With the current hubbub over the costs of environmental legislation, one of the cheaper and more effective ways of going green for new building construction, or renovations of existing buildings, is in the exit signs. They can even save you significant amounts of money!
Regulations in place since the dawn of the last century require all buildings with an intended occupancy of more than 10 people to have self illuminating exit signs. These have to be bright enough to be visible in an emergency and through smoke or fire suppression systems, and that requires a certain level of lumens. They also have to be ‘on’ 24/7, with battery backup systems.
Factored together, this results in an ongoing expense for building owners that can mount up pretty quickly – with a typical exit light needing about 10 watts of power (for a fluorescent one), that’s 3.6 kilowatt hours, times 365 days a year, times the number of exit lights you have to run – much like leaving computer equipment on constantly, this is a daily tally that adds up significantly over time.
When combined with the effort and expense of checking to make sure the battery system in the light works, replacement of batteries when those die, and similar, it’s no wonder more and more businesses and builders are moving towards self illuminating exit signs; for decades, these were dominated by tritium gas bulbs, but disposal issues have made those less appealing as an option, while advances in photoluminescent materials have made these the primary option for self illuminating exit signs.
Photoluminescent materials need to be exposed to light to activate – if you’ve ever had one of those glow-in-the-dark toys that needed to be set out in daylight to be activated, you’ve seen photoluminescence in action. Since the mid 1990s, advances in materials science have made this category of material brighter, more forgiving in how much light it needs to activate, and tied it to reflective bases to make it appear much brighter; these materials are now rated as being safe by most of the nationwide and statewide building codes, and are significantly cheaper to install and maintain. These signs are now at the point where they can pay for themselves in reduced electricity expenses within a year or two of their installation in most cases.