S:-Sustained Mode
An Emergency luminaire containing separate lamps for normal and emergency operation

Definition of Terms
M: Maintained : an emergency luminaire in which the single emergency lamp operates on both normal and emergency mode.

NM: Non-Maintained : an emergency luminaire in which the lamp operates on the emergency mode only, on
failure of the normal supply.

S:Sustained : an emergency luminaire containing separate lamp for normal and emergency mode.

Self-contained : an emergency luminaire with integral batteries, built-in charging system and mains
feature relay/semi-conductor system often incorporating an inverter and controls for
sensing power failure and automatically changing over to emergency batteries power.

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