J. J. Keller Advantage

Exit signs don't have to be self-illuminated, but they should be visible at all times. In some cases, this might require additional lighting, such as a directional light pointing on the sign. Beyond that, OSHA just says that exit signs must be illuminated (see the regulations below) but that doesn't necessarily require additional lighting directed onto the sign. The only letter of interpretation OSHA has is from 1976 (and since archived) but it did say that separate lighting wasn't required if ambient light was sufficient. 1910.37(b)(6) Each exit sign must be illuminated to a surface value of at least five foot-candles (54 lux) by a reliable light source and be distinctive in color. Self-luminous or electroluminescent signs that have a minimum luminance surface value of at least .06 footlamberts (0.21 cd/m2) are permitted. 1910.37(b)(7) Each exit sign must have the word "Exit" in plainly legible letters not less than six inches (15.2 cm) high, with the principal strokes of the letters in the word "Exit" not less than three-fourths of an inch (1.9 cm) wide.