THE co-pilot of a British passenger jet had to be put on oxygen in mid-flight after being overcome by a suspected leak of engine fumes into the cockpit, safety records have revealed.

Researchers are working on a new product designed to help directly assess the constituent parts of the aircraft cabin environment while analysing incidents involving fumes.

It forms part of on-going efforts to study whether a link exists between short- and long-term illnesses recorded by cockpit and cabin crew and, as some believe, their exposure to contaminated air supply in the cabin as a result of incidents of oil leakage from the engine or auxiliary power unit.

The British Air Line Pilots Association (BALPA) has already joined forces with the UK's Imperial College and University College London to submit a research paper on the subject to the UK Aviation Health Working Group.

It also sponsored a recent conference in London which aimed to raise the profile of the issue further. The Contaminated Air Protection conference brought together medical and scientific experts to discuss the issue.

Speaking at the conference, former Australian senator John Woodley - who chaired a critical Australian Senate report into air safety and cabin air quality on the BAe 146 - bemoaned the lack of will from regulators to further investigate the issue. That Senate report, published in 2000, called on the Australian Civil Aviation Safety Authority (CASA) to reassess its earlier rejection of reports identifying fumes-related health and safety concerns.

"I believe the regulators have been asleep. I believe they should stop mucking around and start playing the game seriously," said Woodley.

Another campaigner for more research into the issue, the retiring UK Parliamentary member and long-standing chair of the All Party Organophosphate Parliamentary Group, Paul Tyler, also hit out at regulators for failing to deal with the issue.

"Unless the Civil Aviation Authority and its international equivalents take a determined initiative to get to the bottom of this problem, the fear will remain that air contamination will one day cause a major disaster - complacency and buck-passing to those who have a commercial interest in minimising the threat is no longer acceptable," he says.

Most attention on the issue has centred on previous cabin-fume incidents involving the BAe 146, where oil leakages from the APU or engine contaminated the cabin or cockpit air supply. While concerns have been raised, aviation regulators remain to be convinced evidence exists to confirm a direct link between contaminated air occurrences and illnesses reported by cabin and cockpit crew.

For example the UK CAA which, between 2001-03, conducted generic research into possible contaminants that could arise in aircraft air conditioning systems, concluded no component or set of components could be identified which - at conceivable concentrations - would definitely cause the symptoms reported in cabin air quality incidents.

It did, though, identify the presence of short chain organic acids that could cause irritants, the effects of which vary greatly between individuals.

University of British Colombia professor of health care and epidemiology Chris van Netten says: "We are not looking at one component but we are looking at many components acting together in one space."

He says the key to establishing whether a link exists rests in improving the understanding of the conditions of exposure in such incidents. "You have to look at what the exposure is and what are the conditions of the exposure," he says.

Van Netten notes information on this can be obtained through a variety of indirect methods. For example, he says he has discovered tri-cresyl phosphate contaminants in cabin air conditioning recirculation filters and, earlier this month, on a pilot's trousers, which he says indicates the substance's presence in the cabin air at some point during such incidents.

However he acknowledges that direct assessment of the constituents of the cabin air taken during such fume incidents is preferable. Direct measurements from such cases have not so far been recorded. But to combat the obstacle of crew's having to carry and operate complicated equipment on board numerous flights in case of an incident, he has developed an easy-to-use basic sampler.

"You can [record] a whole fingerprint of the air quality during one of these incidents," he says, noting work is now underway on the logistics of manufacturing the product on a larger scale.

Following the conference another UK union, the Transport and General Workers Union (T&G), called on the UK Health and Safety Executive to require all UK-registered aircraft to have bleed air filtration systems fitted on all aircraft used for passenger transport above a maximum take-off weight of 5,700kg to ensure crew and passengers are protected from contaminated air.

T&G regional industrial organiser Oliver Richardson, who is responsible for the body's cabin crew members, suggests: "The cost to put these filters on aircraft is a small price to pay to protect the travelling public."

It also wants it made mandatory for airlines to inform passengers when they have been exposed to contaminated air.

Source: Air Transport Intelligence news