The OSI-RE-SS is often a reflector- sort linear optical beam smoke detector designed to run as a part of fire alarm devices. The beam operates primarily on the basic principle of sunshine obscuration utilising an Infra-Crimson beam. OSI-R-SS can be a 4-wire conventional reflector-variety linear optical beam smoke detector to https://www.firesense.co.uk/type/conventional-fire-system/conventional-beam-detectors/