CRC · California Residential Code

Where does the CRC address stationary engine generators and fuel cell power systems?

In plain terms: the California Residential Code regulates permanently installed generators in **§ R331** — they must be **UL‑listed** and tied into your home's wiring only with a **listed transfer switch**, and installed per the listing, manufacturer instructions and the California Electrical Code. Stationary fuel cell systems are addressed in **§ R332**, which tells you to follow **Section 1206 of the California Fire Code** for the technical requirements.

Last reviewed: July 6, 2026

What the code requires — 2–4 sentences

The California Residential Code addresses stationary engine generators in § R331 and requires they be listed to UL 2200 and connected to premise wiring by a listed transfer switch; installation must follow the listing, the manufacturer’s instructions and the California Electrical Code (see § R331.1 and § R331.2) .
Stationary fuel cell power systems are governed by § R332, which requires compliance with Section 1206 of the California Fire Code (see § R332.1) .

The single most important rule: stationary generators must be UL‑listed and tied into the premises wiring only through a listed transfer switch; fuel cell systems installed at a residence must follow the Fire Code Section 1206 instructions.


Requirements in detail

Key defined terms (first mention)

  • Stationary engine generators — covered by § R331 (see § R331.1 and § R331.2) .
  • Stationary fuel cell power systems — covered by § R332 (see § R332.1) and are required to comply with the California Fire Code, Section 1206 .
  • Listed — equipment tested/listed to a recognized standard (e.g., UL 2200 for stationary engine generators) as required by § R331.1 .
  • Listed transfer switch — required method to connect a stationary engine generator to the building electrical system per § R331.1 .

Decision‑relevant table

Decision dimension Requirement / value Code Reference
Generator listing standard UL 2200 (generator must be listed and labeled) § R331.1
Connection to premise wiring Connection must be by a listed transfer switch § R331.1
Installation authority & documentation Installed in an approved location and per the listing, manufacturer’s instructions, and the California Electrical Code § R331.2
Fuel cell systems compliance Stationary fuel cell power systems must comply with Section 1206 of the California Fire Code § R332.1 (referencing Fire Code § 1206)

Notes about cross‑references

  • § R331 references testing/listing (UL 2200) and the California Electrical Code for installation and transfer‑switch connection; the CRC text does not restate the detailed electrical installation rules — those are in the California Electrical Code and in the equipment listing/manufacturer instructions (§ R331.1, § R331.2) .
  • § R332 defers technical requirements for stationary fuel cell power systems to the California Fire Code (Section 1206); the CRC itself does not reproduce the Fire Code provisions consult Fire Code § 1206 for siting, ventilation, exhaust, fuel supply, fire‑safety, and other technical requirements .

Exceptions & special cases

  • The CRC sections R331 and R332, as written, do not list exceptions or size thresholds within the Residential Code text itself; they require listing and that installations follow referenced standards and codes (manufacturer instructions, California Electrical Code, and Fire Code § 1206) .
  • Because each generator or fuel‑cell product may have particular listing conditions or manufacturer limitations, the listing and manufacturer instructions are the place to find product‑specific exceptions — and the CRC explicitly requires following those documents under § R331.2 .
  • For the technical sizing, ventilation, fuel‑piping, or other hazard controls for fuel cells you must consult California Fire Code § 1206 (referred-to by § R332.1) — the CRC does not contain those technical limits itself .

Common mistakes

  • Assuming a portable or non‑listed generator meets the requirement — § R331.1 requires UL 2200 listing for stationary engine generators; portable units typically are not UL 2200‑listed for stationary installation .
  • Hard‑wiring a generator into the premises wiring without a listed transfer switch — the CRC requires the transfer switch connection method under § R331.1 .
  • Ignoring the manufacturer’s installation instructions and the California Electrical Code — § R331.2 makes compliance with listing, manufacturer instructions and the Electrical Code mandatory .
  • Treating the CRC as the sole authority for fuel‑cell installations — § R332.1 requires following Fire Code § 1206 for fuel cell requirements, so relying only on CRC text is incomplete .

Worked example

Scenario: A homeowner plans to install a permanently sited, natural‑gas‑fired, 12 kW standby generator to serve a single‑family home.

