Put simply, photoluminescence (often referred to as P.L.) is the emission of light from any form of matter after excitation from another light source. Time periods between the absorption and emission can vary greatly from milliseconds to minutes. Similarly, the degree of luminance and its longevity can vary depending on the level of excitation achieved.
The real beauty of photoluminescent products, in the context of a Safety Way Guidance System, is that they do not need electricity to glow in the dark if properly sited and maintained. In an emergency situation where a mains failure has occurred, they will immediately light the way to safety even in smoke conditions.
A photoluminescent fire exit safety sign will look like this is daylight conditions.
But turn off the lights
and it looks like this.
When designing a non-electrical photoluminescent safety way guidance system (Non – Electrical SWGS) you will need to study all the relevant Standards for photoluminescent products and the application. ISO 16069 2017 has been updated for that purpose and gives many design guidance parameters. The decision to install a Non Electrical SWGS has normally been taken as a result of a systematic fire and disaster risk assessment. ISO 16069 gives basic design parameters for users to choose the quality of material as specified in ISO 17398 and amount of material to be used to produce effective egress in corridors and stairs for example. All Non Electrical SWGS should have comprehensive low location and well installed escape route signing. These products are described by Standards such as ISO 7010 and also as in ISO 16069.
All PSPA members can be contacted and should be able to offer all end users a useful basis for design of such systems.