1.1 This International Standard specifies requirements, test methods and performance criteria for resettable oil mist detectors for use in fire hazard alarm systems installed on marine vessels. Oil mist detectors may be installed where an identified risk of fire caused by ignition of flammable liquids, such as hydraulic, fuel and lubricating oil systems, exists. 1.2 This International Standard specifies requirements for the following detectors: — point type detectors employing a point aspirating sampling device or relying on dispersion of oil mist; — aspirating detectors, whereby the sampling point is separated from the sensing unit(s) and uses a pipe network for carrying the sampling air to the sensing unit(s); — open path or beam type detectors, whereby the concept of the point detector is expanded to a sampling path which can be 20 m or more, as opposed to a few centimetres in the point type detector. 1.3 For the testing of other types of detector working on different principles, this International Standard is only for guidance. Detectors with special characteristics and developed for specific risks, as well as those designed for use in explosive atmospheres, are not covered by this International Standard.