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An inside storage room must be constructed to meet the required fire-resistive rating for their use. Their construction must comply with the test specifications set forth in NFPA 251 (1969), “Standard Methods of Fire Tests of Building Construction and Materials.”
If an automatic sprinkler system is provided, it must be designed and installed in an acceptable manner. Openings to other rooms or buildings must be provided with noncombustible liquid-tight raised sills or ramps at least four inches in height, or the floor in the storage area must be at least four inches below the surrounding floor. Openings mustl be provided with approved self-closing fire doors. The room must also be liquid-tight where the walls join the floor. A permissible alternative to the sill or ramp is an open-grated trench inside of the room which drains to a safe location.
Where other portions of the building or other properties are exposed, windows must be protected as set forth in NFPA 80 (1968), “Standard for Fire Doors and Windows,” which is incorporated by reference as specified in1910.6 for Class E or F openings.
Wood at least one inch nominal thickness may be used for shelving, racks, dunnage, scuffboards, floor overlay, and similar installations.