THERE have been calls for controls on the use of methyl chloride as a refrigerant following the discovery of its use, with deadly consequences, in fake refrigerants.
This highly flammable and toxic refrigerant faced a ban back in the 1920s following a number of deaths but rapidly fell out of use following the introduction of safe CFCs. Now methyl chloride is back and not just as a nasty addition to fake blends - it's openly being marketed as a refrigerant in the Far East, writes Neil Everitt.
And, amazingly, although ozone-depleting, methyl chloride is not included within the restrictions of the Montreal Protocol. So, while the extremely efficient and safe refrigerant R22 is on a phase-out around the world and on the verge of extinction in Europe, methyl chloride faces no such restrictions.
Following revelations that methyl chloride is thought to be implicated in the explosions in refrigerated containers and the deaths of three engineers, Graeme Fox, president of European contractor body AREA has called for action.
'If true, this highlights the fallacy of being too specific when legislating technology,' he told ACR News. 'At the time the Montreal Protocol was drafted, methyl chloride had long since stopped being used as a refrigerant in general practice because of its toxicity and flammability.
'Situations like this can only be avoided, or as near as possible avoided, if dangerous substances are properly regulated across the globe. Safety standards in refrigerant use vary wildly at present when looked at on a global scale. The frightening thing about a situation like this is that the ship could have dangerous flammable toxic gas charged in Vietnam, or wherever, then sails into Europe with an R134a label on it, for example, and the European engineer would be none the wiser. To avoid this it would be better if the basket of Montreal Protocol gases are either expanded to include gases such as methyl chloride, or the specified basket is removed to be replaced by a more generic classification.'
The problem with the reefers has also highlighted the discrepancies within the F-gas regulations. While stationary systems come within the regulations and car air conditioning fall within the MAC laws, refrigeration systems on other 'mobile' vehicles, including vans, trucks and reefers are unregulated.
'This situation highlights one of the deficiencies of the current F-gas regulation that AREA has drawn the Commission's attention to: that of the policing of shipping and transport refrigeration generally between European countries regulated by F-gas and those from out with the EC's control,' said Graeme Fox. 'The Commission have thus far seemed reluctant to expand the current regulation into this field but any evidence of the methyl chloride example would surely force them to take action in this matter.'