What is the maximum distance between the highest switch, lamp, or textual display and the finished floor?

• A. 8 ft (2.4 m)
• B. 6 ft (1.8 m)
• C. 4 ft (1.2 m)
• D. 10 ft (3.0 m)

Answer: (B)

The main idea is accessibility and visibility of controls and indicators. To make sure people can reach and read or operate switches, lamps, or textual displays during normal use or an alarm, these devices are kept within a reachable height. The maximum allowed distance from the finished floor to the top of such a device is six feet. That height balances being high enough to be out of reach of everyday obstacles on the floor, while still low enough for most people—including someone standing or in a wheelchair—to reach and read or operate.

Choosing a height higher than six feet would put these devices out of easy reach for many occupants, complicating evacuation or status checks. A height of four feet would be lower than typical placement needs in many spaces, making devices more prone to obstruction or accidental operation. Heights like eight or ten feet are simply impractical for quick access.