Which item is a common cause of false alarms?

• A. Drafts or air movement
• B. Full compliance with testing
• C. Proper seal of doors
• D. High-quality wiring

Answer: (A)

Drafts or air movement commonly trigger alarm sensors by creating air disturbances that the system misreads as movement. This is especially true for motion detectors and certain sensitive switches, where a gust of air from a vent, open window, or nearby fan can cause a brief change in readings and set off an alarm. To prevent this, place sensors away from air sources, avoid mounting them where drafts flow directly over them, and adjust sensitivity if needed or use sensor types less prone to air disturbances.

The other options are practices or conditions that typically improve reliability rather than cause false alarms. Ensuring proper door sealing helps prevent drafts from entering the monitored area, high-quality wiring reduces false alarms caused by electrical faults, and following testing procedures correctly improves system accuracy and reduces unnecessary dispatches.