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Photoluminescent Egress and Exit signs are powerless alternative to standard "Hard-Wired" Exit Signs. Learn about the principles of Photoluminescence and if they are the correct Exit Signage choice for you.
General Concepts of Photoluminescence
Photoluminescent signs are so named because they are illuminated via the action of photoluminescence. Energy in the form of light (photons) is absorbed from their surroundings by the special coating and stored. This stored energy is then re-emitted as light, making the light "glow" when the building is dark.
What is 54 lux?
54 lux is the minimum level of lighting that is legally required to "charge" a photoluminescent sign. Lux being the ambiant light level. As a comparison, the average office in the United States measures an ambiant light level of 50 lux.
How do you turn on photoluminescent signs?
You do not have to do anything to activate a photoluminescent sign except to make sure that it gets sufficient light energy to stay "charged". Your photoluminescent sign is always on once it has absorbed a sufficient amount of energy. Take it into a dark room and turn off the lights to view the illumination.
Are photoluminescent signs bright enough?
Yes, photoluminescent signs meet or exceed Underwriters Laboratories (UL) minimum requirement for emergency egress signage.
Are photoluminescent signs safe?
Yes, photoluminescent signs are non-toxic, non-radioactive, and require no special handling.
Are photoluminescent signs approved?
Yes, photoluminescent signs meet the requirements of the NFPA®, Life Safety Code 101®, the International Building Code®, and the International Fire Code®. Other approvals/acceptances include: Underwriters Laboratories Inc. (UL), Occupational Safety and Health Administration (OSHA0, the American Society for Standards and Materials (ASTM E), and the New York City Building Code.
Are photoluminescent signs reliable?
Yes, photoluminescent signs have been around for decades, and have a proven track record. Also, photoluminescent signs have no moving parts and as long as they are "charged" via light source they are 100% reliable for their 25+ year lifespan.
Do photoluminescent signs require maintenance?
With no moving parts, and no consumables, photoluminescent signs are virtually maintenance free. They should be inspected regularly, and signs should be kept free of dirt and debris with simple cleaning with soap and water.
How do photoluminescent signs save money?
Photoluminescent signs require almost no maintenance, require no power (no electricity), and can be easily (and inexpensively) installed almost anywhere.
How long does it take to "charge" a photoluminescent sign?
UL 924 requires that the photoluminescent sign face be exposed for 60 minutes to 54 lux of fluorescent, metal halide, or mercury light to fully "charge" the sign. Brighter light intensity (lux) produces shorter charging time.
How long do photoluminescent signs glow?
After full "charging", it takes about 16 - 96 hours in total darkness for a photoluminescent sign to fully discharge.
Is there radiation from photoluminescent signs?
No, photoluminescent signs are non-radioactive, and emit light through the mechanism of photoluminescence.
How long do photoluminescent signs last?
Under normal conditions, your photoluminescent sign should last for 25+ years.
What do I do with my outdated photoluminescent signs?
There are no special steps or handling required to dispose of photoluminescent signs.