CFC · California Fire Code

What fire protection, suppression and large-scale fire-test requirements apply to ESS?

Homeowner summary: California requires batteries and energy storage systems to be listed to UL 9540 and—when the installation or size exceeds certain thresholds—be protected by sprinklers or alternate extinguishing systems validated by large‑scale UL 9540A testing so fires won’t spread between units or escape their enclosure.

Ask a question free See coverage

Last reviewed: July 6, 2026

What the code requires — 2–4 sentences

In California the fire code requires that rooms, areas and walk‑in units containing electrochemical ESS be protected by an automatic fire suppression system sized either by a prescriptive sprinkler density or by performance-based large‑scale testing. The prescriptive sprinkler minimum (for certain smaller systems) and the allowance for alternate extinguishing systems are given in § 1207.5.5, and the mandatory protocol for large‑scale fire testing is in § 1207.1.7. UL 9540 (listing for equipment) and UL 9540A (large‑scale fire test method) are the referenced standards used for equipment listing and testing under Chapter 12.

The single most important practical rule: where the code points to large‑scale fire testing, the owner/designer must provide a UL 9540A test report showing fires in one ESS will not propagate to an adjacent ESS and (where inside buildings or enclosures) will remain contained for the duration of the test. § 1207.1.7

Requirements in detail

1) When a suppression system is required

  • Automatic fire suppression is required for rooms, areas within buildings, and walk‑in units containing electrochemical ESS (see § 1207.5.5).
  • Special installations (rooftop walk‑in units, open parking garage walk‑in units, and certain other areas) reference § 1207.9.4 and still point to the requirements of § 1207.5.5.

2) Prescriptive sprinkler design (when it applies)

  • For ESS (groups) with a maximum stored energy capacity of 50 kWh or less, use an automatic sprinkler system per Section 903.3.1.1 with a minimum density of 0.3 gpm/ft² over the area of the room or a 2,500 ft² design area, whichever is smaller — unless a lower density is approved by large‑scale testing. § 1207.5.5(1)

3) Performance / test‑based design (when it applies)

  • For ESS units (groups) exceeding 50 kWh, the required sprinkler density must be based on large‑scale fire testing complying with § 1207.1.7 (UL 9540A). § 1207.5.5(2)
  • Alternative extinguishing systems (CO₂, water spray, water mist, clean agents, fixed aerosol, etc.) are permitted only when approved by the fire code official based on large‑scale fire testing in accordance with § 1207.1.7. § 1207.5.5(3)

4) Water‑reactive chemistries

  • ESS that use water‑reactive materials must be protected by an approved alternative automatic fire‑extinguishing system under Section 904, and that installation must be approved on the basis of large‑scale testing per § 1207.1.7. § 1207.5.5.1

5) Large‑scale fire testing requirement and use

  • Large‑scale fire testing on a representative ESS must be conducted in accordance with UL 9540A, performed or witnessed and reported by an approved testing laboratory. The test must show a fire in one ESS will not propagate to an adjacent ESS and, for building/enclosed installations, that the fire is contained within the room, enclosed area or walk‑in unit for the duration of the test. Test reports go to the fire code official for review under the permit/approval process. § 1207.1.7
  • UL 9540 is required for equipment listing: ESS shall be listed and labeled in accordance with UL 9540. § 1207.11.1

Decision‑relevant table (quick reference)

Decision item Value / threshold When it applies Code Reference
Prescriptive sprinkler density 0.3 gpm/ft² over room or 2,500 ft² ESS groups ≤ 50 kWh § 1207.5.5(1)
Performance‑based density Determined by large‑scale testing (UL 9540A) ESS groups > 50 kWh § 1207.5.5(2) and § 1207.1.7
Alternate extinguishing systems allowed NFPA 12, 15, 750, 2001, 2010, etc., only with UL 9540A test basis When approved by fire code official § 1207.5.5(3) and § 1207.1.7
Water‑reactive ESS Use approved alternative system per Section 904; approval requires UL 9540A Water‑reactive chemistries § 1207.5.5.1
Equipment listing UL 9540 listing required All ESS installations § 1207.11.1
Containment demonstration No propagation to adjacent ESS; contained for duration of UL 9540A test Where § 1207 requires testing § 1207.1.7
Max walk‑in enclosure size (outdoor) 53 ft × 8 ft × 9.5 ft (excl. bolt‑on HVAC) Outdoor walk‑in units § 1207.5.6
Clearance reductions allowed 3 ft where approved based on large‑scale testing Exterior clearances / egress / wall openings § 1207.8.3 and exceptions referencing § 1207.1.7

Exceptions & special cases

  • Residential small ESS: ESS listed to UL 9540 and marked “For use in residential dwelling units” have specific residential provisions and limited exceptions; many residential specifics are in Section 1207.11 (see § 1207.11.1).
  • Lead‑acid / Ni‑Cd limited exemptions: certain lead‑acid and nickel‑cadmium battery systems under communications utilities or substation control may be exempt from suppression requirements per the exceptions in § 1207.5.5.
  • Open parking garages: a fire suppression system may be omitted if large‑scale testing per § 1207.1.7 demonstrates the fire will not impact the exposures listed in § 1207.9.3. § 1207.9.4 (Exception)
  • Water‑reactive ESS: special handling and requirement for alternate systems (Section 904) and UL 9540A approval must be followed. § 1207.5.5.1

