Emergency Lighting Guide: Exit Signs
Are you opening a new business or planning a shiny, new remodel of an existing place of business? One of the things you'll have to consider—whether you want to or not—is emergency lighting. There's good news, however. Despite being a technical subject, federal guidelines on emergency lighting boil down to the contents of only two key documents: OSHA 29CFR and NFPA 101. If those sound like challenging reads, they are, but this introductory article should help you get started.
Because this is a relatively large and technical subject, we'll be splitting it into two parts: The first part, which you'll read today, deals with exit signs, while next week's article will deal with emergency lights.
Let's start with a question: How many exits does your place of business have? Every one of those exits will need an exit sign. The requirements here are simple. The exit sign must legibly state the word "EXIT" in letters at least 6 inches high and with a 0.75 inch stroke. (29CFR 1910.37(b)(7)). That's easy; in fact, you would be hard-pressed to find an exit sign in the United States that doesn't meet those requirements.
Unfortunately, that's the only easy part. There's no point in having an exit sign if your employees can't see it, is there? Your exit signs must be fully illuminated, either by an external light source or by internal illumination. Save yourself some trouble here and go with internal illumination. Using an external light source requires a whole new list of rules that, trust us, you don't have time for. Besides, with all the pre-approved, self-luminated exit sign options available—LED, Tritium, even photoluminescent (glow-in-the-dark)—why would you use anything else?
Though a little light goes a long way, even with the brightest exit sign, you've still got the problem of corners, hallways, and winding corridors. OSHA also requires that, unless the exit sign is in plain sight from every point in the building (good luck with that) you'll need additional signs with arrows that point the way the door (29CFR 1910.37(b)(4)). Fortunately, most every exit sign available today does double-duty as both an exit sign and a directional sign. To make your exit sign a directional sign, simply punch out the "chevrons" on either side of the unit and mount the sign to point in the appropriate direction. Only in very high-end "designer" exit signs will you need to order a special unit with pre-applied or glass etched directional arrows.
Speaking of "designer," there's no problem with injecting some aesthetic sensibility into your emergency lighting. Typical white thermoplastic exit signs work fine on white or off-white walls, but with darker walls (movie theaters being an obvious example) black thermoplastic units look much better. If you run a hotel or an upscale retail store, a unit with a brushed aluminum face or even an elegant edge-lit glass exit sign is a better option. Plus, with any LED exit sign you've got the choice of red or green letters.