Patent ID: 6611207
Filing Date: 2003-08-26
Classification: G08B

Abstract:
A method of detecting fire by smoke-emission analysis, comprising the steps of:training across a monitored area to be protected against fire from one side a plurality of discrete infrared beams capable of being intercepted by smoke particles emitted upon development of a fire condition; detecting the discrete infrared beams on another side of the monitored area and generating video signals in response to detecting, the generated video signals representing attenuation of the discrete infrared beams by smoke particles; processing the video signals to determine at least a possibility of a fire condition in the monitored area; enabling an alarm in response to determining the fire condition if: upon comparing each of the processed video signals to an alarm threshold, the processed video signal exceeds the alarm threshold, upon sequentially comparing each of the processed video signals to the alarm threshold and a turning threshold, a respective processed video signal exceeds the turning threshold, or upon determining that all of the processed video signals exceed the turning threshold.