Common mistakes

  • Assuming the prescriptive sprinkler density (0.3 gpm/ft²) applies to all ESS: it applies only to ESS groups with ≤ 50 kWh; larger systems require testing‑based densities per § 1207.5.5(2).
  • Treating UL 9540 listing and UL 9540A testing as optional: UL 9540 is the required equipment listing (§ 1207.11.1) and UL 9540A is the required large‑scale test method where § 1207 calls for testing (§ 1207.1.7).
  • Using alternative extinguishing agents without a UL 9540A–based approval: the code requires fire code official approval based on large‑scale testing before alternate systems are accepted (§ 1207.5.5(3)).
  • Forgetting the containment requirement: UL 9540A testing must demonstrate no propagation to adjacent ESS and containment in the room/enclosure for the test duration — not just initial knockdown. § 1207.1.7

Worked example — rooftop walk‑in unit with 120 kWh of ESS

Scenario: A rooftop walk‑in ESS enclosure contains an electrochemical system with an aggregate stored energy capacity of 120 kWh.

Step 1 — Which rule applies? Because the group exceeds 50 kWh, the prescriptive 0.3 gpm/ft² density does not apply. The project must use a density and/or extinguishing approach based on large‑scale fire testing. § 1207.5.5(2)

Step 2 — Testing requirement: Provide a UL 9540A large‑scale test report performed/witnessed by an approved laboratory that demonstrates:

  • A fire in one ESS will not propagate to an adjacent ESS, and
  • The fire is contained within the walk‑in unit or room for the duration of the test. § 1207.1.7

Step 3 — Alternate extinguishing system option (if chosen): If the designer proposes a clean‑agent system per NFPA 2001 (or water mist, CO₂, etc.), the installation must be approved by the fire code official on the basis of the UL 9540A test showing the chosen agent/system achieves the containment/non‑propagation objective. § 1207.5.5(3)

Step 4 — Submit the UL 9540A test report to the fire code official with the permit package for review and approval per Section 104.2.2. § 1207.1.7

Related provisions (quick links to other relevant CFC sections)

  • § 1207.1.7 — Large‑scale fire test (UL 9540A requirement and approval use).
  • § 1207.5.5 — Fire suppression systems (prescriptive density, alternative systems).
  • § 1207.5.5.1 — Water‑reactive ESS special requirement.
  • § 1207.5.6 — Maximum outdoor walk‑in unit enclosure size.
  • § 1207.9.4 — Rooftop and open parking garage suppression system cross‑references.
  • § 1207.11.1 — Equipment listing requirement (UL 9540).

Code references

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

  • CFC § 1207.1.6.1 High relevance — show source text

    1207.1.6.1 Fault condition. The hazard mitigation analysis shall evaluate the consequences of the following failure modes. Only single failure modes shall be considered.

    1. A thermal runaway condition in a single electrochemical ESS unit.

    2. A mechanical failure of a nonelectrochemical ESS unit.

    3. Failure of any battery (energy) management system or fire protection system within the ESS equipment that is not covered by the product listing failure mode effects analysis (FMEA).

    4. Failure of any required protection system external to the ESS, including but not limited to ventilation (HVAC), exhaust ventilation, smoke detection, fire detection, gas detection or fire suppression system. (Material based on NFPA 855 2023 Ed.)

    1207.1.6.2 Analysis approval. The fire code official is authorized to approve the hazardous mitigation analysis provided that the consequences of the hazard mitigation analysis demonstrate:

    1. Fires will be contained within unoccupied ESS rooms or areas for the minimum duration of the fire-resistance-rated separations identified in Section 1207.7.4.
    2. Fires involving the ESS will allow occupants or the general public to evacuate to a safe location. (Material based on NFPA 855 2023 Ed.)

    1207.1.6.3 Additional protection measures. Construction, equipment and systems that are required for the ESS to comply with the hazardous mitigation analysis, including but not limited to those specifically described in Section 1207, shall be installed, maintained and tested in accordance with nationally recognized standards and specified design parameters.

    1207.1.7 Large-scale fire test. Where required elsewhere in Section 1207, large-scale fire testing shall be conducted on a representative ESS in accordance with UL 9540A. The testing shall be conducted or witnessed and reported by an approved testing laboratory and show that a fire involving one ESS will not propagate to an adjacent ESS, and where installed within buildings, enclosed areas and walk-in units will be contained within the room, enclosed area or walk-in unit for the duration of the test. The test report shall be provided to the fire code official for review and approval in accordance with Section 104.2.2. (Material based on NFPA 855 2023 Ed.)

    2025 CALIFORNIA FIRE CODE 12-11

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

    ENERGY SYSTEMS

    1207.1.8 Fire remediation. Where a fire or other event has damaged the ESS and ignition or re-ignition of the ESS is possible, the system owner, agent or lessee shall take the following actions, at their expense, to mitigate the hazard or remove damaged equipment from the premises to a safe location.

    1207.1.8.1 Fire mitigation personnel. Where, in the opinion of the fire code official, it is essential for public safety that trained personnel be on-site to respond to possible ignition or re-ignition of a damaged ESS, the system owner, agent or lessee shall dispatch within 15 minutes one or more fire mitigation personnel to the premise, as required and approved, at their expense. These personnel shall remain on duty continuously after the fire department leaves the premise until the damaged energy storage equipment is removed from the premises, or earlier if the fire code official indicates the public safety hazard has been abated. (Material based on NFPA 855 2023 Ed.)

