(a) Not more than 120 gallons of Category 1, 2, 3 and 4 flammable liquids may be stored in a storage cabinet. Of this total, not more than 60 gallons may be of Category 1, 2 and 3 flammable liquid. Not more than three such cabinets may be located in a single fire area, except that in an industrial occupancy additional cabinets may be located in the same fire area if the additional cabinet, or group of not more than three cabinets, is separated from any other cabinets or group of cabinets by at least 100 feet.
(b) Storage cabinets shall be designed and constructed to limit the internal temperature to not more than 325oF when subjected to a ten-minute fire test using the standard time temperature curve as set forth in Standard Methods of Fire Tests of Building Construction and Materials, NFPA No. 251-1972. All joints and seams shall remain tight and the door shall remain securely closed during the fire test. Cabinets shall be labeled in conspicuous lettering, “FLAMMABLE-KEEP FIRE AWAY.”
(1) Metal cabinets constructed in the following manner shall be deemed to be in compliance with (b). The bottom, top, door and sides of cabinet shall be at least No. 18 gage sheet iron and double walled with 1 1/2-inch air space. Joints shall be riveted, welded or made tight by some equally effective means. The door shall be provided with a three-point lock, and the door sill shall be raised at least two inches above the bottom of the cabinet.
(2) Wooden cabinets constructed in the following manner shall be deemed in compliance with (b). The bottom, sides and top shall be constructed of an approved grade of plywood at least 1-inch in thickness, which shall not break down or delaminate under fire conditions. All joints shall be rabbeted and shall be fastened in two directions with flathead wood screws. When more than one door is used, there shall be a rabbeted overlap of not less than 1-inch. Hinges shall be mounted in such a manner as to not lose their holding capacity due to loosening or burning out of the screws when subjected to the fire test.