MSC 85/26/Add.2 ANNEX 3 RESOLUTION MSC.268(85) - US Coast ...

MSC 85/26/Add.2ANNEX 3Page 133.4 log the results on a form which records cargo space, date and time for eachmeasurement; and.5 put back the sealing cap.2.4 Measurement strategyThe identification of incipient self-heating from measurement of gas concentrations is morereadily achieved under unventilated conditions. This is not always desirable because of thepossibility of the accumulation of methane to dangerous concentrations. This is primarily, butnot exclusively, a problem in the early stages of a voyage. Therefore it is recommended thatcargo spaces are initially ventilated until measured methane concentrations are at an acceptablylow level.2.5 Measurement in unventilated holdsUnder normal conditions one measurement per day is sufficient as a precautionary measure.However, if carbon monoxide levels are higher than 30 ppm then the frequency shall beincreased to at least twice a day at suitably spaced intervals. Any additional results shall belogged.2.6 Measurement in ventilated holds2.6.1 If the presence of methane is such that the ventilators are required to remain open, then adifferent procedure shall be applied to enable the onset of any incipient self-heating to bedetected.2.6.2 To obtain meaningful data the ventilators shall be closed for a period before themeasurements are taken. This period may be chosen to suit the operational requirements of thevessel, but it is recommended that it is not less than four hours. It is vital in the interests of datainterpretation that the shutdown time is constant whichever time period is selected. Thesemeasurements shall be taken on a daily basis.2.7 Measurement in cargo and self-unloading spaces of gravity fed self-unloading bulkcarrier2.7.1 Measurement in unventilated cargo and self-unloading spaces2.7.1.1 When the shipper has declared that the coal cargo has or may have self-heatingcharacteristics, the holds shall not be ventilated unless otherwise specified in this section.2.7.1.2 Under normal conditions one measurement per day is sufficient as a precautionarymeasure. If carbon monoxide levels are higher than 30 ppm then the frequency of measurementsshall be increased to at least twice daily, at suitable intervals. Any additional results shall belogged.I:\MSC\85\26-Add-2.doc