What types of fire detectors are commonly used on ships?

The most commonly used types of fire detectors on ships include ionization and photoelectric detectors, as they are specifically designed to identify the presence of smoke or combustion products efficiently. Ionization detectors utilize radioactive material to detect fast-moving particles produced by flames. They are highly sensitive to flaming fires but less so to smoldering fires. On the other hand, photoelectric detectors use a light beam and a light sensor; they are particularly effective at detecting larger particles from smoldering fires.

While thermal and smoke detectors (often combined) are essential as they respond to temperature changes and smoke respectively, ionization and photoelectric technologies provide a dual approach that enhances overall fire detection capabilities on board. Manual and automatic detectors serve different purposes, with manual requiring human intervention and automatic triggering alarms based on detected fire signs.

Although UV (ultraviolet) detectors can detect flames at a fast rate and infrared (IV) detectors can recognize hot surfaces, a combination of these may not be as widely implemented due to sensitivity to false alarms from other sources and higher costs. Thus, the preferred option is the combination of ionization and photoelectric systems, which is often regarded as best practice in fire detection on maritime vessels.