  • CFC § 1207.1.7. High relevance — show source text

    1. Lot lines.

    2. Public ways.

    3. Stored combustible materials.

    4. Locations where motor vehicles can be parked.

    5. Hazardous materials.

    6. Other exposure hazards.

    Exceptions:

    1. Clearances are permitted to be reduced to 3 feet (914 mm) where a 1-hour free-standing fire barrier suitable for exterior use and extending 5 feet (1524 mm) above and 5 feet (1524 mm) beyond the physical boundary of the ESS installation is provided to protect the exposure.
    2. Clearances are permitted to be reduced to 3 feet (914 mm) where a weatherproof enclosure constructed of noncombustible materials is provided over the ESS, and it has been demonstrated that a fire within the enclosure will not ignite combustible materials outside the enclosure based on large-scale fire testing complying with Section 1207.1.7. (Material based on NFPA 855 2023 Ed.)

    1207.9.4 Fire suppression systems. ESS located in walk-in units on rooftops or in walk-in units in open parking garages shall be provided with automatic fire suppression systems within the ESS enclosure in accordance with Section 1207.5.5. Areas containing ESS other than walk-in units in open parking structures on levels not open above to the sky shall be provided with an automatic fire suppression system complying with Section 1207.5.5.

    Exception: A fire suppression system is not required in open parking garages if large-scale fire testing complying with Section 1207.1.7 is provided that shows that a fire will not impact the exposures in Section 1207.9.3. (Material based on NFPA 855 2023 Ed.)

    1207.9.5 Rooftop installations. ESS and associated equipment that are located on rooftops and not enclosed by building construction shall comply with the following:

    1. Stairway access to the roof for emergency response and fire department personnel shall be provided either through a bulkhead from the interior of the building or a stairway on the exterior of the building.
    2. Service walkways at least 5 feet (1524 mm) in width shall be provided for service and emergency personnel from the point of access to the roof to the system.

    2025 CALIFORNIA FIRE CODE 12-21

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

    ENERGY SYSTEMS

    1. ESS and associated equipment shall be located from the edge of the roof a distance equal to at least the height of the system, equipment or component but not less than 5 feet (1524 mm).
    2. The roofing materials under and within 5 feet (1524 mm) horizontally from an ESS or associated equipment shall be noncombustible or shall have a Class A rating when tested in accordance with ASTM E108 or UL 790.
    3. A Class I standpipe outlet shall be installed at an approved location on the roof level of the building or in the stairway bulkhead at the top level.
    4. The ESS shall be the minimum of 10 feet (3048 mm) from the fire service access point on the rooftop. (Material based on NFPA 855 2023 Ed.)

    1207.9.6 Open parking garages. ESS and associated equipment that are located in open parking garages shall comply with all of the following:

    1. ESS shall not be located within 50 feet (15 240 mm) of air inlets for building HVAC systems.
  • CFC § 903.3.1.1 High relevance — show source text

    ** Rooms and areas within buildings and walk-in units containing electrochemical ESS shall be protected by an automatic fire suppression system designed and installed in accordance with one of the following:

    1. Automatic sprinkler systems designed and installed in accordance with Section 903.3.1.1 for ESS units (groups) with a maximum stored energy capacity of 50 kWh, as described in Section 1207.5.1, shall be designed with a minimum density of 0.3 gpm/ft [2] (1.14 L/min) based over the area of the room or 2,500 square-foot (232 m [2] ) design area, whichever is smaller, unless a lower density is approved based on large-scale fire testing in accordance with Section 1207.1.7.
    2. Automatic sprinkler systems designed and installed in accordance with Section 903.3.1.1 for ESS units (groups) exceeding 50 kWh shall use a density based on large-scale fire testing complying with Section 1207.1.7.
    3. The following alternative automatic fire-extinguishing systems designed and installed in accordance with Section 904, provided that the installation is approved by the fire code official based on large-scale fire testing complying with Section 1207.1.7:

    3.1. NFPA 12, Standard on Carbon Dioxide Extinguishing Systems . 3.2. NFPA 15, Standard for Water Spray Fixed Systems for Fire Protection . 3.3. NFPA 750, Standard on Water Mist Fire Protection Systems . 3.4. NFPA 2001, Standard on Clean Agent Fire-Extinguishing Systems . 3.5. NFPA 2010, Standard for Fixed Aerosol Fire-Extinguishing Systems . Exceptions:

    1. Fire suppression systems for lead-acid and nickel-cadmium battery systems at facilities under the exclusive control of communications utilities that operate at less than 50 VAC and 60 VDC shall be provided where required by NFPA 76.
    2. Lead-acid and nickel-cadmium systems that are used for DC power for control of substations and control or safe shutdown of generating stations under the exclusive control of the electric utility, and located outdoors or in building spaces used exclusively for such installations, shall not be required to have a fire suppression system installed.
    3. Lead-acid battery systems in uninterruptable power supplies listed and labeled in accordance with UL 1778, utilized for standby power applications, which is limited to not more than 10 percent of the floor area on the floor on which the ESS is located, shall not be required to have a fire suppression system. (Material based on NFPA 855 2023 Ed.)

