Description : These type of signs are mostly self lit. They are programmed to self lit in case of a power failure and are essential in all industrial units. The signage unit will include an external rechargeable battery pack and  sometimes a timer and a power sensitive relay. Therefore the unit switches on by itself for a specified time or during a power failure thus guarding precious human lives by guiding to exits.

Advantages : Self operated safety signs

Disadvantages : Periodical maintenance required for smooth functioning.