Emergency Lighting Installation Tips

A how to guide for ensuring that emergency lighting installations pass inspections the first time.

Emergency Lighting Installation Tips
provided by: 


After any emergency lighting installation is completed, the last step in the project is to have the inspector come in to approve the project. While most inspections go smoothly, the renewed emphasis on safety after 9/11 has prompted some inspectors to conduct a more thorough inspection of emergency lighting installations. The result is that in some instances the inspector will not approve the installation citing "does not meet the code." Here are a few tips you can use to make sure your inspection goes smoothly:
Be knowledgeable of the basic code requirements
There are two main standards for emergency lighting. The Underwriters Laboratories (UL) 924 Standard for Emergency Lighting and Power Equipment dictates how the fixtures should be constructed, and how they should perform. The National Fire Protection Association (NFPA) 101 Life Safety Code dictates how buildings should be illuminated in case of a power outage. There is an important distinction between these two codes: UL 924 describes the fixtures themselves, while NFPA 101 describes how the UL listed fixtures should be installed to provide adequate emergency illumination. Inspectors will check both the fixtures and the installation, but as long as the fixtures are UL 924 listed, most of the inspection problems will arise from the way the fixtures were installed. Thus NFPA 101 is what you should be mindful of.
Although there are numerous local codes in different areas of the U.S., most of those other codes use the NFPA 101 Life Safety Code as their foundation when it comes to laying out the emergency lighting in a project. In general, NFPA 101 defines a "path of egress" that needs to be illuminated even during power outages. Depending on the application, the requirements for emergency illumination vary, but the most widely used rules of thumb in the Life Safety Code are:
90 minutes of emergency illumination after a power outageAn average illumination of one foot-candle at floor level on the path of egressNo less than 0.1 foot-candle at any point in the path of egressA maximum uniformity ratio of 40 to 1 (the brightest spot vs. the darkest spot on the floor).
There are a lot more requirements besides the above four, but knowing those four will allow you to spot possible issues with the project layout so that you can ask the engineers that put the layout together the right questions.
Make sure a qualified engineer has approved the layout
Regulations change from one county to the next, so the codes that apply in one county may not be the same that apply in a neighboring county. Also, different types of buildings have to comply with different regulations. For example, hospitals are required to comply with regulations that are different from residential buildings. The best way to cover all possible angles is to make sure an engineer competent in the codes and regulations that apply to the job site has reviewed and approved the emergency lighting layout.
Be careful when substituting lighting fixtures
Every layout for emergency lighting is created using a specific lighting fixture in mind. If you are substituting the specified fixture with a different one, you need to make sure that the two fixtures are comparable in performance. The most common mistake made in substitutions is to assume that two fixtures are comparable because they use the same type of lamp. In fact, the lamp voltage and wattage are only part of the story when comparing two fixtures. The lens and the reflector of the fixture often make a more significant difference than the lamps. For example, if a designer creates a layout using a fixture with a spot light distribution, but the installer uses a flood type fixture, the illumination levels on the floor will be significantly different from what was originally intended by the designer.
A flood type fixture will give a softer, general illumination with no hot spots. The spot type fixture will give extra punch on the floor when needed, however it could create hot spots that do not meet the uniformity ratios explained above. A good way to identify spot type fixtures is to look at the lamp heads. If the lens is flat and clear and you can clearly see the lamp inside, that fixture is most likely a spot type. If the lens has a texture or a pattern to it and prevents you from seeing the lamp inside, then the fixture is most likely a flood type fixture. In most cases a combination of flood and spot will give the perfect lighting solution.
What to do if the installation still does not pass inspection
In some cases, even after paying attention to all the items explained above, the installer will end up with a layout that still doesn't pass the requirements of the applicable agency codes. In this case, there are a few ways to correct the problem without major re-wiring of the job. The first order of business is to find out what the problem is. Make sure you get a detailed description from the inspector of what is wrong with the installation. Chances are that that inspector will find that there is not enough light on the floor to meet the one foot-candle average illumination. If this is the case, then a couple of options are available to correct the problem:
Find out from the manufacturer of the fixtures if a higher wattage lamp can be installed in the fixtures that were used for the project. Some models of emergency lights have extra battery capacity to allow the user to either install a remote lighting head or to use higher wattage lamps on the fixture heads. If this is possible, then use the highest wattage lamp allowed by the manufacturer. The fixtures have a maximum wattage rating that can't be exceeded, so it is key to stay below that maximum wattage rating. The cost of the higher wattage lamps is usually very affordable, so this is the quickest and least expensive fix.Use remote lighting heads. If the fixture has capacity for higher wattage lamps but these lamps alone are not sufficient to fix the problem, then a remote head may be a better solution. Instead of replacing the lamps, try installing a remote head midway between fixtures. This allows you to "spread" the light and get a better distribution on the floor. Always check to make sure you are not exceeding the maximum watt rating of the fixture. This option will be more expensive than the previous one.If the battery in the fixtures doesn't have any spare capacity, then the only solution is to replace the fixtures. You can choose to go with a fixture with a higher wattage lamp, or a fixture that has light heads with a spot beam pattern. MR16 lamps usually have a stronger punch than wedge base type lamps with a reflector, so a fixture with MR16 lamps could be a good solution.
Daniel Fernandez is Product Management Specialist for Juno Lighting Group, manufacturer of the NaviLite line of exit signs, emergency lighting units, remote heads and accessories. For more information, visit www.junolightinggroup.com
author: By Daniel Fernandez, Juno Lighting Group




Local Articles
Industrial Goods & Services
Home