Indoor Air Quality in Commercial Air Transportation

This chapter deals with the air quality in means of air transportation. Since air travel in large passenger aircraft represents the vast majority of travel, the air quality in commercial aircraft cabins is vitally important to the public.At typical cruising altitudes between 31,000 and 41,000 ft (about 9,500 and 12,500 m), ambient conditions of very low temperature and pressure, elevated ozone concentrations, and dry air constitute a hostile environment to human beings. To create a life-supporting atmosphere inside the aircraft, environmental control systems provide appropriate regulation of pressure, temperature, and ventilation in the cabin. As aircraft cabins increasingly become part of the normal habitat for humans, passenger and crew expectations for the cabin environment are rising, leading to additional requirements for environmental control systems.Air pollution sources in aircraft cabins can be attributed to passengers and their personal hygiene, activities in the cabin, carry-on luggage, cabin equipment and materials, outside air contaminants, and very rarely, to abnormal conditions or pollution of system components like compressors, ducting, or fans in the air supply path.Many volatile organic compounds (VOCs) found in aircraft cabins do not differ from compounds found in residential buildings and offices, and concentrations are in the same range or even lower. Some semivolatile organic compounds (SVOCs) from, e.g., flame-retardants or operational fluids are more specific for the aircraft environment but only occur in trace concentrations. Environmental ozone can be reliably reduced in high-temperature sections of the air supply system and by employing converters. Average carbon dioxide concentrations are higher than in other environments but are kept well below regulatory limits for aircraft cabins.