapter 53 regulates the storage, use and handling of all flammable and nonflammable compressed gases, such as those that are used in medical facilities, air separation plants, industrial plants, agricultural equipment and similar occupancies. Also, this chapter regulates inert gases, such as CO 2 used for enrichment and beverage dispensing, that although inert are considered asphyxiants and in larger amounts pose a life safety hazard. Standards for the design, construction and marking of compressed gas cylinders and pressure vessels are referenced. Compressed gases used in welding and cutting, cryogenic liquids and liquefied petroleum gases are also regulated under Chapters 35, 55 and 61, respectively. Compressed gases that are classified as hazardous materials are also regulated in Chapter 50, which includes general requirements.
SECTION 5301—GENERAL
5301.1 Scope. Storage, use and handling of compressed gases in compressed gas containers, cylinders, tanks and systems shall comply with this chapter and NFPA 55, including those gases regulated elsewhere in this code. Partially full compressed gas containers, cylinders or tanks containing residual gases shall be considered as full for the purposes of the controls required.
Liquefied natural gas for use as a vehicular fuel shall also comply with NFPA 52 and NFPA 59A.
Compressed gases classified as hazardous materials shall also comply with Chapter 50 for general requirements and chapters addressing specific hazards, including Chapters 58 (Flammable Gases and Flammable Cryogenic Fluids), 60 (Highly Toxic and Toxic Materials), 63 (Oxidizers, Oxidizing Gases and Oxidizing Cryogenic Fluids) and 64 (Pyrophoric Materials).
Compressed hydrogen (CH 2 ) shall also comply with the applicable portions of Chapters 23 and 58 of this code, the International Fuel Gas Code and NFPA 2.
Cutting and welding gases shall also comply with Chapter 35.
Exceptions:
Gases used as refrigerants in refrigeration systems (see Section 608).
Compressed natural gas (CNG) for use as a vehicular fuel shall comply with Chapter 23, the International Fuel Gas Code and NFPA 52.
Cryogenic fluids shall comply with Chapter 55.
LP-gas shall comply with Chapter 61 and the International Fuel Gas Code .
[California Code of Regulations, Title 19, Division 1, §3.18(a) and (b)] Hazardous Areas.
Frequently asked questions
Which single sentence tells me if Chapter 13 applies?
If your installation is one of the specific applications listed in § 1302.3, Chapter 13 does not apply — use the listed subsection that matches your case.
Are portable cylinder appliances always excluded?
Yes — portable LP‑Gas appliances and equipment not connected to a fixed fuel piping system are excluded by § 1302.3(1).
What if my project is at a small chemical plant?
If the gas is used in chemical production or reactions or the site is a “large integrated chemical plant” (or similar), § 1302.3(7) excludes it from Chapter 13 — verify the appropriate industrial standard.
Does Chapter 13 cover LNG or utility gas plants?
No. § 1302.3(8) excludes LP‑Gas installations at utility gas plants and § 1302.3(9) excludes LNG installations.
Where do I go if my application is excluded?
If excluded, follow the industry standard or code that specifically regulates that application (NFPA standards, utility rules, or other applicable codes) and check with the authority having jurisdiction. § 1302.3 itself lists the exclusions.
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