Britain’s Marime and Coastguard Agency has issued an MIN regarding the explosion of compressors on refrigerated containers, reefers, some fatal, following the use of contaminated refrigerant during maintenance.
Says the MCA: “It has been brought to our attention that a small number of incidents have recently occurred where the compressor unit on reefer containers has exploded. The reason for the failure of the compressor units is still unclear but it would appear that the system, after servicing, has been recharged or ‘topped up’ using contaminated gas.
“A number of shipping companies are aware of the issue and are quarantining reefer units that they suspect contain contaminated refrigeration systems”.
UK P&I Club has circulated part of an analysis by Cambridge Refrigeration Technology: “Refrigerated Container refrigeration units should contain polyolester oil and the refrigerant HFC-134a (1,1,1,2-Tetrafluoroethane) and should therefore be incapable of exploding.
“Material recovered from the exploded units have been analysed by a laboratory and have found to be corroded by a chlorinated compound. Traces of alumina (AL2O3) were also found at the sites.
“From the above data we can be reasonably certain that the pyrophoric liquid ( burns in contact with air) to be is trimethyl aluminium (Al2(CH3)6). The explanation is that the system has been contaminated with a counterfeit refrigerant containing methyl chloride (chloromethane, CH3Cl). This gas works as a refrigerant but reacts with the aluminium in the compressor forming trimethyl aluminium, which is a liquid at room temperature”.