What defines a combined sustained emergency luminaire?

What defines a combined sustained emergency luminaire?

• A. Emergency light containing two lamps, one energized from normal lighting supply other from emergency lighting supply and it is designed to Sustain lights at all times
• B. Only emergency power, no normal supply
• C. Light that turns off during emergency
• D. Light with battery only

Answer: (A)

A combined sustained emergency luminaire is a single fixture designed to operate from both the normal mains supply and an emergency power source, providing continuous illumination even if the mains fail. It achieves this with two lamps: one powered from the normal lighting circuit and a second powered from the emergency supply, so the light can stay on at all times. The “sustained” aspect means it is maintained—on during normal operation and automatically continuing to light during an outage. This is why the description fits best: two lamps, one on the normal supply and one on the emergency supply, built to sustain light continuously. Other options describe lights that either rely only on emergency power, turn off during an emergency, or run on battery alone, which do not provide the same maintained dual-function.

A combined sustained emergency luminaire is a single fixture designed to operate from both the normal mains supply and an emergency power source, providing continuous illumination even if the mains fail. It achieves this with two lamps: one powered from the normal lighting circuit and a second powered from the emergency supply, so the light can stay on at all times. The “sustained” aspect means it is maintained—on during normal operation and automatically continuing to light during an outage. This is why the description fits best: two lamps, one on the normal supply and one on the emergency supply, built to sustain light continuously. Other options describe lights that either rely only on emergency power, turn off during an emergency, or run on battery alone, which do not provide the same maintained dual-function.