Powertrain outbreak leads to fluids guide

News |
01.06.2006

New guidance on working with metalworking fluids has been issued by the Health and Safety Executive (HSE) as its latest response to probably the world's biggest occupational asthma outbreak. The outbreak took place at the Powertrain engine plant at the then MG Rover complex at Longbridge in Birmingham. The HSE began its investigation in March 2004, 18 months after the peak of the outbreak, which has so far led to 111 diagnosed cases of occupational asthma and extrinsic allergic alveolitis.

The latest report says the research into the causes of the outbreak "significantly changes the perception of risk of respiratory disease arising from the use of water-mix metalworking and water-based wash fluids."

It says the onset of breathlessness among the workers was consistent with "a widespread, breathable source (or sources) of harmful mist" in the plant and this has been narrowed down to the mist from used metalworking and wash fluids.

Evidence that the cases were traceable to bacterial contamination of the mist, rather than chemical agents in the fluids, includes serological reactions among seven affected workers to bacteria of the type found in the used metalworking fluid in the sump of the coolant system and another test in which one worker reacted strongly to used fluid from the sump but not to unused fluid of the same type used in the coolant system.

The HSE's revised guidance says that risk assessments for metalworking and wash fluids need to cover how harmful bacterial contamination will be monitored and controlled and that, since a safe level of exposure to mist from water-mix metalworking and wash fluids is not known, exposure must be better controlled. "All users of metalworking and wash fluids need to be aware of the risks of serious respiratory disease which may arise from exposure to mist," says the guidance (which is available from www.hse.gov.uk/metalworking/experience/powertrain.pdf).