The applicable code standard for "above-the-door" emergency exit signs is UL Standard 924 – Emergency Lighting and Power Equipment.  In July, 2001, Underwriters Laboratories published UL Standard 924 Supplement SG.  This revised standard details more stringent performance, durability and legibility criteria to which a Photoluminescent exit sign must meet to be certified in conformance with UL 924.  Above-the-door photoluminescent exit signs listed in conformity with the UL 924 standard as it existed prior to July 11, 2001 are no longer valid.

 

There are misleading claims in the marketplace regarding "UL listed" exit signs.  This is particularly true with respect to photoluminescent technology.  Many of these signs, while "UL listed", are listed to be in compliance with UL Standard 1994 - Luminous Egress Path Marking Systems.  Signs listed under this Standard are not code recognized for above door installations.

 

The Uniform Building Code (UBC), the Uniform Fire Code (UFC), the International Building Code (IBC), the BOCA National Building Code (NBC) and the Standard Building Code (SBC) incorporate UL Standard 924.