PASS alarms are designed to activate when:

• A. A firefighter is motionless for more than 30 seconds
• B. Firefighters encounter hazardous materials at an incident scene
• C. Toxic gases have been detected in the surrounding atmosphere
• D. The amount of air in the SCBA cylinder drops below 50% capacity

Answer: (A)

PASS alarms are designed to alert others when a firefighter becomes motionless and may be in distress. The device waits a short period—about 30 seconds—without detecting movement, then sounds and flashes to signal that the wearer needs assistance. This function is specifically about locating and rescuing a downed or incapacitated firefighter, not about detecting hazards, toxic gases, or monitoring air supply. Hazardous materials or gas detectors handle those dangers, and the SCBA’s low-air warning covers air quantity, not a motion-based distress signal. So the correct idea is that the alarm activates when a firefighter stops moving for a set time, indicating a potential emergency.