Fire/smoke detecting apparatus installed at ceiling/wall of room, has evaluation device that is provided to evaluate contamination on cover plate based on radiations emitted by radiation emitter and received by radiation receiver

摘要

The apparatus has radiation emitters (14,14') that are partially arranged on an inner side of cover plates (10,10') to emit the radiation in a space. The radiation receivers (16,16') are partially arranged on inner side of cover plate to receive the radiation scattered in space. The fiber optic components (22,22') are arranged for directly passing the radiation emitted from radiation transmitters to the radiation receivers. An evaluation device is provided to evaluate the contamination on cover plate based on radiations emitted by radiation emitter and received by radiation receiver. An independent claim is included for a method for checking operability of fire/smoke detecting apparatus.