What stage of fire can an ionization detector best detect?

An ionization detector is particularly adept at detecting the incipient stage of a fire. This is the earliest phase of fire development, where the flames have not yet fully developed but there is an increase in smoke particles due to combustion. Ionization detectors are designed to respond to the small, fast-moving particles produced by flaming fires, making them very effective early warning devices when a fire is just beginning.

During the incipient stage, the fire is generating smoke and gases, which the ionization detector can sense through changes in the ionization current within its chamber. This ability allows for timely alarms that can prompt immediate action, potentially preventing the fire from reaching more dangerous stages. In contrast, fully developed or extinguishment stages produce different conditions that may not be as effectively detected by ionization sensors.