THE New Zealand Department of Labour has recommended that coldstore owners and operators immediately determine what refrigerant their refrigeration systems are charged with after an engineer suffered burns while carrying out maintenance on an R22 coolstore evaporator that actually contained hydrocarbon refrigerant.

A hazard alert was posted on the Department of Labour website after officials found 'disturbing' parallels with the fatal Tamahere Icepak coolstore explosion in 2008, in which one fireman was killed and seven injured. The officers were unaware that the system contained hydrocarbons.

In this latest incident in May, the technician, who received burns to his face and hands, was contracted to repair a valve, clearly marked as R22, on the coolstore evaporator.

The system was pumped down, isolating the bulk of the refrigerant to the main plant situated outside the building. Welding around the valve area is said to have ignited the residual refrigerant inside the system, causing a rapidly expanding fire ball to erupt into the technician's face. He slid down the access ladder to avoid further injury as the fireball rose to the coolstore's ceiling.

The incident is said to have caused significant damage to the refrigeration plant and equipment.