3.1 This specification relates to detectors, both
portable and permanently installed, capable of detecting interfaces
of liquids having a wide range of density differences. A detector,
however, may be tested for one or several specified applications,
e.g. interface between oils as defined in Annex I of the 1973 MARPOL
Convention and salt water, brackish water or fresh water. The approval
document should clearly state the accepted applications and any relevant
limitations.
3.2 The detector and its associated depth measuring
equipment should be practical, reliable and constructed of materials
suitable for use in the marine environment.
3.3 It should comply with the relevant statutory
requirements for use in hazardous areas on oil tankers and should
not interfere with radiocommunication.
3.4 The accuracy of the detector indication should
be such that it will indicate within ± 25 mm the actual position
of a sharply defined interface between oil and water.
3.5 The detector should respond promptly and in
a distinctive manner to changes between oil and water.
3.6 The instrument should be capable of being
checked on board for correct working.