What is considered a self luminous exit sign?
Any sign that doesn’t require external electrical power to be illuminated is considered “self-luminous.” A sign using Tritium gas would be the best example, another example would be a photoluminescent sign. However there is some controversy as to whether such a sign is truly “self-luminous” since photoluminescent technology requires some external source of illumination for it to luminesce. This external source is, in most cases, electrically powered, so while the sign requires no direct application of power it does rely on the indirect use of electricity.
