PROBLEM TO BE SOLVED: To obtain a fire detector which minimizes the adhesion of material being the cause of strains to a light receiving window in which a detecting sensor is housed to make a cleaning work interval long while maintaining a fire monitoring function being the same as in the conventional practice and also can efficiently perform cleaning work and its arranging method about a fire detector to be installed in a tunnel. ;SOLUTION: In this fire detector 10 detecting a fire taking place in a tunnel, a wind protecting part 13 provided in a sensor housing part 12 is oriented on the upstream side of an air stream C caused by the traveling, etc., of vehicles passing through the tunnel, and meanwhile, an inclining part 14 and a light receiving window 15 provided in the part 12 are oriented on the downstream side of the stream C. Consequently, the window 15 is located at a hidden side that is prevented by being blown upon directly by the stream C all the time.;COPYRIGHT: (C)2000,JPO
展开▼