  • What the CRC requires: the generator must be listed and labeled in accordance with UL 2200, and the connection to the home’s wiring must be made by a listed transfer switch (per § R331.1) .
  • Installation rules: the unit must be installed in an approved location and in accordance with the generator listing, the manufacturer’s installation instructions, and the California Electrical Code (per § R331.2) .
  • Practical steps for the homeowner: specify a UL 2200‑listed stationary generator; specify a listed transfer switch sized for the generator and connected by a licensed electrician per the California Electrical Code; provide the installer with the manufacturer’s installation instructions and obtain approvals/permits showing compliance with the referenced codes (the CRC text requires those steps but does not itself detail transfer‑switch wiring or clearance distances — those appear in the Electrical Code and the product listing) .
    Note: if instead the homeowner were installing a stationary fuel cell system, the owner/installer must follow Fire Code Section 1206, as required by § R332.1 (the CRC points to that Fire Code section for the technical requirements) .

Related provisions

  • § R329 — Solar energy systems (CRC) — related when generators/fuel cells are part of hybrid energy systems .
  • § R330 — Energy storage systems (CRC) — relevant for installations where stationary generators or fuel cells work with battery systems .
  • California Electrical Code — referenced by § R331.2 for electrical installation details (see § R331.2) .
  • California Fire Code § 1206 — provides the detailed technical requirements for stationary fuel cell power systems that the CRC directs you to follow via § R332.1 .

Code references

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

  • CRC § 3-60 High relevance — show source text

    R315 Sleeping Lofts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-60

    R316 Habitable Attics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-61

    R317 Garages and Carports. . . . . . . . . . . . . . . . . . . . . . . . . . 3-61

    R318 Means of Egress . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-62

    R319 Emergency Escape and Rescue Openings . . . . . . . . 3-65

    R320 Handrails . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-67

    R321 Guards and Window Fall Protection . . . . . . . . . . . . . 3-67

    R322 Accessibility . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-68

    R323 Elevators and Platform Lifts . . . . . . . . . . . . . . . . . . . . 3-68

    R324 Glazing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-68

    R325 Light, Ventilation and Heating . . . . . . . . . . . . . . . . . . 3-72

    R326 Sanitation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-73

    R327 Toilet, Bath and Shower Spaces. . . . . . . . . . . . . . . . . 3-73

    R328 Aging-in-Place Design and Fall Prevention . . . . . . . . 3-73

    R329 Solar Energy Systems . . . . . . . . . . . . . . . . . . . . . . . . . . 3-74

    R330 Energy Storage Systems . . . . . . . . . . . . . . . . . . . . . . . 3-76

    R331 Stationary Engine Generators. . . . . . . . . . . . . . . . . . . 3-79

    R332 Stationary Fuel Cell Power Systems . . . . . . . . . . . . . 3-79

    R333 Reserved . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-79

    R334 Construction Waste Reduction, Disposal and Recycling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-79

    R335 Special Provisions for Licensed 24-Hour Care Facilities in a Group R-3.1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-79

  • CRC § 3-73 High relevance — show source text

    R326 Sanitation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-73

    R327 Toilet, Bath and Shower Spaces. . . . . . . . . . . . . . . . . 3-73

    R328 Aging-in-Place Design and Fall Prevention . . . . . . . . 3-73

    R329 Solar Energy Systems . . . . . . . . . . . . . . . . . . . . . . . . . . 3-74

    R330 Energy Storage Systems . . . . . . . . . . . . . . . . . . . . . . . 3-76

    R331 Stationary Engine Generators. . . . . . . . . . . . . . . . . . . 3-79

    R332 Stationary Fuel Cell Power Systems . . . . . . . . . . . . . 3-79

    R333 Reserved . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-79

    R334 Construction Waste Reduction, Disposal and Recycling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-79

    R335 Special Provisions for Licensed 24-Hour Care Facilities in a Group R-3.1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-79

