Patent ID: 8705038
Filing Date: 2014-04-22
Classification: G01N

Abstract:
1. A particle detection unit comprising: a duct detector, for disposal within a duct, including a rod having a first and a second end, the first end distal the second end, a reflector attached to the rod adjacent the first end, a sensor/emitter device attached to the rod and spaced apart from the reflector at a second end, wherein the sensor/emitter device is configured to detect particles disposed between the first and second ends; wherein the duct detector is operatively connected to a central control panel located remote from the duct detector, the central control panel configured to initiate a remote self-test of the duct detector; and wherein the self-test of the duct detector comprises decreasing the sensor/emitter's light output by a predetermined amount to simulate the light reduction caused by a predetermined amount of smoke.