What type of detectors includes fixed temperature and rate of rise detectors?

Heat detectors are designed to respond to the presence of heat. Fixed temperature detectors activate when the ambient temperature rises to a predetermined level, signaling potential fire conditions. On the other hand, rate of rise detectors monitor changes in temperature; they trigger an alarm when the temperature increases rapidly over a short period. Both types are critical in fire safety systems because they can provide early warning in situations where smoke may not be present, such as in certain industrial environments or in areas where smoke detectors might produce false alarms.

Smoke detectors, although effective in many situations, rely on the presence of smoke particles to detect fires. Flame detectors are designed to respond to the actual flames or intense heat from a fire and would not include fixed temperature or rate of rise functionalities. Carbon monoxide detectors measure the presence of carbon monoxide gas and have different operational parameters altogether. Therefore, the characteristics of heat detectors make them the appropriate choice in the context provided.