How many fire detectors are installed on each engine?

• A. 2
• B. 3
• C. 4
• D. 5

Answer: (B)

Fire detection in engine spaces relies on monitoring multiple zones around each engine so a fire is detected quickly. Having three detectors per engine gives reliable coverage of the most heat-prone areas—the engine block area, the exhaust/charger region, and the surrounding space near the installation. This spread ensures that if a fire starts in one spot, at least one detector will sense it promptly, enabling fast alarms and response. With only two detectors, there’s a greater risk of a blind spot where a fire could develop unnoticed. Adding more than three per engine tends to be unnecessary, adds cost, and can lead to nuisance alarms without meaningfully improving protection. So, three detectors per engine strikes a practical balance between thorough monitoring and sensible wiring and maintenance.