    12-16 2025 CALIFORNIA FIRE CODE

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

    ENERGY SYSTEMS

    1207.5.5.1 Water-reactive systems. Electrochemical ESS that utilize water-reactive materials shall be protected by an approved alternative automatic fire-extinguishing system in accordance with Section 904, where the installation is approved by the fire code official based on large-scale fire testing complying with Section 1207.1.7. 1207.5.6 Maximum enclosure size. Outdoor walk-in units housing ESS shall not exceed 53 feet by 8 feet by 9.5 feet high (16 154 mm × 2438 mm × 2896 mm), not including bolt-on HVAC and related equipment, as approved.

  • CFC § 1207.5.4 High relevance — show source text

    1. Where approved, installations shall be permitted in underground vaults complying with the California Electrical Code, Article 450, Part III.

    2. Where approved by the fire code official, installations shall be permitted on higher and lower floors. 1207.5.4 Fire detection. An approved automatic smoke detection system or radiant energy-sensing fire detection system complying with Section 907.2 shall be installed in rooms, indoor areas and walk-in units containing electrochemical ESS. An approved radiant energy-sensing fire detection system shall be installed to protect open parking garage and rooftop installations. Alarm signals from detection systems shall be transmitted to a central station, proprietary or remote station service in accordance with NFPA 72, or where approved to a constantly attended location. Exception: Normally unoccupied, remote stand-alone telecommunications structures with a gross floor area of less than 1,500 square feet (139 m [2] ) utilizing lead-acid or nickel-cadmium batteries shall not be required to have a fire detection system installed. (Material based on NFPA 855 2023 Ed.)

    1207.5.4.1 System status. Lead-acid and nickel-cadmium battery systems that are used for DC power for control of substations and control or safe shutdown of generating stations under the exclusive control of the electric utility, and located outdoors or in building spaces used exclusively for such installations, shall be allowed to use the process control system to monitor the smoke or radiant energy-sensing fire detectors required in Section 1207.5.4. (Material based on NFPA 855 2023 Ed.) 1207.5.5 Fire suppression systems. Rooms and areas within buildings and walk-in units containing electrochemical ESS shall be protected by an automatic fire suppression system designed and installed in accordance with one of the following:

    1. Automatic sprinkler systems designed and installed in accordance with Section 903.3.1.1 for ESS units (groups) with a maximum stored energy capacity of 50 kWh, as described in Section 1207.5.1, shall be designed with a minimum density of 0.3 gpm/ft [2] (1.14 L/min) based over the area of the room or 2,500 square-foot (232 m [2] ) design area, whichever is smaller, unless a lower density is approved based on large-scale fire testing in accordance with Section 1207.1.7.
    2. Automatic sprinkler systems designed and installed in accordance with Section 903.3.1.1 for ESS units (groups) exceeding 50 kWh shall use a density based on large-scale fire testing complying with Section 1207.1.7.
    3. The following alternative automatic fire-extinguishing systems designed and installed in accordance with Section 904, provided that the installation is approved by the fire code official based on large-scale fire testing complying with Section 1207.1.7:

    3.1. NFPA 12, Standard on Carbon Dioxide Extinguishing Systems . 3.2. NFPA 15, Standard for Water Spray Fixed Systems for Fire Protection . 3.3. NFPA 750, Standard on Water Mist Fire Protection Systems . 3.4. NFPA 2001, Standard on Clean Agent Fire-Extinguishing Systems . 3.5. NFPA 2010, Standard for Fixed Aerosol Fire-Extinguishing Systems . Exceptions: 1.

  • CFC § 12-16 High relevance — show source text

    Exceptions:

    1. Fire suppression systems for lead-acid and nickel-cadmium battery systems at facilities under the exclusive control of communications utilities that operate at less than 50 VAC and 60 VDC shall be provided where required by NFPA 76.
    2. Lead-acid and nickel-cadmium systems that are used for DC power for control of substations and control or safe shutdown of generating stations under the exclusive control of the electric utility, and located outdoors or in building spaces used exclusively for such installations, shall not be required to have a fire suppression system installed.
    3. Lead-acid battery systems in uninterruptable power supplies listed and labeled in accordance with UL 1778, utilized for standby power applications, which is limited to not more than 10 percent of the floor area on the floor on which the ESS is located, shall not be required to have a fire suppression system. (Material based on NFPA 855 2023 Ed.)

    12-16 2025 CALIFORNIA FIRE CODE

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

    ENERGY SYSTEMS

    1207.5.5.1 Water-reactive systems. Electrochemical ESS that utilize water-reactive materials shall be protected by an approved alternative automatic fire-extinguishing system in accordance with Section 904, where the installation is approved by the fire code official based on large-scale fire testing complying with Section 1207.1.7. 1207.5.6 Maximum enclosure size. Outdoor walk-in units housing ESS shall not exceed 53 feet by 8 feet by 9.5 feet high (16 154 mm × 2438 mm × 2896 mm), not including bolt-on HVAC and related equipment, as approved. Outdoor walk-in units exceeding these limitations shall be considered indoor installations and comply with the requirements in Section 1207.7. (Material based on NFPA 855 2023 Ed.) 1207.5.7 Vegetation control. Areas within 10 feet (3048 mm) on each side of outdoor ESS shall be cleared of combustible vegetation and other combustible growth. Single specimens of trees, shrubbery or cultivated ground cover such as green grass, ivy, succulents or similar plants used as ground cover shall be permitted to be exempt provided that they do not form a means of readily transmitting fire. (Material based on NFPA 855 2023 Ed.) 1207.5.8 Means of egress separation. ESS located outdoors and in open parking garages shall be separated from any means of egress as required by the fire code official to ensure safe egress under fire conditions, but in no case less than 10 feet (3048 mm).

