The Fail-Safe CFF is designed for use in horizontal or non-laminar air flow clean rooms. The enclosed and gasketed housing and one-piece, outside flanged door protect against infiltration of airborne bacteria. The die formed edges on the door frame and the hole-free design of the housing prevent air exchange between the fixture and plenum, allowing relamping without contamination of the clean areas. An emergency battery pack is available as an option. Suitable for I.E.S. Class 100 (M3.5) and above. It is UL/cUL listed for wet locations.