Very Often , People, even in familiar buildings, may become frightened & disorientated during an emergency. The occupants’ reaction times, speed of adaptation, chance of panicking & ability to walk in a straight line may be different (e.g. users have disabilities or have taken alcohol or drugs).

It is also designed for High-Risk Task Area which usually are hazardous area or workplaces involving risk assessment It is also designed for High-Risk Task Area which usually are hazardous area or workplaces involving risk assessment will identify any hazardous work processes and locations needing special consideration. A proper shut-down procedures are needed for the safety of operations and all the other occupants of the premises. For example in places such as plant or production lines where machines are running , in laboratories handling hazardous , control rooms that such as plant or production lines where machines are running , in laboratories handling hazardous , control rooms that manage dangerous processes.

For EN1838:2013 details that the maintained illuminance on the reference plane shall not be less than 10% of the required maintained illuminance for that task and never less than 15 lux. This may require emergency luminaire to be operated in maintained mode for high-risk task area.