Cal. Code Regs. tit. 8, § 5474 – Design Considerations at Specific Locations.

(a) Where protective walls or roofs are provided, they shall be constructed of noncombustible materials.
(b) Where the enclosing sides adjoin each other, the enclosed area shall be properly ventilated.
(c) Electrical equipment within 15 feet shall be in accordance with the California Electrical Safety Orders for Class I, Division 2 locations. (Title 24, T8-5474)

1. Amendment filed 7-16-76; effective thirtieth day thereafter (Register 76, No. 29).