Abstract: The characteristics of infrared beam smoke detection technology, early aspirated smoke detection technology, and dual discrimination imaging linear beam smoke detection technology were analyzed, and their advantages and disadvantages in application were compared and analyzed. Based on the special requirements for fire detection systems in high space areas of subway projects, three types of smoke fire detection systems were thoroughly demonstrated, and their respective applicability in the area was compared, analyzed, and studied. Taking the design of a dual discrimination imaging linear beam smoke detection system used in a high space area of Ningbo Metro Line 5 Phase I project as an example, combined with on—site measured technical data on sensitivity, interference sources, obstruction sources, and external light source anti—interference, this paper summarizes the advantages of the dual discrimination imaging linear beam smoke detection technology in the application of high space areas in subway projects.

Key words: subway, smoke detection technology, fire detectors, fire alarm