    R336 Large Family Day-Care Homes . . . . . . . . . . . . . . . . . . . 3-82

    R337 Materials and Construction Methods for Exterior

    Wildfire Exposure . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-83

    R338 Electric Vehicle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-83

    2025 CALIFORNIA RESIDENTIAL CODE xxi

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

    CONTENTS

    R339 Reserved . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-84

    R340 Pollutant Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-84

    CHAPTER 4 FOUNDATIONS . . . . . . . . . . . . . . . . . . . . . . . . . 4-3

    R401 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-3

    R402 Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-5

  • CRC § 1602.1 High relevance — show source text

    0
    1602.1
    1602.2||||||||||||||||||||||||| |Adopting Agency
    Adopt Entire Chapter
    Adopt Entire Chapter as
    amended (amended sections
    listed below)
    Adopt only those sections
    that are listed below
    Chapter/Section
    1602.0
    1602.1
    1602.2|||X|||||||||||||||||||||| |Adopting Agency
    Adopt Entire Chapter
    Adopt Entire Chapter as
    amended (amended sections
    listed below)
    Adopt only those sections
    that are listed below
    Chapter/Section
    1602.0
    1602.1
    1602.2|||X|||||||||||||||||||||| |Adopting Agency
    Adopt Entire Chapter
    Adopt Entire Chapter as
    amended (amended sections
    listed below)
    Adopt only those sections
    that are listed below
    Chapter/Section
    1602.0
    1602.1
    1602.2|||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.

    2025 CALIFORNIA MECHANICAL CODE 341

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    342 2025 CALIFORNIA MECHANICAL CODE

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    CHAPTER 16

    STATIONARY POWER PLANTS

    1601.0 Stationary Fuel Cell Power Plants.

    1601.1 General. Fuel cell power plants with a power output of less than 50 kW shall be listed in accordance with CSA/ANSI FC 1/CSA C22.2 No. 62282-3-100 and installed

    in accordance with the manufacturer’s instructions. Fuel cell power plants with a power output of greater than 50 kW shall be installed in accordance with NFPA 853. [NFPA 54:10.29]

    1602.0 Stationary Gas Engines and Generators and Gas Turbines .

    1602.1 Gas Engines . The installation of stationary gas engines shall conform to NFPA 37. [NFPA 54:10.22]

    1602.1.1 Connection to the Gas Supply Piping. Stationary gas engines shall not be rigidly connected to the gas supply piping. [NFPA 54:10.22.1]

    1602.2 Liquid-Fueled Engines and Gas Turbines. In accordance with California Building Code Section 442.1, the installation of liquid-fueled stationary internal combustion engines and gas turbines shall conform to NFPA 37.

    1602.3 Stationary Engine Generators. Stationary engine generators shall be tested in accordance with UL 2200, and shall be installed in accordance with NFPA 37 and the

    manufacturer’s installation instructions.

