In unsprinklered hoistways, what is the permitted use of smoke detectors?

In unsprinklered hoistways, what is the permitted use of smoke detectors?

• A. Activate smoke relief equipment
• B. Trigger alarm only
• C. Zap power to hoist motor
• D. Open hoistway doors

Answer: (A)

In unsprinklered hoistways, smoke detectors are used to drive the shaft ventilation system. When smoke is detected, the detectors activate smoke relief equipment—like hoistway dampers and fans—to vent the smoke out of the shaft. This helps keep the hoistway safer, improves visibility for occupants and responders, and reduces heat buildup. Triggering an alarm without venting the shaft doesn’t address the smoke in the hoistway. Cutting power to the hoist motor or opening hoistway doors aren’t the intended or safe responses from smoke detectors in this scenario, and they could create dangerous conditions. Venting the hoistway smoke is the primary, appropriate action.

In unsprinklered hoistways, smoke detectors are used to drive the shaft ventilation system. When smoke is detected, the detectors activate smoke relief equipment—like hoistway dampers and fans—to vent the smoke out of the shaft. This helps keep the hoistway safer, improves visibility for occupants and responders, and reduces heat buildup.

Triggering an alarm without venting the shaft doesn’t address the smoke in the hoistway. Cutting power to the hoist motor or opening hoistway doors aren’t the intended or safe responses from smoke detectors in this scenario, and they could create dangerous conditions. Venting the hoistway smoke is the primary, appropriate action.