The potential for engine oil and hydraulic fluid fumes to contaminate the ventilation air supplied to the aircraft cabin and flight deck has been recognized since the 1950s as a function of the design and maintenance of the bleed air system. The presence of oil and hydraulic fluid in the bleed air matters because the fumes contain complex mixtures of chemicals, including toxic additives. Starting in the 1950s and continuing to this day, crewmembers around the world have documented ill health during and after breathing these fumes. Also, some crewmembers have reported impairment and even incapacitation inflight, resulting in investigations by more than 12 air accident departments. Manufacturers, engineers, and unions have proposed various mitigation strategies including bleed air filtration, real-time sensors to provide early warning of contamination, improved preventive maintenance, and airliner worker training. To-date, though, none of these have been consistently applied. The simplest control measure to implement is training. To that end, the presenter will describe ongoing efforts to ensure that pilots, cabin crew, and maintenance workers are trained to recognize, respond to, and report fume events. The International Civil Aviation Organization, Airlines for America, the American Society of Heating, Refrigeration, and Air Conditioning Engineers, and members of Congress have all proposed programs for airline worker training on fumes. Given the significant crew health and flight safety implications of breathing oil and hydraulic fluid fumes onboard, the importance of crew training cannot be understated
