Emergency lights come in many forms and are used to illuminate an area during an emergency or when power goes out in a building.
The main forms of emergency lighting are typically those powered by the backup generator of a building, batteries, and even solar power.
This type is often used for a safety light, a standby one, and to illuminate escape routes.
  Backup Generator Lights   Many buildings have a backup generator installed that supplies emergency power.
This is often provided by a diesel engine or an engine that is powered by natural gas.
Emergency lights are wired to switch on if the generator is activated.
They are often used to power low-level lighting that allows people inside of a building to find their way out safely.
  Batteries and Solar Power   Some types of emergency lights are designed to run off of batteries.
When power does out, the batteries in these lights are used to provide temporary power.
You can also find other types that will run on solar power.
These lights also use a battery, but the battery is being charged by the sun.
Batteries for a solar light are kept constantly charged.
A flashlight is an example of a LED emergency one requiring a battery.
  Safety Lights   This type of lighting is also known as high-risk task lighting.
These ones are used to illuminate places or areas in a building that need to be accessed in an emergency.
This includes the access to stairwells or hallways that would otherwise be dark if the power went out.
Manufacturing plants often have this type of lighting to allow workers to quickly exit a building or to shut down equipment.
  Standby Lights   These lights are installed in buildings that have a backup generator.
When a power failure occurs, these are used to allow critical work to continue.
They are often found in hospitals, fire stations, and in other buildings that require continually running services.
Standby lights will activate and power on if a power failure occurs or the main power goes out.
  Escape Route Lighting   Hallways and paths that are used to evacuate a building will require escape lighting.
These will often be LED emergency light that are floor mounted.
When power goes out, these lights are used to provide a lighted path to an outside door or exit out of a building.
The use of escape lighting is designed to keep a person from getting disoriented.
A common area for escape lighting is a movie theatre.
  Additional Information   A common type of emergency light is an exit sign that is located over the door for a building.
This light is often powered by a battery.