NASCLA Accredited Commercial General ContractorSpecialties and EquipmentMedium

A general contractor is installing an automatic revolving door system at the main entrance of a commercial building. Which of the following safety features is mandated by building codes and industry standards to prevent entrapment and ensure pedestrian safety?

  1. APresence sensors and emergency stop buttons.
  2. BManual override for continuous rotation during peak hours.
  3. CIntegrated intercom system for emergency communication.
  4. DTinted glass for glare reduction.
Show answer & explanation

Correct answer: A. Presence sensors and emergency stop buttons.

Presence sensors detect pedestrians and stop or slow the door to prevent entrapment, while emergency stop buttons provide a direct means for occupants to halt the door in a hazardous situation, both of which are critical safety features for automatic revolving doors.

Why the other options are wrong

  • B. Continuous rotation override would increase, not decrease, entrapment risk.
  • C. An intercom system is for communication, not direct entrapment prevention.
  • D. Tinted glass is an aesthetic and comfort feature, not a primary safety mechanism against entrapment.

Revolving Door Safety

Safety features integrated into automatic revolving doors to prevent pedestrian injury, particularly entrapment, and ensure safe operation.

  • Mandated by building codes and ANSI/BHMA standards.
  • Includes sensors to detect presence and prevent crushing.
  • Emergency stop buttons allow immediate manual halt of operation.

Memory trick: Automatic doors must 'Sense' you and have a 'Stop' button.

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