Since the 1950s, crew members have documented ill health – esp. neurological deficits – after breathing oil fumes that contain a mixture of organophosphate additives, including tricresyl phosphates (TCPs). Industry and military teams investigated reported symptoms, patterns of exposure, chemical constituents of the fumes, and control measures. The industry response was, initially, swift. Boeing researched bleed air filtration options and applied for a patent for bleed-free air supply design in 1954. North American Aviation did a two-year investigation into reports of flight deck fumes and recommended bleed-free ventilation or bleed air filtration. But industry response shifted from finding solutions to rationalizing reality. More rationalizations claimed that chemical exposure limits assure safety. It was argued that for the TCPs in oils, only the ortho isomers were toxic, and they will not comprise more than 0.2% of TCP blend added to oils, so the 'toxic content' would be too low to be a problem. Even the EASA-funded Cabin Air Quality report from 2017 shows outdated thinking and bias against validity of crew reports: "A human exposure study is the long-needed tool to provide an unequivocal and sound dataset to end the misguided discussion on cabin air quality once and for all." In 2023 crews continue to report fume events, ill health, flight safety issues. Very little has been achieved in 60 years. Still only one aircraft type with bleed-free air supply system design exists (B787). No bleed air filters for cabin air are available (only one option for B757 flight deck). No sensors exist to alert crews of oil fumes. There is limited training for crews to recognize/respond to fume events. There is still no standardized fume event reporting system. The new research project is titled "Cabin air quality assessment of long-term effects of contaminants". Crews support this, but after the project is one year in and unions have not been invited to consult or been asked for feedback. What opportunities will there be for labor to get more involved and provide feedback? Crew challenge the work packages of the ongoing research of "CAQ3". Crew demand exposure control measures: 1.) bleed free designs, 2.) less toxic oils and hydraulic fluids, 3.) effective bleed air filtration / air cleaning technology, 4.) real-time detection systems, 5.) mandatory crew education and training, 6.) standardized fume event reporting systems, 7.) disease recognition. Previous EASA-sponsored research was CAQ1, CAQ2, and FACTS. All have collected information. Crew asked: How does the new project FACTS2 = QAQ3 build on what earlier projects have found? Why is the focus still on repeating data collection instead of defining exposure control measures?

EASA Cabin Air Quality Research Workshop, Cologne, Germany, 17-18 January 2023