Emergency lighting is essential for providing illumination when an emergency situation arises or the power goes out. It helps evacuate people to safety and can prevent panic, confusion, and injury in a building or area. There are two types of emergency lighting: self-contained units and central systems. Self-contained units are independent fixtures that contain their own batteries and light sources, while central systems are wired into the facility’s electrical system but have backup generators in case of power failure. Both types provide illumination during an evacuation, however they differ in terms of installation time, cost efficiency, maintenance requirements and other factors. Ultimately it comes down to understanding your needs as well as the layout of your building before selecting which type of emergency lighting system is best for you.