San Francisco Fire Code § 325.6 Battery Charging Areas

Powered Mobility Devices and lithium-ion batteries used in such devices shall be charged in a suitable indoor room or area, or outdoor location, that, in either location:

(a) Has sufficient natural or mechanical ventilation in accordance with the Mechanical Code to prevent the accumulation of any flammable or other gases that may be discharged during normal charging operations;

(b) For the charging of Powered Mobility Devices with attached or enclosed batteries, has an adequate electrical supply and a sufficient number of electrical receptacles to allow each device to be directly connected to an electrical receptacle. Extension cords and power strips shall not be used. A minimum of 3 feet (914 mm) shall be maintained between each Powered Mobility Device during charging operations. Subject to the approval of the Fire Department, the minimum 3 feet (914 mm) separation distance while charging multiple Powered Mobility Devices may be reduced to a minimum of 6 inches (152 mm) if the Powered Mobility Device is UL 2272 listed, contains a UL 2271 listed battery tested and certified by an accredited laboratory, and such battery is contained in a completely enclosed noncombustible compartment within the Powered Mobility Device that has been tested and certified by an accredited laboratory;

(c) For the charging of detached battery packs or other removable storage batteries, has an adequate electrical supply and a sufficient number of electrical receptacles to allow the charging equipment for battery packs and other removable storage batteries to be directly connected to an electrical receptacle. Extension cords and power strips shall not be used. Battery packs and other removable storage batteries shall not be stacked or charged in an enclosed cabinet unless the cabinet is a Battery Cabinet approved by the Fire Department. Except as otherwise approved by the Fire Department, a minimum distance of 2 feet (610 mm) shall be maintained between each battery pack or other removable storage battery during charging operations, provided that the aggregate energy capacity of battery packs or other removable storage batteries that can be simultaneously charged in a single Fire Area does not exceed 20 kWh. A minimum distance of 3 feet (914 mm) shall be maintained between each battery pack or other removable storage battery during charging operations if the aggregate energy capacity exceeds 20 kWh. The aggregate energy capacity of battery packs or other removable batteries that can be simultaneously charged in a single fire area shall not exceed 50 kWh. The minimum separation distance requirements of this subsection (c) shall not apply to battery packs or other removable storage batteries during storage or charging within a Battery Cabinet. Each approved Battery Cabinet shall be considered a single Fire Area with an aggregate energy capacity not exceeding 50kWh;

(d) Is not used for the storage of flammable or combustible liquids, combustible waste, or hazardous materials; (e) Is separated by:

(1) A fire barrier with a minimum one-hour fire-resistance rating, or enclosure within Battery Cabinet, from areas in which repairs or other servicing are conducted on the battery or other electrical components of the Powered Mobility Device in a Group B, R-1, R-2, F, or S occupancy; or

(2) In an M occupancy, a minimum distance of at least 10 feet (3048 mm) from areas where Powered Mobility Devices are displayed for retail sale, stored, or where repairs or other servicing are conducted on the battery or other electrical components of the Powered Mobility Device, and where each Powered Mobility Device for sale is a SafetyCertified Powered Mobility Device.

(f) Where five or more Powered Mobility Devices, detached battery packs, or other removable storage batteries are being charged at a single indoor location, separated by a fire barrier that encloses the entire space with a minimum one-hour fire-resistance rating; is separated within the enclosure of a Battery Cabinet; or in an M occupancy, is separated by a minimum distance of 10 feet (3048 mm) from areas where Powered Mobility Devices are displayed for sale. The building or occupancy shall be equipped with a fire sprinkler system complying with Section 903.3.1.1 of the Fire Code, an automatic fire detection and alarm system complying with Section 907 of the Fire Code and have one or more smoke detectors. If the ambient temperature of the room during battery charging operations exceeds the limitations set forth in the manufacturer’s instructions or the equipment listing, the room or area shall be temperature controlled to prevent over-heating or other unsafe battery condition; and

(g) It is provided with a portable fire extinguisher complying with the requirements of Section 906 of the Fire Code and having a minimum 4-A:20-B:C rating.