i've always wondered why most CFL's say "not for use in emergency exit signs" as long as they run horizontal or base down they should last a year or 2 probably
Most exit signs are base up though plus i don't think the cheesy electronics in the CFL can handle being on for more than a few hours at a time very well. too bad this isn't PL instead of CFL.
Yeah, CFLs usually fry in base up applications especially in enclosed lights like a exit sign. A PL of preheat T5 retrofit would be perfect for this or even a PL adapter would probably be better than a CFL if it fits.
i think a PL adapter or a retrofit kit would be better though unless this exit sign runs the lamps base down. if base up like i suspect, the electronics will fry from the lamp running 24/7. lamps aren't designed to burn 24/7. incandescents and usually non-electronically ballasted CFLs are fine though.