Cabin Environment
There is an erroneous perception that the cabin environment of a pressurized aircraft 1 is bad. That is not true. Treated by
HEPA (High Efficiency Particulate Arrestance) filters – similar to those used in organ transplanting and burn hospital units – the air
in airplane cabins is climatized and dehydrated, which makes the environment free from fungi and bacteria and - because the air
relative humidity becomes very low – even protects the existing airborne electronic equipment (avionics). The air flow is directed
[5] downwards, thus reducing the rate of contamination between seats. Additionally, all of the cabin air is replaced every three minutes.
This will keep the oxygen rates throughout the aircraft at much higher levels than those required by human consumption, and
carbon dioxide and particulate matter at acceptable levels with respect to passenger safety, health and comfort.
(Adaptado de: TAM magazine, ano 3, nº 34, dez. 2006.)
Consider the following sentences:
1. It is generally believed that the air that passengers breathe inside an airplane cabin is unhealthy.
2. Low humidity contributes to free the air from fungi and bacteria.
3. The treatment of the air inside a pressurized cabin helps to maintain avionics.
4. The levels of oxygen rates inside the aircraft tend to be unbearable when passengers leave the airplane.
According to the text:
