DETECT-A-FIRE® (D-A-F) detectors are the "heart" of many fire protection systems. The highly reliable D-A-F has been the standard for over 75 years. The D-A-F is used for signaling overheat or fire conditions. In the vast majority of applications, the D-A-F provides the initial heat sensing that is used to activate suppression systems using clean agent, CO2, inert gases, wet or dry chemicals or water. D-A-F detectors are widely accepted, because they are designed with rate compensation. This provides a unique advantage over both fixed temperature and rate-of-rise types of detectors because the D-A-F detector accurately senses the surrounding air temperature regardless of the fire growth rate. At the pre-determined set point, the system is activated.