    2025 CALIFORNIA MECHANICAL CODE 343

  • CRC § 1501.0 High relevance — show source text

    1501.0 General. . . . . . . . . . . . . . . . . . . . . 339

    1501.1 Applicability. . . . . . . . . . . . . . . . . . 339

    1502.0 General. . . . . . . . . . . . . . . . . . . . . 339

    CHAPTER 16 STATIONARY POWER

    PLANTS . . . . . . . . . . . . . . . . . . . . 341

    1601.0 Stationary Fuel Cell Power Plants . . . . . . . . . . . . . . . . . . . . . . 343

    1601.1 General. . . . . . . . . . . . . . . . . . . . . 343

    1602.0 Stationary Gas Engines and Generators and Gas Turbines . . . 343

    1602.1 Gas Engines . . . . . . . . . . . . . . . . . 343

    1602.2 Liquid-Fueled Engines and Gas Turbines . . . . . . . . . . . . . . . . 343

    1602.3 Stationary Engine Generators . . . 343

    CHAPTER 17 GEOTHERMAL ENERGY

    SYSTEMS AND AMBIENT

    TEMPERATURE LOOPS. . . . . . . 345

    Part I General . . . . . . . . . . . . . . . . . . . . 347

    1701.0 General. . . . . . . . . . . . . . . . . . . . . 347

    1701.1 Applicability. . . . . . . . . . . . . . . . . . 347

    1701.2 Construction Documents . . . . . . . 347

    1701.3 Site Survey . . . . . . . . . . . . . . . . . . 347

    1701.4 Used Materials . . . . . . . . . . . . . . . 347

    1701.5 Contact with Building Material . . . 347

    1701.6 Strains and Stresses . . . . . . . . . . 347

    1701.7 Flood Hazard . . . . . . . . . . . . . . . . 347

    1701.8 Pipe Support. . . . . . . . . . . . . . . . . 347

    1701.9 Velocities . . . . . . . . . . . . . . . . . . . 347

    1701.10 Chemical Compatibility . . . . . . . . . 347

    1701.11 Heat Transfer Fluid. . . . . . . . . . . . 347

    1702.0 Groundwater Systems . . . . . . . . . 347

    1702.1 General. . . . . . . . . . . . . . . . . . . . . 347

    Table 1701.11.1 Water Quality . . . . . . . . . . . . . . . . 348

    1703.0 Design of Systems . . . . . . . . . . . . 348

    1703.1 Ground-Heat Exchanger Design . . . . . . . . . . . . . . . . . . . . . 348

  • CRC § 1402.1 High relevance — show source text

    1402.1 General. . . . . . . . . . . . . . . . . . . . . 335

    1403.0 Plans Required . . . . . . . . . . . . . . . 335

    1403.1 General. . . . . . . . . . . . . . . . . . . . . 335

    1404.0 Workmanship . . . . . . . . . . . . . . . . 335

    1404.1 General. . . . . . . . . . . . . . . . . . . . . 335

    1405.0 Inspections . . . . . . . . . . . . . . . . . . 335

    1405.1 General. . . . . . . . . . . . . . . . . . . . . 335

    1405.2 Required Inspections . . . . . . . . . . 335

    1405.3 Other Inspections . . . . . . . . . . . . . 335

    1406.0 Pipe, Tubing, and Fittings. . . . . . . 335

    1406.1 General. . . . . . . . . . . . . . . . . . . . . 335

    1406.2 Hazardous Process

    Piping (HPP). . . . . . . . . . . . . . . . . 335

    1406.3 Special Requirements for HPP Gases . . . . . . . . . . . . . . . . . . . . . . 336

    CHAPTER 15 SOLAR ENERGY SYSTEMS. . . . 337

    1501.0 General. . . . . . . . . . . . . . . . . . . . . 339

    1501.1 Applicability. . . . . . . . . . . . . . . . . . 339

    1502.0 General. . . . . . . . . . . . . . . . . . . . . 339

    CHAPTER 16 STATIONARY POWER

    PLANTS . . . . . . . . . . . . . . . . . . . . 341

    1601.0 Stationary Fuel Cell Power Plants . . . . . . . . . . . . . . . . . . . . . . 343

    1601.1 General. . . . . . . . . . . . . . . . . . . . . 343

    1602.0 Stationary Gas Engines and Generators and Gas Turbines . . . 343

    1602.1 Gas Engines . . . . . . . . . . . . . . . . . 343

    1602.2 Liquid-Fueled Engines and Gas Turbines . . . . . . . . . . . . . . . . 343

    1602.3 Stationary Engine Generators . . . 343

    CHAPTER 17 GEOTHERMAL ENERGY

    SYSTEMS AND AMBIENT

    TEMPERATURE LOOPS. . . . . . . 345

    Part I General . . . . . . . . . . . . . . . . . . . . 347

    1701.0 General. . . . . . . . . . . . . . . . . . . . . 347

  • CRC § 902.10 High relevance — show source text

    Burning appliances . . . . . . . . . . . . . . . . . . . . . . . 902.10 Chimney, combination

    gas- and solid-fuel. . . . . . . . . . . . . . . . . . . . 802.5.8.2 Cooking operations . . . . . . . . . . . . . . . . . . . . . . . . 517.0

    Furnace . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 904.11

    Room heaters . . . . . . . . . . . . . . . . . . . . . . . . . . . . 915.4

    Venting. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 801.3

    SPARK ARRESTERS

    Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 221.0

    Solid-fuel cooking operations . . . . . . . . . . . . . . . 517.1.6

    SPECIFIC APPLIANCES,

    INSTALLATION OF . . . . . . . . . . . . . . . . . . . . . . Chapter 9

    STANDARDS

    Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 221.0

    General . . . . . . . . . . . . . . . . . . . . . . . . . . 301.2, 302.1.2

    Fire-extinguishing systems. . . . . . . . . . . . . . . . . 513.2.2

    Fuel gas piping. . . . . . . . . . . . . . . . . . . . . . . . . . D 115.1

    Hydronics . . . . . . . . . . . . . 1203.2, 1207.3, Table 1210.1

    Oil-or liquid-fuel

    burning equipment. . . . . . . . . . . . . . . . . . . . . C 103.0 Referenced. . . . . . . . . . . . . . . . . . . . . . . . . . Chapter 18

