Which type of heat detector activates automatically when the room temperature increases rapidly?

A rate of rise heat detector is designed to activate when there is a rapid increase in temperature within a space. This type of detector is particularly sensitive to sudden changes in heat, which can be indicative of a fire developing. It monitors the temperature of the environment and triggers an alarm if the temperature rises quickly beyond a preset threshold over a specific period. This feature allows it to respond to fast-moving fires that might not be detected by other types of detectors that require a certain temperature to be reached before activation.

In contrast, a fixed temperature detector requires the temperature to rise to a certain pre-determined level to activate, which makes it less sensitive to quick changes. Smoke detectors, while effective at sensing smoke produced by fires, do not specifically measure temperature changes. Multi-sensor detectors combine various sensing technologies, including smoke and heat detection, but they do not specifically focus on the rapid temperature increase aspect that a rate of rise heat detector does.