Battery Backup
Products with battery backup contain a battery so in the case of a power outage the lights or signs with stay illuminated for roughly 90 minutes.
Tritium
Tritium lumination is the use of gaseous
tritium, a radioactive
isotope of
hydrogen, to create visible light. Tritium emits
electrons through
beta decay, and, when they interact with a phosphor material,
fluorescent light is created, a process called
radioluminescence. As tritium illumination requires no electrical energy, it found wide use in applications such as emergency
exit signs and illumination of wristwatches. More recently, many applications using
radioactive materials have been replaced with
photoluminescent materials.