    Steam and hot water boilers . . . . . . . . . . . . . . . . 1002.0

    STATIONARY

    Engine generators. . . . . . . . . . . . . . . . . . . . . . . . 1602.0

    Fuel Cell Power Plant . . . . . . . . . . . . . . . . 221.0, 1601.0

    Gas Engines . . . . . . . . . . . . . . . . . . . . . . . . . . . .1602.0

    588 2025 CALIFORNIA MECHANICAL CODE

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    INDEX

    STEAM AND HOT-WATER SYSTEMS (Hospitals) . . . .319.0

  • CRC § 1601.0 High relevance — show source text

    CHAPTER 16

    STATIONARY POWER PLANTS

    1601.0 Stationary Fuel Cell Power Plants.

    1601.1 General. Fuel cell power plants with a power output of less than 50 kW shall be listed in accordance with CSA/ANSI FC 1/CSA C22.2 No. 62282-3-100 and installed

    in accordance with the manufacturer’s instructions. Fuel cell power plants with a power output of greater than 50 kW shall be installed in accordance with NFPA 853. [NFPA 54:10.29]

    1602.0 Stationary Gas Engines and Generators and Gas Turbines .

    1602.1 Gas Engines . The installation of stationary gas engines shall conform to NFPA 37. [NFPA 54:10.22]

    1602.1.1 Connection to the Gas Supply Piping. Stationary gas engines shall not be rigidly connected to the gas supply piping. [NFPA 54:10.22.1]

    1602.2 Liquid-Fueled Engines and Gas Turbines. In accordance with California Building Code Section 442.1, the installation of liquid-fueled stationary internal combustion engines and gas turbines shall conform to NFPA 37.

    1602.3 Stationary Engine Generators. Stationary engine generators shall be tested in accordance with UL 2200, and shall be installed in accordance with NFPA 37 and the

    manufacturer’s installation instructions.

    2025 CALIFORNIA MECHANICAL CODE 343

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    344 2025 CALIFORNIA MECHANICAL CODE

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    CALIFORNIA MECHANICAL CODE – MATRIX ADOPTION TABLE

    CHAPTER 17 – GEOTHERMAL ENERGY SYSTEMS AND AMBIENT TEMPERATURE LOOPS

    (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.)

  • CRC § 2.2. High relevance — show source text

    (76 mm) embedment per barrier shall be used. Spacing between barriers shall be not greater than 36 inches (914 mm).

    2.2. Premanufactured wheel barriers shall be anchored in accordance with the manufacturer’s installation

    instructions.

    1. An approved method designed to resist an impact of 2,000 pounds per square foot (95 760 N/m [2] ) in the direction of travel at 24 inches (610 mm) above grade.

    R330.9 Ventilation. Indoor installations of ESS that produce hydrogen or other flammable gases during charging shall be provided with mechanical ventilation in accordance with the California Mechanical Code.

    R330.10 Electric vehicle use. The temporary use of an owner or occupant’s electric-powered vehicle to power a dwelling unit while parked in an attached or detached garage or outdoors shall comply with the vehicle manufacturer’s instructions and the California Electrical Code.

    R330.11 Documentation and labeling. The following information shall be provided:

    1. A copy of the manufacturer’s installation, operation, maintenance and decommissioning instructions shall be provided to the owner or placed in a conspicuous location near the ESS equipment.
    2. A label on the installed system containing the contact information for the qualified maintenance and service providers.

    R330.12 Toxic and highly toxic gas. ESS that have the potential to release toxic or highly toxic gas during charging, discharging and normal use conditions shall not be installed within Group R-3 or R-4 occupancies.

    SECTION R331—STATIONARY ENGINE GENERATORS

    R331.1 General. Stationary engine generators shall be listed and labeled in accordance with UL 2200 and shall comply with this section. The connection of stationary engine generators to the premise wiring system shall be by means of a listed transfer switch.

    R331.2 Installation. The installation of stationary engine generators shall be in an approved location and in accordance with the listing, the manufacturer’s installation instructions and the California Electrical Code.

    SECTION R332—STATIONARY FUEL CELL POWER SYSTEMS

    R332.1 General. Stationary fuel cell power systems in new and existing buildings and structures shall comply with Section 1206 of the California Fire Code .

    SECTION R333—RESERVED

    SECTION R334—CONSTRUCTION WASTE REDUCTION, DISPOSAL AND RECYCLING

    R334.1 Construction waste management. Recycle and/or salvage for reuse a minimum of 65 percent of the nonhazardous construction and demolition waste in accordance with the California Green Building Standards Code, Chapter 4, Division 4.4.

