Overview
The Occupational Safety and Health Administration (OSHA) sets requirements for the maintenance, safeguards and operational features of exit routes. Every exit must either be clearly visible or the route to reach it must be clearly marked so that every occupant of every building or structure who is physically and mentally capable will know the direction of escape from any point. Each path of escape, in its entirety, is to be arranged or marked so that the way to an outside place of safety is unmistakable.
Every exit sign must have the word “Exit” in plainly legible letters not less than 6 inches high, with the thickness of the letters not less than 3/4 inch wide. There isnot a predetermined color for exit signs because they are to be distinctive in color and provide contrast with decorations, interior finish or other signs.
Any door, passage or stairway that is neither an exit nor a way of exit access, and which is located or arranged and could be mistaken for an exit, is to be identified by a sign reading “Not an Exit” or similar designation. A sign indicating its actual character, such as “To Basement,” “Storeroom,” “Closet” or the like, would be a good idea.
Every exit sign needs to be suitably illuminated by a reliable light source giving a value of not less than 5 foot-candles on the illuminated surface. Artificial lights giving illumination to exit signs other than the internally illuminated types shall have screens, discs or lenses of not less than 25 square inches made of translucent material to show red or other specified designating color on the side of the approach. There are not to be any brightly illuminated signs (for other than exit purposes), displays or objects in or near the line of vision to the required exit sign that would detract attention from the exit sign or cause it to not be noticed.
NFPA Life Safety Code (2009 edition) section 7.10.1.2.1 – Exits, other than the main exterior exit doors that obviously and clearly are identifiable as exits, must be marked by an approved sign that is readily visible from any direction of exit access.