Frequently Asked Questions

How do the materials work?

 

JALITE photoluminescent materials contain purpose designed inorganic phosphor compounds that are energised in seconds by the ultra violet and blue light wavelength energy that is present in nearly all light sources.

 

The energising mechanism is through the excitation of electrons within the phosphor crystal which jump into a higher energy band or orbit. They are "trapped" as they try to return to their normal orbit in electron traps caused by specific impurites in the crystal structure.These trapped electrons will escape from the trap slowly through the action of vibrations due to temperature. As they escape and lose the excited energy, they release the characteristic light.

JALITE materials have been especially chosen to give the number and depth of the electron traps to provide the optimum balance of high brightness and great longevity. 

 

The characteristic lower energy light source is yellow-green, this colour is the most readily perceived by the human eye and is as now specified by safety signs standards.

 

JALITE photoluminescent materials are non-radioactive and non-toxic and provide a strong light source. They are also self-extinguishing, so they carry on working when they are most needed.




How long does it last?

The most frequently asked of all the frequently asked questions!

 

How long is a piece of string? How long do you want it to last?

 

This question firstly needs us to define the end point - at what luminance is the material still useful for egress or for effective visual communications.

 

The most common end point used in the industry is the time to reach a luminance of 0.3 mcd/m2 or 100 times the threshold perception level of the human eye.

 

Recently industry experts have accepted that a more "useful" time would be the time to reach 3 mcd/m2 - 1000 times the perception threshold and a luminance that has been accepted as offering useful guidance information.

 

Whatever the end point chosen, the determining factors are the type of material, the amount of light and type of light available for activation.

 

Whatever rubbish is given by others with claims of 10, 20, 30 hours ! be assured that JALITE answer to this question is simple - How long do you want?



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