    SECTION R335—SPECIAL PROVISIONS FOR LICENSED 24-HOUR CARE FACILITIES IN A GROUP R-3.1

    R335.1 Scope. The provisions of this section shall apply to 24-hour care facilities in a Group R-3.1 occupancy licensed by a governmental

    agency.

    R335.2 General. The provisions in this section shall apply in addition to general requirements in this code.

    R335.2.1 Restraint shall not be practiced in a Group R-3.1 occupancy.

    Exception: Occupancies which meet all the requirements for a Group I-3 occupancy.

  • CRC § 4.4. High relevance — show source text

    R331.1 General. Stationary engine generators shall be listed and labeled in accordance with UL 2200 and shall comply with this section. The connection of stationary engine generators to the premise wiring system shall be by means of a listed transfer switch.

    R331.2 Installation. The installation of stationary engine generators shall be in an approved location and in accordance with the listing, the manufacturer’s installation instructions and the California Electrical Code.

    SECTION R332—STATIONARY FUEL CELL POWER SYSTEMS

    R332.1 General. Stationary fuel cell power systems in new and existing buildings and structures shall comply with Section 1206 of the California Fire Code .

    SECTION R333—RESERVED

    SECTION R334—CONSTRUCTION WASTE REDUCTION, DISPOSAL AND RECYCLING

    R334.1 Construction waste management. Recycle and/or salvage for reuse a minimum of 65 percent of the nonhazardous construction and demolition waste in accordance with the California Green Building Standards Code, Chapter 4, Division 4.4.

    SECTION R335—SPECIAL PROVISIONS FOR LICENSED 24-HOUR CARE FACILITIES IN A GROUP R-3.1

    R335.1 Scope. The provisions of this section shall apply to 24-hour care facilities in a Group R-3.1 occupancy licensed by a governmental

    agency.

    R335.2 General. The provisions in this section shall apply in addition to general requirements in this code.

    R335.2.1 Restraint shall not be practiced in a Group R-3.1 occupancy.

    Exception: Occupancies which meet all the requirements for a Group I-3 occupancy.

    R335.2.2 Pursuant to Health and Safety Code Section 13133, regulations of the state fire marshal pertaining to Occupancies classi- fied as Residential Facilities (RF) and Residential-care Facilities for the Elderly (RCFE) shall apply uniformly throughout the state and no city, county, city and county, including a charter city or charter county, or fire protection district shall adopt or enforce any ordi- nance or local rule or regulation relating to fire and panic safety which is inconsistent with these regulations. A city, county, city and county, including a charter city or charter county may pursuant to Health and Safety Code Section 13143.5, or a fire protection district may pursuant to Health and Safety Code Section 13869.7, adopt standards more stringent than those adopted by the state fire marshal that are reasonably necessary to accommodate local climate, geological or topographical conditions relating to roof cover- ings for Residential-care Facilities for the Elderly.

    Exception: Local regulations relating to roof coverings in facilities licensed as a Residential Care Facility for the Elderly (RCFE) per Health and Safety Code Section 13133.

    R335.3 Building height and area provisions.

    R335.3.1 Limitations six or less clients. Group R-3.1 occupancies where nonambulatory clients are housed above the first story, having more than two stories in height or having more than 3,000 square feet (279 m [2] ) of floor area above the first story shall not be of less than one-hour fire-resistance-rated construction throughout.

    In Group R-3.1 occupancies housing a bedridden client, the client sleeping room shall not be located above or below the first story.

  • CRC § 12-2 Medium relevance — show source text

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

    12-2 2025 CALIFORNIA FIRE CODE

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

    12 ENERGY SYSTEMS

    User notes:

    About this chapter: Chapter 12 was added to address the current energy systems found in this code, and is provided for the introduction of a wide range of systems to generate and store energy in, on and adjacent to buildings and facilities. The expansion of such energy systems is related to meeting today’s energy, environmental and economic challenges. Ensuring appropriate criteria to address the safety of such systems in building and fire codes is an important part of protecting the public at large, building occupants and emergency responders. More specifically, this chapter addresses standby and emergency power, portable generators, photovoltaic systems, fuel cell energy systems and energy storage systems.

