NFPA Separation 3ft

5.3* Separation from Other Operations.

Spray booths shall be separated from other operations by a minimum distance of 915 mm (3 ft) or by a partition, wall, or floor/ceiling assembly having a minimum fire resistance rating of 1 hour. Multiple connected spray booths shall not be considered as “other operations.” Exception: As provided for in Section 13.3.

5.3.1 – Spray booths shall be installed so that all parts of the booth are readily accessible for cleaning.

5.3.2 – A clear space of not less than 915 mm (3 ft ) shall be maintained on all sides and above the spray booth. This clear space shall be kept free of any storage or combustible construction.

Exception No. 1: This requirement shall not prohibit locating a spray booth closer than 915 mm (3 ft) to or directly against an interior partition, wall, or floor/ceiling assembly that has a fire resistance rating of not less than 1 hour, provided the spray booth can be maintained and cleaned.
Exception No. 2: This requirement shall not prohibit locating a spray booth closer than 915 mm (3 ft) to an exterior wall or a roof assembly provided the wall or roof is constructed of noncombustible material and provided the spray booth can be maintained and cleaned.