    Exception: The fire code official is authorized to approve a reduced separation distance if large-scale fire testing complying with Section 1207.1.7 is provided that shows that a fire involving the ESS will not adversely impact occupant egress. (Material based on NFPA 855 2023 Ed.)

    1207.6 Electrochemical ESS technology-specific protection. Electrochemical ESS installations shall comply with the requirements of this section in accordance with the applicable requirements of Table 1207.6. (Material based on NFPA 855 2023 Ed.)

    |TABLE 1207.

  • CFC § 1207.1.7. High relevance — show source text
    1. Clearances to buildings are permitted to be reduced to 3 feet (914 mm) where a weatherproof enclosure constructed of noncombustible materials is provided over the ESS, and it has been demonstrated that a fire within the enclosure will not ignite combustible materials outside the enclosure based on large-scale fire testing complying with Section 1207.1.7.

    1207.8.4 Exterior wall installations. ESS shall be permitted to be installed outdoors on exterior walls of buildings when all of the following conditions are met:

    1. The maximum energy capacity of individual ESS units shall not exceed 20 kWh.
    2. The ESS shall comply with applicable requirements in Section 1207.
    3. The ESS shall be installed in accordance with the manufacturer’s instructions and their listing.
    4. Individual ESS units shall be separated from each other by at least 3 feet (914 mm).
    5. The ESS shall be separated from doors, windows, operable openings into buildings or HVAC inlets by at least 5 feet (1524 mm).

    Exception: Where approved, smaller separation distances in Items 4 and 5 shall be permitted based on large-scale fire testing complying with Section 1207.1.7. (Material based on NFPA 855 2023 Ed.)

    12-20 2025 CALIFORNIA FIRE CODE

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

    ENERGY SYSTEMS

    1207.9 Special installations. Rooftop and open parking garage ESS installations shall comply with Sections 1207.9.1 through 1207.9.6.

    TABLE 1207.9—SPECIAL ESS INSTALLATIONS Col2 Col3 Col4
    COMPLIANCE REQUIRED COMPLIANCE REQUIRED ROOFTOPSa OPEN PARKING GARAGESb
    Feature Section Section Section
    All ESS installations 1207.4 Yes Yes
    Clearance to exposures 1207.9.3 Yes Yes
    Fire suppression systems 1207.9.4 Yes Yes
    Maximum allowable quantities 1207.5.2 Yes Yes
    Maximum enclosure size 1207.5.6 Yes Yes
    Means of egress separation 1207.5.8 Yes Yes
    Open parking garage installations 1207.9.6 No Yes
    Rooftop installations 1207.9.5 Yes No
    Size and separation 1207.5.1 Yes Yes
    Smoke and automatic fire detection 1207.5.4 Yes Yes
    Technology-specific protection 1207.6 Yes Yes
    a. See Section 1207.9.1.
    b. See Section 1207.9.2.    		 a. See Section 1207.9.1.
    b. See Section 1207.9.2.    		 a. See Section 1207.9.1.
    b. See Section 1207.9.2.    		 a. See Section 1207.9.1.
    b. See Section 1207.9.2.

    1207.9.1 Rooftop installations. For the purpose of Table 1207.9, rooftop ESS installations are those located on the roofs of buildings. (Material based on NFPA 855 2023 Ed.)

  • CFC § 1207.9.1. High relevance — show source text

    See Section 1207.9.1.
    b. See Section 1207.9.2.|a. See Section 1207.9.1.
    b. See Section 1207.9.2.|a. See Section 1207.9.1.
    b. See Section 1207.9.2.|a. See Section 1207.9.1.
    b. See Section 1207.9.2.|

    1207.9.1 Rooftop installations. For the purpose of Table 1207.9, rooftop ESS installations are those located on the roofs of buildings. (Material based on NFPA 855 2023 Ed.)

    1207.9.2 Open parking garage installations. For the purpose of Table 1207.9, open parking garage ESS installations are those located in a structure or portion of a structure that complies with Section 406.5 of the California Building Code . (Material based on NFPA 855 2023 Ed.)

    1207.9.3 Clearance to exposures. ESS located on rooftops and in open parking garages shall be separated by a minimum of 10 feet (3048 mm) from the following exposures:

    1. Buildings, except the building on which rooftop ESS is mounted.

    2. Any portion of the building on which a rooftop system is mounted that is elevated above the rooftop on which the system is installed.

    3. Lot lines.

    4. Public ways.

    5. Stored combustible materials.

    6. Locations where motor vehicles can be parked.

    7. Hazardous materials.

    8. Other exposure hazards.

    Exceptions:

    1. Clearances are permitted to be reduced to 3 feet (914 mm) where a 1-hour free-standing fire barrier suitable for exterior use and extending 5 feet (1524 mm) above and 5 feet (1524 mm) beyond the physical boundary of the ESS installation is provided to protect the exposure.
    2. Clearances are permitted to be reduced to 3 feet (914 mm) where a weatherproof enclosure constructed of noncombustible materials is provided over the ESS, and it has been demonstrated that a fire within the enclosure will not ignite combustible materials outside the enclosure based on large-scale fire testing complying with Section 1207.1.7. (Material based on NFPA 855 2023 Ed.)

    1207.9.4 Fire suppression systems. ESS located in walk-in units on rooftops or in walk-in units in open parking garages shall be provided with automatic fire suppression systems within the ESS enclosure in accordance with Section 1207.5.5. Areas containing ESS other than walk-in units in open parking structures on levels not open above to the sky shall be provided with an automatic fire suppression system complying with Section 1207.5.5.

