Vietnam has imposed strict controls over the supply of R134a following the contaminated refrigerant scare which caused a number of explosions and three deaths in the refrigerated container industry last year.
It is now known that a total of 1181 units were serviced in Vietnam in 2011 in terminals identified as using contaminated refrigerant. All these units have been isolated and are being tested.
Two units showing chloride contamination which had no connection to Vietnam have recently been found in New Zealand and some contaminated boxes in the United States were found to contain R12/R22 with no trace of methyl chloride (R40).
Details of the contamination and testing were revealed at the Forum on Contaminated Refrigeration Systems, held in Singapore recently.
Organised by the Container Owners Association, the forum focused on the challenges to the container industry caused by the contamination of container refrigeration machinery with counterfeit refrigerant gases.
The forum was attended by representatives from 19 shipping lines, nine leasing companies, 18 container depots together, five inspection companies and four major reefer machinery manufacturers.
Triton Container senior vice president Mark Bennett emphasised the need for co-ordinated action across the industry as the best means of eliminating fake gas supply and identifying clean and contaminated reefer units.
Renze Elzinga of Carrier Transicold presented laboratory work being done by his company on the chemistry of R40 contamination.
Mike Baldwin, president of North American depot network operator ConGlobal Industries, described the flame halide lamp test method for testing cylinders while HRS Rotterdam and RAE Benelux presented an alternative method using gas sniffer tubes.
The RAE sampling kit can identify very low levels of chloride contamination, and it can distinguish between contamination from R12/R22/R124 and that of R40/R142b by different colours.