Cabin Air Pollutants and Climate in an Aircraft with Recirculated Air on Intercontinental Flights

Measurements of air humidity, temperature, carbon dioxide (CO2), respirable particles, ozone, nitrogen dioxide (NO2), formaldehyde, and volatile organic compounds of possible microbial origin (MVOC) were performed during 26 flights with Boeing 767-300. The mean temperature in cabin was 22.2 °C (range 17.4-26.8 °C), and mean relative air humidity was 6% (range 1-27%). The CO2 during cruises was below 1,000 ppm during 96 % of measured time. Mean concentration of NO2 and ozone O3, were 14.1 μg/m3 and 19.2 μg/m3, with maximum values of 37 μg/m and 66 μg/m, respectively. Formaldehyde was below the detection limit (<5 μg/m), in most samples (77%) (Maximum value was 15 μg/m). The mean concentration of respirable particles in the rear part of the cabin was much higher during smoking (mean 49 μg/m: maximum 253 μg/m3) than non-smoking (mean 3 μg/m) (p<0.001). Different MVOC were detected, including 3-methyl-1-butanol, 1-octen-3-ol, at higher levels than in Swedish dwellings. INDEX TERMS Cabin air quality, Carbon dioxide (CO2), Environmental tobacco smoke, Microbial VOC, Relative air humidity INTRODUCTION Aircraft nowadays transports more than 1,000 million people annually (Owe, 1997). Because of increased fuel cost, recirculated is often used in the cabin (Hocking, 2000). In a larger questionnaire study, complaints about cabin environment were found to be more common in aircrew than office workers (Lindgren et al., 2000). In another study on cabin crew, Lee et al (2000) found frequent complaints on the cabin environment, particularly on unpleasant odour and low air humidity. Environmental factors considered in previous studies have included low relative air humidity (5-25%) (Lee et al., 1999; de Ree et al, 2000; Backman et al, 2000), carbon dioxide concentration (CO2) (Haghighat et al., 1999; Lee et al., 1999), particulate pollutants in relation to smoking onboard (e.g. Lee et al., 1999; Dechow et al.; 1997), and chemical pollutants such as ozone (O3) (Reed et al., 1980; Tashkin et al., 1983), formaldehyde, and nitrogen dioxide (NO2) (Pierce et al., 1999; O'Donnell et al., 1991). The main aim was to perform continuous measurements of cabin temperature, air humidity, CO2, and respirable particles in the working areas of an aircraft (Boeing 767) commonly used in intercontinental flights. The second aim was to measure NO2, O3, formaldehyde, and volatile organic compounds of possible microbial origin (MVOC) in cabin air. We also * Contact author email: [email protected] Proceedings: Indoor Air 2002