    SECTION 1201—GENERAL

    1201.1 Scope. The provisions of this chapter shall apply to the installation, operation, maintenance, repair, retrofitting, testing, commissioning and decommissioning of energy systems used for generating or storing energy, including but not limited to energy storage systems under the exclusive control of an electric utility or lawfully designated agency. It shall not apply to equipment associated with the generation, control, transformation, transmission, or distribution of energy installations that is under the exclusive control of an electric utility or lawfully designated agency. Energy storage systems regulated by Section 1207 shall comply with this chapter, as appropriate, and NFPA 855.

    1201.2 Electrical wiring and equipment. Electrical wiring and equipment used in connection with energy systems shall be installed and maintained in accordance with this chapter, Section 603 and the California Electrical Code.

    1201.3 Mixed system installation. Where mixed systems are approved, the aggregate nameplate kWh energy of all energy storage systems in a fire area shall not exceed the maximum quantity specified for any of the energy systems in this chapter. Where required by the fire code official, a hazard mitigation analysis shall be provided and approved in accordance with Section 104.2.2 to evaluate any potential adverse interaction between the various energy systems and technologies.

    SECTION 1202—DEFINITIONS

    1202.1 Definitions. The following terms are defined in Chapter 2:

    BATTERY SYSTEM, STATIONARY STORAGE.

    BATTERY TYPES.

    CAPACITOR ENERGY STORAGE SYSTEM.

    CRITICAL CIRCUIT.

    EMERGENCY POWER SYSTEM.

    ENERGY STORAGE MANAGEMENT SYSTEMS.

    ENERGY STORAGE SYSTEM (ESS).

    ENERGY STORAGE SYSTEM, ELECTROCHEMICAL.

    ENERGY STORAGE SYSTEM, MOBILE.

    ENERGY STORAGE SYSTEM, WALK-IN UNIT.

    ENERGY STORAGE SYSTEM CABINET.

    ENERGY STORAGE SYSTEM COMMISSIONING.

    ENERGY STORAGE SYSTEM DECOMMISSIONING.

    FUEL CELL POWER SYSTEM, STATIONARY.

    PORTABLE GENERATOR.

    STANDBY POWER SYSTEM.

    SECTION 1203—EMERGENCY AND STANDBY POWER SYSTEMS

    1203.1 General. Emergency power systems and standby power systems required by this code or the California Building Code shall comply with Sections 1203.1.1 through 1203.1.9.

    1203.1.1 Stationary generators. Stationary emergency and standby power generators required by this code shall be listed in accordance with UL 2200.

    2025 CALIFORNIA FIRE CODE 12-3

  • CRC § 513.2.2 Medium relevance — show source text

    Fire-extinguishing systems. . . . . . . . . . . . . . . . . 513.2.2

    Fuel gas piping. . . . . . . . . . . . . . . . . . . . . . . . . . D 115.1

    Hydronics . . . . . . . . . . . . . 1203.2, 1207.3, Table 1210.1

    Oil-or liquid-fuel

    burning equipment. . . . . . . . . . . . . . . . . . . . . C 103.0 Referenced. . . . . . . . . . . . . . . . . . . . . . . . . . Chapter 18

    Steam and hot water boilers . . . . . . . . . . . . . . . . 1002.0

    STATIONARY

    Engine generators. . . . . . . . . . . . . . . . . . . . . . . . 1602.0

    Fuel Cell Power Plant . . . . . . . . . . . . . . . . 221.0, 1601.0

    Gas Engines . . . . . . . . . . . . . . . . . . . . . . . . . . . .1602.0

    588 2025 CALIFORNIA MECHANICAL CODE

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

    INDEX

    STEAM AND HOT-WATER SYSTEMS (Hospitals) . . . .319.0

    SUPPORT AND HANGERS . . . . . . . . . .313.0, Table 313.3

    SUSTAINABLE PRACTICES . . . . . . . . . . . . . . .Appendix E SWITCHES, ELECTRICAL SUPPLY LINE . . . . . . .903.2.7

    – T –

    TANKLESS WATER HEATERS . . . . . . . . . . . . . . . . .1203.3

    TERMINATION

    Chimneys . . . . . . . . . . . . . . . . . . . . .802.5.4, 802.5.4.2

    Environmental air ducts . . . . . . . . . . . . . . . . . . .502.2.1

    Exhaust duct systems,

    commercial kitchen . . . . . . . . . . . . . . . . .510.9, 519.5

    Exhaust

    ducts, clothes dryer . . . . . . . . . . . . . . . . . . . . . .504.4 Gas vents . . . . . . . . . . . . . . . . . . . . . . . .802.6, 802.6.1,

