What is the minimum average illumination required by emergency lighting at floor level for all types of egress components?

What is the minimum average illumination required by emergency lighting at floor level for all types of egress components?

• A. One foot-candle
• B. Ten foot-candles
• C. Five foot-candles
• D. Zero point five foot-candles

Answer: (A)

The key idea here is the minimum average light level provided by emergency lighting on the floor along every means of egress. In an emergency, normal power may be out, so emergency lighting must give occupants enough visibility to move toward an exit. The standard requires at least one foot-candle of illumination on the floor, averaged along the entire egress path. This floor-level measurement ensures you’re actually seeing the space where you walk, not just the walls or ceiling, and the average ensures gaps in some sections don’t drop the overall level below the minimum. Higher levels aren’t required as the minimum, but anything above that would still be acceptable; a level like 0.5 foot-candles would be too dim to reliably see obstacles or steps.

The key idea here is the minimum average light level provided by emergency lighting on the floor along every means of egress. In an emergency, normal power may be out, so emergency lighting must give occupants enough visibility to move toward an exit. The standard requires at least one foot-candle of illumination on the floor, averaged along the entire egress path. This floor-level measurement ensures you’re actually seeing the space where you walk, not just the walls or ceiling, and the average ensures gaps in some sections don’t drop the overall level below the minimum. Higher levels aren’t required as the minimum, but anything above that would still be acceptable; a level like 0.5 foot-candles would be too dim to reliably see obstacles or steps.