Project Title: Ozone in Passenger Cabins

passenger-cabinAnticipated Outcome: The scientific data from this research will enable the FAA and the aerospace industry to ensure that airworthiness (FAR 25.832) and operational (FAR 121.578) regulations for ozone are appropriate and that the actual levels of ozone in commercial airliners during flight remain within limits that are safe and healthy.

Project Summary: Ozone is an important pollutant in the aircraft cabin environment. Originating in the stratosphere and produced by natural chemical processes, ozone can be introduced into airliner cabins by the aircraft ventilation system during flight. The FAA has established both airworthiness (FAR 25.832) and operational (FAR 121.578) regulations to limit ozone in passenger cabins.

ACER members University of California – Berkeley and University of Medicine and Dentistry of New Jersey are developing scientific, technological and empirical information needed to understand ozone as an air pollutant in aircraft cabins. The research is organized into four tasks: (1) In-flight monitoring of ozone; (2) Ozone reactive chemistry relevant to the cabin environment; (3) Human exposures and reactive chemistry in a simulated cabin environment; and (4) In-flight monitoring of the byproducts of ozone-initiated chemistry. Recent research measurements have shown that the FAR 25.832 ozone limits were exceeded during 4 of 75 domestic flights during 2006-2007.

Additional research at UCB and UMDNJ has shown that passengers and crew can also be exposed to volatile carbonyls, dicarbonyls and hydroxyl carbonyls that originate from ozone reactions within the cabin. Some of these compounds are known respiratory irritants and, while the toxicological effects of the levels present in aircraft have not been determined, increases in general adverse symptoms were found in simulated flights even at very low levels. It appears that ozone limits might actually be achieved on some flight segments by the reaction of ozone with relatively benign compounds — producing potentially harmful air contaminants!

Research Team:
Bill Nazaroff, University of California – Berkeley
Beverly Coleman, University of California – Berkeley
Charlie Weschler, University of Medicine and Dentistry of New Jersey

Collaborator:
Ray Wells, NIOSH

Recent Scientific Papers and Technical Reports:
“Ozone consumption and volatile byproduct formation from surface reactions with aircraft cabin materials and clothing fabrics,” Beverly Coleman, Hugo Destaillats, Alfred Hodgson, William Nazaroff, Atmospheric Environment, Vol. 42 (4), February 2008, pp. 642-654.

“Ozone levels in passenger cabins of commercial aircraft on North American and transoceanic routes,” Seema Bhangarm Shannon Cowlin, Brett Singer, Richard Sextro, William Nazaroff, Environmental Science and Technology, Vol. 42, No. 11, June 2008, pp 3938-3943.

“The influence of ozone on passenger symptoms in a simulated aircraft cabin,” Peter StrØm-Tejsen, Charles J Weschler, Pawel Wargocki, Danuta MyskÓw, Julita Zarzycka, Journal Exposure Science & Environ. Epidemiology, Vol. 18, 2008, p. 272.

“Ozone-initiated chemistry in an occupied simulated aircraft cabin,” Charles J. Weschler, Armin Wisthaler, Shannon Cowlin, Gyöngyi Tamás, Peter Strøm-Tejsen, Alfred Hodgson, Hugo Destaillats, Jason Herrington, Junfeng Zhang, William Nazaroff,Environmental Science and Technology, Vol. 41, No. 17, September 2007, pp. 6177-6184.

“Factors affecting ozone removal rates in a simulated aircraft cabin environment,” Gyöngyi Tamás, Charles J. Werschler, Zsolt Bakó-Biró, David P. Wyon, Peter Strøm-Tejsen, Atmospheric Environment, Vol. 40, No. 32., 2006, p. 6122.