    802.7.2, 802.8, 802.8.1

    Product conveying ducts . . . . . . . . . . . . . . . . . .502.2.3 Type I hood exhaust system . . . . . . . . . . . . . . . . .510.9 Type II hood exhaust system . . . . . . . . . . . . . . . . .519.5

    TESTING

  • CRC § 1.6 Medium relevance — show source text

    Foam plastics R302.8 Insulation R302.10, R302.14 Penetrations R302.4

    Townhouse separation R302.2 Two-family dwellings R302.3 Under-stair protection R302.7 Wall and ceiling finishes R302.9 Fire-Separation Distance Exterior walls and wall projections R302.1 Ground-mounted photovoltaic systems R329.7, R329.8 Fixtures

    Clearance R327.1

    Flood protection R306.1.6 Plumbing fixture, general R326, R327 Flame Spread Index R302.10, R302.9 Flashing R703.4, R703.8.5, R903.2, R905 Flood Protection Plan Areas protected by the facilities of Central Valley Appendix CK Flood-Resistant Construction

    General and structural R301.2.4, R306 Floors

    Bathtub and shower R327.2 Concrete (on ground) R506 Loads R301, R501.2 Steel framing R505 Treated wood (on ground) R504

    Wood framing R502 Flue

    Area R1003.14, R1003.15 Lining R1003.11, R1003.12 Multiple R1003.13 Foam Plastics R303 Footings R403 Foundations Chapter 4 Cripple walls R602.10.9, R602.11.2, R602.9

    Frost protection R403.1.4.1 Inspection R109.1.1 Walls R404

    Frame

    Inspection R109.1.4 Frost Protection R507.3, R507.3.3, R1001.2 Fuel Cell Power System, Stationary R322 Fuel-Burning Appliances (see Appliances)

    Garbage Disposal (see Food-Waste Disposers) Garages R317, R330.8.1 Electric vehicle charging infrastructure R317.6 Protection of Energy Storage Systems R330.8

    Generators R331

    Girders R502.5 Glazing Aggregate area R325.1 Greenhouses R324.6.6 Protection of openings R301.2.1.2 Safety glazing at hazardous locations R324

    Site-built R324.5 Skylights and sloped glazing R324.6 Grade

    Of lumber R502.1.1, R602.1.1, R802.1.1 Grade Plane R101.2, R301.2.2.7, R316.3 Ground Floors (on ground) R504, R506 Guards or Guardrail R321, R324.4.4 Exterior R507.10 Guestroom (see Lodging House) Gypsum Board and Gypsum Panel Products R702.3

    Hallways R318.6 Hand Shower (see Shower) Handrails R318.7.8, R318.8.3, R320, R324.4.4 Alternating tread devices R318.7.12.2 Ship’s ladders R318.7.13.2 Hazardous Location R324

    Headers

    SIP R610.8

    Steel R603.6

    Wood R602.7

Frequently asked questions

Do stationary generators for residences always have to be UL 2200 listed?

Yes. The CRC requires stationary engine generators to be listed and labeled in accordance with UL 2200 under § R331.1 .

Can I hard‑wire a generator directly into my house panel?

No. § R331.1 requires the connection to the premise wiring to be made by a listed transfer switch; hard‑wiring without the listed transfer switch is not compliant with the CRC .

Where do I find the technical siting and fire‑safety rules for a residential fuel cell?

The CRC directs you to Section 1206 of the California Fire Code via § R332.1; that Fire Code section contains the siting, ventilation, exhaust and other technical fire‑safety requirements .

The generator manufacturer provided installation instructions — do I have to follow them?

Yes. § R331.2 explicitly requires installation in accordance with the listing, the manufacturer’s installation instructions, and the California Electrical Code .

Does the CRC state power thresholds (kW) for fuel cells or generators?

No. The CRC sections R331 and R332 do not set kW thresholds; § R332.1 instead refers you to Fire Code § 1206 for fuel cell technical rules, and § R331 requires listing and listed transfer‑switch connection but does not include size thresholds in the CRC text itself .

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