    Exception: A fire suppression system is not required in open parking garages if large-scale fire testing complying with Section 1207.1.7 is provided that shows that a fire will not impact the exposures in Section 1207.9.3. (Material based on NFPA 855 2023 Ed.)

  • CFC § 1207.10.7.5. High relevance — show source text

    1. Location and layout diagram of the area in which the mobile ESS is to be deployed, including a scale diagram of all nearby exposures.

    2. Location and content of signage, including no smoking signs.

    3. Description of fencing to be provided around the ESS, including locking methods.

    4. Details on fire suppression, smoke and automatic fire detection, system monitoring, thermal management, exhaust ventilation and explosion control, if provided.

    5. For deployment, the intended duration of operation, including anticipated connection and disconnection times and dates.

    6. Location and description of local staging stops during transit to the deployment site. See Section 1207.10.7.5.

    7. Description of the temporary wiring, including connection methods, conductor type and size, and circuit overcurrent protection to be provided.

    8. Description of how fire suppression system connections to water supplies or extinguishing agents are to be provided.

    9. Contact information for personnel who are responsible for maintaining and servicing the equipment, and responding to emergencies as required by Section 1207.1.8.1. (Material based on NFPA 855 2023 Ed.)

    1207.10.5 Approved locations. Locations where mobile ESS are charged, stored and deployed shall be restricted to the locations established on the construction and operational permits. (Material based on NFPA 855 2023 Ed.)

    1207.10.6 Charging and storage. Installations where mobile ESS are charged and stored shall be treated as permanent ESS indoor or outdoor installations, and shall comply with the following sections, as applicable:

    1. Indoor charging and storage shall comply with Section 1207.7.
    2. Outdoor charging and storage shall comply with Section 1207.8.
    3. Charging and storage on rooftops and in open parking garages shall comply with Section 1207.9.

    Exceptions:

    1. Electrical connections shall be permitted to be made using temporary wiring complying with the manufacturer’s instructions, the UL 9540 listing and the California Electrical Code .
    2. Fire suppression system connections to the water supply shall be permitted to use approved temporary connections. (Material based on NFPA 855 2023 Ed.)

    1207.10.7 Deployed mobile ESS requirements. Deployed mobile ESS equipment and operations shall comply with this section and Table 1207.10. (Material based on NFPA 855 2023 Ed.)

    1207.10.7.1 Duration. The duration of mobile ESS deployment shall not exceed 30 days.

    Exceptions:

    1. Mobile ESS deployments that provide power for durations longer than 30 days shall comply with Section 1207.10.6.
    2. Mobile ESS deployments shall not exceed 180 days unless additional operational permits are obtained. (Material based on NFPA 855 2023 Ed.)

    1207.10.7.2 Restricted locations. Deployed mobile ESS operations shall not be located indoors, in covered parking garages, on rooftops, below grade or under building overhangs. (Material based on NFPA 855 2023 Ed.)

    1207.10.7.3 Clearance to exposures. Deployed mobile ESS shall be separated by a minimum of 10 feet (3048 mm) from the following exposures:

    1. Public ways.

    2. Buildings.

    3. Stored combustible materials.

    4. Hazardous materials.

    5. High-piled storage.

    6. Other exposure hazards.

  • CFC § 1207.1.5 High relevance — show source text

    A minimum of 1 foot vertically below the bottom edge of the ESS._
    3. A minimum of 8 feet vertically above the ESS, or to a non-combustible eave, whichever is less.
    The code official is authorized to approve reductions of installation requirements based on large-scale fire testing complying with Section 1207.1.5 of the California Fire Code.|For SI: 1 foot = 304.8 mm.
    a. Noncombustible wall surface shall extend in accordance with all the following:
    1. A minimum of 5 feet horizontally from the edge of the ESS.
    2. A minimum of 1 foot vertically below the bottom edge of the ESS.
    3. A minimum of 8 feet vertically above the ESS, or to a non-combustible eave, whichever is less.
    The code official is authorized to approve reductions of installation requirements based on large-scale fire testing complying with Section 1207.1.5 of the California Fire Code.|For SI: 1 foot = 304.8 mm.
    a. Noncombustible wall surface shall extend in accordance with all the following:
    1. A minimum of 5 feet horizontally from the edge of the ESS.
    2. A minimum of 1 foot vertically below the bottom edge of the ESS.
    3. A minimum of 8 feet vertically above the ESS, or to a non-combustible eave, whichever is less.
    The code official is authorized to approve reductions of installation requirements based on large-scale fire testing complying with Section 1207.1.5 of the California Fire Code.|

    R330.6 Electrical installation. ESS shall be installed in accordance with the California Electrical Code. Inverters shall be listed and labeled in accordance with UL 1741 or provided as part of the UL 9540 listing. Systems connected to the utility grid shall use inverters listed for utility interaction.

    R330.7 Fire detection. Rooms and areas within dwelling units, basements and attached garages in which ESS are installed shall be protected by smoke alarms in accordance with Section R310. A heat detector, listed and interconnected to the smoke alarms, shall be installed in locations within dwelling units and attached garages where smoke alarms cannot be installed based on their listing.

