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Carbon dioxide levels, relative humidity, and temperature and flight factors in commercial aircraft cabins.

Waters M; Deddens J
American Industrial Hygiene Conference and Exposition, May 20-25, 2000, Orlando, Florida. Fairfax, VA: American Industrial Hygiene Association, 2000 May; :28-29
For the NIOSH/FAA Working Women's Health Study, exposures to cabin environmental contaminants were measured on 33 commercial aircraft flights. One objective of the exposure assessment was to characterize carbon dioxide (CO2) exposure distributions, temperature, and relative humidity (RH) and their relationship to flight factors such as aircraft size, occupancy, ventilation, and flight length. Flights ranged in duration from 33 to 851 minutes on 10 types of aircraft. Continuous measurements were made at two locations in the coach cabin from gate departure to gate arrival using direct-reading data-logging instruments. Gate-to-gate mean concentrations of CO2 ranged from 859 ppm to 2379 ppm. Five-minute time-weighted averages (TWAs) ranged from 664 ppm to 4904 ppm CO2 and were highest during boarding and deplaning. Variations in gate-to-gate mean CO2 levels between forward and rear locations on the same flight ranged from 0.5% to 27%. CO2 levels were highest on shorter flights, flights with high occupancy ratios, aircraft with air recirculation, and narrow-bodied aircraft. These levels largely do not meet the ASHRAE 62-1989 criteria of <1000 ppm CO2 for indoor environments; however, they are within the FAA Federal Aviation Regulation limit for commercial aircraft cabins of <30,000 ppm CO2. Relative humidity gate-to-gate mean levels ranged from 10.1% to 45.6% and 5-minute TWAs ranged from 5.4% to 61.9%. RH levels were lowest on long-duration flights with low occupancy ratios, wide-bodied aircraft, aircraft with no air recirculation, and aircraft operating at higher altitudes. Temperature gate-to-gate mean levels ranged from 22.4 degrees C to 28.2 degrees C, with 5-minute TWAs ranging from 19 degrees C to 29.5 degrees C. Variations in gate-to-gate mean temperatures between forward and rear locations on the same flight ranged from 0 degrees C to 3.2 degrees C, and simultaneous 5-minute TWA temperatures varied even more between locations. These conditions do not generally meet ANSI/ASHRAE Standard 55-1992 thermal comfort criteria for buildings. However, humidification of this environment is costly and might pose other cabin environmental problems.
Flight-personnel; Aircrews; Aircraft; Air-contamination; Women; Work-environment; Environmental-contamination; Indoor-air-pollution; Indoor-environmental-quality; Exposure-assessment; Dioxides; Relative-humidity; Temperature-measurement; Ventilation; Air-quality-measurement; Air-sampling; Time-weighted-average-exposure; Exposure-levels; Permissible-concentration-limits; Regulations; Altitude; Standards
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American Industrial Hygiene Conference and Exposition, May 20-25, 2000, Orlando, Florida
Page last reviewed: May 11, 2023
Content source: National Institute for Occupational Safety and Health Education and Information Division