In an event that power is cut to the location during an emergency or a power outage, emergency and exit lighting is needed. 

The emergency lights switch on, allowing a clear and secure path to the nearest exit.

Every six months, tests are performed to ensure that the batteries are fully charged and that the lights are working and usable under test conditions according to Australian Standard AS2293.2.

How are Exit and Emergency Lights Tested?
Before performing the Emergency and Exit Light checking, Test and Tag will check with management that there will be no disruption to the site.
Inspect all light fittings and diffusers for correct operation prior to testing.
As required, repair any defective tubes or globes.
Isolate emergency lighting from the main power supply for a 90-minute test of battery operation.
Ascertain that all lights meet the requirements and report any defective objects.
When the project is over, re-establish the power supply.
Record each exit and emergency light on the property.