Military Fire Extinguisher Signs, 2 Count

Photoluminescence DHi's® AfterGlow® brand military fire extinguisher signs use strontium aluminate (SrAl), a much newer “Safety Grade” photoluminescent (PL), or "glow in the dark", phosphor that is non-toxic and non-radioactive, and retains its ability to be recharged and glow brightly for many, many years. Typically, the luminance life span is 30+ years for safety-grade strontium aluminate (SrAl) materials and only 3-4 years for novelty-grade zinc sulfide (ZnS) materials. A full charge of 8 or more hours of luminance of DHi's AfterGlow® photoluminescent military fire extinguisher sign is achieved by exposing the PL material to:

• 3-4 minutes of ultraviolet (black) light, or
• 7-8 minutes of direct sunlight, or
• 21-23 minutes of fluorescent light, or
• 24-26 minutes of incandescent light.

Retroreflectivity Most materials absorb light or scatter it in random directions, where retroreflective materials reflect light directly back to the light source by passing light through spherical glass optical elements onto a mirror, or by using cube corner reflectors, in order to optimize reflection and create a high visibility surface. Today’s prismatic retroreflective sheeting can return as much as 60% of the light to the viewer. Retroreflective materials are often used by emergency personnel like police officers, paramedics, and firefighters to make them more visible in dark or low light situations. These materials are also commonly used for path marking or to improve safety where traffic control is important, and visibility of normal signs may be difficult.