Air in the dual sensing chambers is irradiated to produce ions that travel to the positive and negative electrodes, creating a current flow. As smoke enters the outer chamber, the flow drops and the voltage increases. The detector will then enter the alarm state and the indicator LED lights up.

Air in the dual sensing chambers is irradiated to produce ions that travel to the positive and negative electrodes, creating a current flow. As smoke enters the outer chamber, the flow drops and the voltage increases. The detector will then enter the alarm state and the indicator LED lights up.