In last week’s article, we discussed one major part of emergency lighting: Exit signs. In this week’s article, we’ll discuss the second part: Emergency lights. A note before you continue: Try not to confuse the terms “emergency lighting,” an overview of the entire topic, with “emergency lights,” a special light that comes on in the event of an emergency or power failure.
Like exit signs, emergency lights are a complex topic, yet also like exit signs, the regulations dealing with emergency lights come down to the same two important documents: OSHA 29CFR and NFPA 101, also known as the Life Safety Code.
The portion of OSHA 29CFR dealing with emergency lights (1910.37(b)) is relatively vague. It simply states, “Each exit route must be adequately lighted so that an employee with normal vision can see along the exit route.” NFPA 101, on the other hand, is much more specific. In section 18.104.22.168, it states:
- The emergency light must provide illumination for no less than 1-1/2 hours.
- The initial illumination of the emergency light must be an average of 1 footcandle (10.8 lux).
If you are unfamiliar with footcandles, essentially what the NFPA’s requires is that the light cast on any one square foot of an exit pathway must be equal to one lumen or more (a footcandle is equal to one lumen per square foot). This is something you’ll need to consider when choosing your emergency lights and why many of our lights include photometric charts. An emergency light with typical 5 watt tungsten heads may be appropriate for typical applications, but in many cases, you may need one with Halogen heads or even a special high wattage emergency light.
NFPA 101 also includes specific language about testing your emergency lights. Section 7.9.3 states:
- A hard-wired emergency light must be tested monthly for a minimum of 30 seconds.
- A fully battery-operated emergency light must be tested yearly for a minimum of 1-1/2 hours.
For the sake of convenience, not to mention safety, we highly recommend using self-testing emergency lights. These units continuously monitor the input voltage to the fixture as well as the condition of the battery backup. Should the fixture fail a test, an indicator light will signal that it needs to be serviced. At that point, you can choose whether you need to troubleshoot the input power, replace the emergency light battery, or replace the fixture altogether.
Items not covered in NFPA 101 but still worth considering include remote capability, emergency ballasts, and aesthetic considerations. Remote capability allows you to connect multiple emergency lights, exit signs, or remote heads together, which will all trigger in the event of an emergency. Emergency ballasts keep fluorescent lights operational in the event of a power failure. Finally, you may want to consider the color and style of the emergency light you choose; after all, it will become a part of your décor.