An Austrian-led team of scientists say further improvements are needed before new technology can be used to upgrade air quality in commercial aircraft.
Armin Wisthaler and colleagues at the University of Innsbruck studied photocatalytic oxidation, a leading candidate for improving air quality in commercial jetliners.
Existing air purification technology removes airborne particles, but not odors or the volatile organic compounds that might cause eye and nose irritation. Photocatalytic oxidation units can remove VOCs, and aircraft manufacturers have considered using that technology in combination with existing air filtration systems.
The researchers checked the ability of two prototype air cleaners, combining filtration and photocatalytic oxidation, during simulated seven-hour flights. A seemingly trivial event — the opening of alcohol-moistened wet wipes distributed with airline meals for hand cleaning — alerted the researchers to an unanticipated problem with the photocatalytic technology.
Photocatalytic oxidation changed airborne alcohol emitted from the wipes into unacceptably high levels of acetaldehyde, a colorless volatile substance. Alcohol also can filter into cabin air from other hygienic products, such as alcoholic beverages, cosmetics and medicines.
The study is detailed in the Jan. 1 issue of the journal Environmental Science & Technology.
