Fire Detection Using Reflected Near Infrared Radiation and Source TemperatureDiscrimination

摘要

A new type of near infrared (NIR) fire detector which utlizes a statisticalanalysis of apparent source temperatures of fire was developed. The NIR fire detector measures the spectral radiation intensities emanating from fires at 900 and 1000 nm. These measurements are used to obtain and a time series of apparent source temperatures. The near infrared radiation characteristics of five standard test fires specified in the guidelines of the European Committee for Standardization were measured and utilized to develop a fire detection algorithm. The five test fires specified in the guidelines involved a heptane pool, a polyurethane foam, a wooden crib, a smoldering cotton and a smoldering wood. The NIR fire detector was evaluated for sensitivity to both direct and reflected radiation from the five test fires. When direct radiation is incident on the NIR fire detector, four of the five test fires were always detected. The smoldering wood fire was detected only if the NIR fire detector was very close. The NIR fire detector can also detect the heptane pool, the polyurethane foam and the wooden crib fires from reflected radiation. The response time of the NIR fire detector ranged from approximately 1 to 4 minutes for the open fires. The NIR fire detector had no instances of false alarms during the test period.