Glow in the dark is a star safety signs material

Remember those glow in the dark stars on your bedroom ceiling? After a trip to any museum or almost anywhere with a gift shop, it's what I'd want to take home with me. The same principle that kept you gazing at the ceiling all night – is what makes photoluminescent safety signs so great.

Using ambient UV light to store energy, photoluminescent materials give back or emit that energy in the form of visible light. They're doing this all the time, without batteries or any form of power source.

If you specify your safety signs as 'photoluminescent' this means that in the event of an emergency, if power is lost, or in smoke filled conditions people can more easily:

• Find the exit routes from the building
• Find the fire alarm call button
• Find the refuge point if you have one
• Be aware of floor trip hazards or head height restrictions
• Find the fire extinguishers if they need to fight the fire
• Find any other safety equipment required

Photoluminescent safety signs work 24hrs a day 365 days a year with little or no maintenance. The only thing you might need to do is wipe them clean if you're operating in a particularly messy environment.

In order to ensure that safety signs made with photoluminescent materials meet a minimum performance level there are some standards covering the materials which can be used. These standards define the brightness of the initial 'glow' and for how long the signs will stay visible once the ambient light source is removed. The brightness of the 'glow' is defined in mcd/m2 and it's allowed decay (reduction over time) in minutes.

The absolute minimum standard is PSPA Class A (Photoluminescent Safety Products Association) which when tested according to DIN67510 pt 1 is defined as 108mcd/m2 after 2 minutes, down to 3mcd/m2 after 60 minutes and down to 0.32mcd/m2 (the minimum to still be visible) after more than 450 minutes. Most safety sign manufacturers will use a material meeting a minimum of PSPA class B, but the highest performing materials, for example for use in marine environments, could use class D. ISO 23601 (Safety Identification - Escape Plan Signs) actually specifies a PSPA class C material as being the minimum required performance level.

Whilst the primary use for photoluminescent materials is of course for glow in the dark stars – it's also great for way finding, escape route marking, egress systems, emergency and safety signage.

The primary safety sign uses are:

• Fire Exit Signs
• Fire Extinguisher instructions for use
• Fire Action Signs
• Fire door keep shut signs
• Fire alarm call point signs
• Fire Equipment Signage
• Push bar to open signs

To make it easy for the end user many safety sign suppliers also offer a choice of either rigid photoluminescent safety signs or a cheaper alternative using a self adhesive vinyl – both with the same added safety benefits that their 'glow in the dark' attributes bring.