International travel and health


Ozone is a form of oxygen that occurs in the upper atmosphere and may enter the aircraft cabin together with the fresh-air supply. In older aircraft, it was found that the levels of ozone in cabin air could sometimes lead to irritation of the lungs, eyes and nasal tissues. Ozone is broken down by heat and a significant amount of ozone is removed by the engine compressors (which compress and heat the air) that provide pressurized air for the cabin. In addition, most modern long-haul jet aircraft are fitted with equipment (catalytic converters) that breaks down any remaining ozone.