    [SFM] ESS installed in Group R-3 and townhomes shall comply with the following: 1. Rooms and areas within dwellings units, sleeping units, basements and attached garages in which ESS are installed shall be protected by smoke alarms in accordance with Section R314. 2. A listed heat alarm interconnected to the smoke alarms shall be installed in locations within dwelling units, sleeping units and attached garages where smoke alarms cannot be installed based on their listing.

    R330.8 Protection from impact. ESS installed in a location subject to vehicle damage in accordance with Section R330.8.1 or R330.8.2 shall be provided with impact protection in accordance with Section R328.8.3.

    R330.8.1 Garages. Where an ESS is installed in the normal driving path of vehicle travel within a garage, impact protection complying with Section R330.8.3 shall be provided. The normal driving path is a space between the garage vehicle opening and the interior face of the back wall to a height of 48 inches (1219 mm) above the finished floor.

  • CFC § 304.8 High relevance — show source text

    a_| |In detached garages and detached accessory structures|200|| |In detached garages and detached accessory structures|600|Detached garage or detached accessory structure is
    a minimum 10 feet away from property lines and
    dwellings.| |Outdoors on the ground|200|ESS is a minimum 3 feet away from property lines
    and dwellings.| |Outdoors on the ground|600|ESS is a minimum 10 feet away from property lines
    and dwellings.| |For SI: 1 foot = 304.8 mm
    a. Noncombustible wall surface shall extend in accordance with all the following:
    1. A minimum of 5 feet horizontally from the edge of the ESS.
    2. A minimum of 1 foot vertically below the bottom edge of the ESS.
    3. A minimum of 8 feet vertically above the ESS, or to a noncombustible eave, whichever is less.
    The code official is authorized to approve reductions of installation requirements based on large-scale fire testing complying with Section 1207.1.5.|For SI: 1 foot = 304.8 mm
    a. Noncombustible wall surface shall extend in accordance with all the following:
    1. A minimum of 5 feet horizontally from the edge of the ESS.
    2. A minimum of 1 foot vertically below the bottom edge of the ESS.
    3. A minimum of 8 feet vertically above the ESS, or to a noncombustible eave, whichever is less.
    The code official is authorized to approve reductions of installation requirements based on large-scale fire testing complying with Section 1207.1.5.|For SI: 1 foot = 304.8 mm
    a. Noncombustible wall surface shall extend in accordance with all the following:
    1. A minimum of 5 feet horizontally from the edge of the ESS.
    2. A minimum of 1 foot vertically below the bottom edge of the ESS.
    3. A minimum of 8 feet vertically above the ESS, or to a noncombustible eave, whichever is less.
    The code official is authorized to approve reductions of installation requirements based on large-scale fire testing complying with Section 1207.1.5.|

    12-24 2025 CALIFORNIA FIRE CODE

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

    ENERGY SYSTEMS

    1207.11.5 Electrical installation. ESS shall be installed in accordance with the California Electrical Code. Inverters shall be listed and labeled in accordance with UL 1741 or provided as part of the UL 9540 listing. Systems connected to the utility grid shall use inverters listed for utility interaction. (Material based on NFPA 855 2023 Ed.)

    1207.11.6 Fire detection. ESS installed in Group R-3 and R-4 occupancies shall comply with the following:

    1. Rooms and areas within dwelling units, sleeping units, basements and attached garages in which ESS are installed shall be protected by smoke alarms in accordance with Section 907.2.11.
    2. A listed heat alarm shall be installed in locations where smoke alarms cannot be installed based on their listing.
  • CFC § 1207.8.1. High relevance — show source text

    See Section 1207.8.1.
    b. See Section 1207.8.2.
    c. Where approved by the fire code official, fire suppression systems are permitted to be omitted.
    d. In outdoor walk-in units, spacing is not required between ESS units and the walls of the enclosure.|a. See Section 1207.8.1.
    b. See Section 1207.8.2.
    c. Where approved by the fire code official, fire suppression systems are permitted to be omitted.
    d. In outdoor walk-in units, spacing is not required between ESS units and the walls of the enclosure.|a. See Section 1207.8.1.
    b. See Section 1207.8.2.
    c. Where approved by the fire code official, fire suppression systems are permitted to be omitted.
    d. In outdoor walk-in units, spacing is not required between ESS units and the walls of the enclosure.|a. See Section 1207.8.1.
    b. See Section 1207.8.2.
    c. Where approved by the fire code official, fire suppression systems are permitted to be omitted.
    d. In outdoor walk-in units, spacing is not required between ESS units and the walls of the enclosure.|

    1207.8.1 Remote outdoor installations. For the purpose of Table 1207.8, remote outdoor installations include ESS located more than 100 feet (30 480 mm) from buildings, lot lines, public ways, stored combustible materials, hazardous materials, high-piled stock and other exposure hazards. (Material based on NFPA 855 2023 Ed.)

    1207.8.2 Installations near exposures. For the purpose of Table 1207.8, installations near exposures include all outdoor ESS installations that do not comply with Section 1207.8.1 remote outdoor location requirements. (Material based on NFPA 855 2023 Ed.)

    1207.8.3 Clearance to exposures. ESS located outdoors shall be separated by a minimum of 10 feet (3048 mm) from the following exposures:

    1. Lot lines.

    2. Public ways.

    3. Buildings.

    4. Stored combustible materials.

    5. Hazardous materials.

    6. High-piled stock.

    7. Other exposure hazards.

    Exceptions: (Material based on NFPA 855 2023 Ed.)

