The Orbis Marine Heat Detector range incorporates six heat detector classes to suit a wide variety of operating conditions in which smoke detectors are unsuitable.

The European Standard EN 54-5 classifies heat detectors to the highest ambient temperature in which they can safely be used without risk of false alarm. The classes are identified by the letters A to G (Class 1 is sub-divided into A1 and A2). In addition to the basic classification, detectors may be identified by a suffix to show that they are rate-of-rise (suffix R) or fixed (static) temperature (suffix S) types.

All heat detectors in the Orbis Marine range are tested as static or rate-of-rise detectors and are classified as A1R, A2S, BR, BS, CR and CS.