When a defect detector alarms, you should hear what as the train passes?

When a defect detector alarms, you should hear what as the train passes?

• A. An alarm sounds
• B. A green light appears
• C. A whistle sounds
• D. No notification occurs

Answer: (A)

Defect detectors are placed along the track to catch problems as a train passes. When one detects an out-of-spec condition, it triggers an audible alarm so the crew is immediately warned and can respond—usually by slowing down or stopping to check the issue. That audible alarm is the immediate cue the crew relies on. A green light would typically indicate normal status, not an alarm; a whistle is the locomotive horn, not the detector’s alert; and no notification would defeat the safety purpose of the system.

Defect detectors are placed along the track to catch problems as a train passes. When one detects an out-of-spec condition, it triggers an audible alarm so the crew is immediately warned and can respond—usually by slowing down or stopping to check the issue. That audible alarm is the immediate cue the crew relies on. A green light would typically indicate normal status, not an alarm; a whistle is the locomotive horn, not the detector’s alert; and no notification would defeat the safety purpose of the system.