    1. Clearances are permitted to be reduced to 3 feet (914 mm) where a 1-hour free-standing fire barrier suitable for exterior use and extending 5 feet (1524 mm) above and 5 feet (1524 mm) beyond the physical boundary of the ESS installation is provided to protect the exposure.

    2. Clearances to buildings are permitted to be reduced to 3 feet (914 mm) where noncombustible exterior walls with no openings or combustible overhangs are provided on the wall adjacent to the ESS and the fire-resistance rating of the exterior wall is a minimum of 2 hours.

    3. Clearances to buildings are permitted to be reduced to 3 feet (914 mm) where a weatherproof enclosure constructed of noncombustible materials is provided over the ESS, and it has been demonstrated that a fire within the enclosure will not ignite combustible materials outside the enclosure based on large-scale fire testing complying with Section 1207.1.7.

  • CFC § 3.6 High relevance — show source text

    Exceptions:

    1. ESS listed and labeled in accordance with UL 9540 and marked “For use in residential dwelling units,” where installed in accordance with the manufacturer’s instructions and the California Electrical Code .

    2. ESS rated less than 1 kWh (3.6 megajoules).

    1207.11.1 Equipment listings. ESS shall be listed and labeled in accordance with UL 9540.

    1207.11.2 Installation. ESS shall be installed in accordance with the manufacturer’s instructions and their listing. (Material based on NFPA 855 2023 Ed.)

    1207.11.2.1 Spacing. Individual ESS units shall be separated from each other by at least 3 feet (914 mm) except where smaller separation distances are documented to be adequate based on large-scale fire testing complying with Section 1207.1.7.

    1207.11.3 Location. ESS shall be installed only in the following locations:

    1. Detached garages and detached accessory structures.
    2. Attached garages separated from the dwelling unit living space in accordance with Section R302.6.
    3. Outdoors or on the exterior side of exterior walls located not less than 3 feet (914 mm) from doors and windows directly entering the dwelling unit.
    4. Enclosed utility closets, basements, and storage or utility spaces within dwelling units and sleeping units with finished or noncombustible walls and ceilings. Walls and ceilings of unfinished wood-framed construction shall be provided with not less than [5] / 8 -inch (15.9 mm) Type X gypsum wallboard.

    ESS shall not be installed in sleeping rooms, or in closets or spaces opening directly into sleeping rooms. (Material based on NFPA 855 2023 Ed.)

    1207.11.4 Energy ratings. Individual ESS units shall have a maximum rating of 20 kWh. The ratings of the ESS in each loca- tion shall not exceed the ratings in Table 1207.11.4. The total aggregate ratings of ESS on the property shall not exceed 600 kWh.

    1. 40 kWh within utility closets, basements, and storage or utility spaces.

    2. 80 kWh in attached or detached garages and detached accessory structures.

    3. 80 kWh on exterior walls.

    4. 80 kWh outdoors on the ground.

    ESS installations exceeding the permitted individual or aggregate ratings shall be installed in accordance with Sections 1207.1 through 1207.9. (Material based on NFPA 855 2023 Ed.)

    TABLE 1207.11.4—MAXIMUM AGGREGATE RATINGS OF ESS Col2 Col3
    LOCATION MAXIMUM
    AGGREGATE
    RATINGS (kWh)    		 INSTALLATION REQUIREMENTS
    Within utility closets, basements, and storage or utility spaces located
    within dwellings    		 40
    In attached garages 80
    On or within 3 feet of exterior walls of dwellings and attached garages 100
    On or within 3 feet of exterior walls of dwellings and attached garages 200 Exterior walls and eaves are constructed with
    _noncombustible surfaces.

Frequently asked questions

When is UL 9540A testing required?

When Section 1207 specifically references large‑scale testing (for example for ESS groups > 50 kWh, or to approve alternate suppression methods or reduced clearances), testing must be conducted in accordance with UL 9540A and submitted to the fire code official as required by § 1207.1.7.

Can I use a clean‑agent system instead of sprinklers?

Yes — but only if the clean‑agent installation is approved by the fire code official based on large‑scale testing that meets the containment and non‑propagation objectives of § 1207.1.7 (see § 1207.5.5(3)).

Is the 0.3 gpm/ft² sprinkler density always valid?

No. The 0.3 gpm/ft² minimum applies only to ESS groups ≤ 50 kWh. For systems larger than 50 kWh, sprinkler density must be established using large‑scale testing per § 1207.1.7. § 1207.5.5(1)–(2)

Does UL 9540 listing replace the need for testing?

No. UL 9540 is the required equipment listing standard for ESS (§ 1207.11.1), but when § 1207 requires large‑scale testing (for performance demonstration, alternate agents, or reduced clearances), the testing protocol is UL 9540A and is still required.

Who reviews and approves the UL 9540A report?

The fire code official reviews the UL 9540A test report and is the authority to approve sprinkler densities, alternate extinguishing systems, or reduced clearances based on that testing, per § 1207.1.7 and the referenced permit/approval process.

More in California Fire Code

Ask about the CFC

Get cited, plain-English answers on the California Fire Code for your project — any code section, any scenario.

Start Free Trial

Related in the CFC

How much ESS energy is allowed per fire area and what separation/fire-resistance is required?

What are the rules for ESS cabinets, walk-in units and equipment enclosures?

What are the ventilation, thermal management, deflagration venting and detection requirements?

Design, Fire-Protection Systems & Safety Controls

California Fire Code