Light-storing pigments form the base of photoluminescent materials. Photoluminescent materials contain pigments that are charged by a light source, preferably cool white light. The pigments absorb the light and emit it over an extended period of time.
The bright initial photoluminescent effect decreases gradually over the time. Nevertheless, it remains visible to the human eye as this adapts to the darkness. Therefore, photoluminescent markings will help escaping people find their way even after a few hours - in total darkness as well as in heavy smoke. Tests of photoluminescent emergency evacuation systems have shown that test participants were able to escape without major limitations even after hours in the dark.
The three major factors for the grade of luminance of the pigments are:
· the light intensity at the place of application, measured in Lux or footcandles
· the kind of illumination / color temperature, measured in Kelvin
· time of charging, measured in minutes.
The pigments can be reactivated continuously under the condition that there is no mechanical or chemical damage on the product.
Currently, the most common used pigment is strontium aluminate. It is non-toxic, not radioactive, and free of lead and phosphor and has a low flammability. So it is absolutely harmless to your health and provides a high level of safety.
If you want to test the photoluminescent effect, following there is a simple method:
Take the photoluminescent samples into a room and space them a few inches apart from each other. Activate them for approximately 30 minutes with light; fluorescent light would be the best activation source. After that turn off all lights and observe the darkness effect for at least 10 minutes. Once you turn off the light, you will immediately see the bright photoluminescent effect. Initially, the room will appear pitch black, but as your eyes adapt to the darkness over the time, room features will become visible to your eyes. Exit the room then, leaving the photoluminescent samples in the dark. If you return after an about an hour and do not turn on the lights, you will notice your light-adapted eyes quickly adjusting to the surrounding darkness – and the photoluminescent material will appear ‘out of the dark’ again.
In addition to this easy test, you can ask us for luminance certificates. Luminance certificates give exact information on the duration of the photoluminescent properties of your product.
Exit Systems provides a multitude of options for photoluminescent markings and signage. We equip your building with high quality materials. To see our catalog, please click here!
