Glow in the Dark Signs: Why Are They Necessary for Egress Safety?
Building safety signs come in a variety of styles and applications. But all building safety signs can be separated into one of two categories: glow in the dark signs and signs that don’t glow in the dark. Often referred to as luminescent signs, most glow in the dark signs for building safety are illumined by principle of photoluminescence, which occurs when an object absorbs photons from its surroundings and then re-radiates them, creating a discernible glowing effect. In nature, photoluminescence is generally a brief process, lasting only a few seconds. But photoluminescent emergency exit signs and other signage are engineered to glow for up to 96 hours in total darkness.
Photoluminescence as a safety technology began in the late 1980’s and early 1990’s with the relative popularization of photoluminescent exit signs. But, unlike the photoluminescent safety products of today, early photoluminescent signs didn’t glow very brightly or for very long. Today, however, luminescent signage has emerged to become the most recommended signage for building safety. Unlike building safety signs of the past, which often have a reflective surface that proves useless in presence of accumulating smoke, today’s photoluminescent building signs provide superior visibility at 100 feet under smoky conditions, making them essential for large commercial and R1 residential buildings that contain occupancy on high floors.
For building owners who wish to implement luminescent safety signs, consulting the 2009 version of the International Fire Code (IFC) is the best option. Created by the International Code Council (ICC) to regulate egress safety in commercial and residential R1 buildings that contain occupancy at above 75 feet from the lowest level of fire department vehicle access, the IFC establishes the importance of luminescent safety signs by requiring that emergency exit symbols be placed on all exit-leading doors within vertical exit enclosures and exit passageways, and that floor identification signs be mounted at every floor landing within vertical exit enclosures.