The heat detector that activates when heated to the temperature for which they are rated, least prone to false activations but can be slow to activate, is called?

The heat detector that activates when heated to the temperature for which they are rated, least prone to false activations but can be slow to activate, is called?

• A. Rate-of-Rise Detector
• B. Fixed-Temperature Detector
• C. Photoelectric Detector
• D. Ionization Detector

Answer: (B)

Heat detectors used in fire alarm systems come in two common types: fixed-temperature and rate-of-rise. The fixed-temperature detector is designed to alarm when the surrounding area reaches a specific, rated temperature. Because it waits for heat to reach that preset level, it is less likely to trigger from minor temperature fluctuations or transient heat sources, giving it fewer false activations. The trade-off is slower response time in a real fire, since the heat must accumulate to the threshold before it alarms. In contrast, a rate-of-rise detector looks for a rapid temperature increase and can activate quickly, but it may be more prone to nuisance alarms from drafts or non-fire heat spikes. Photoelectric and ionization detectors are smoke detectors, not heat detectors, so they don’t fit the description of a heat detector.

Heat detectors used in fire alarm systems come in two common types: fixed-temperature and rate-of-rise. The fixed-temperature detector is designed to alarm when the surrounding area reaches a specific, rated temperature. Because it waits for heat to reach that preset level, it is less likely to trigger from minor temperature fluctuations or transient heat sources, giving it fewer false activations. The trade-off is slower response time in a real fire, since the heat must accumulate to the threshold before it alarms. In contrast, a rate-of-rise detector looks for a rapid temperature increase and can activate quickly, but it may be more prone to nuisance alarms from drafts or non-fire heat spikes. Photoelectric and ionization detectors are smoke detectors, not heat detectors, so they don’t fit the description of a heat detector.