With the technological advances of today's Army aircraft and the increase of operational requirements to conduct operations at altitudes exceeding 10,000 feet MSL, oxygen equipment and cabin pressurization are crucial. Without supplemental oxygen and cabin pressurization, crew members increase their risks of hypoxia, evolved-gas disorders, and decompression sickness. This chapter explains cabin pressurization and oxygen equipment and their use in Army aviation. The oxygen systems can exist in many forms throughout the military, but the following equipment is used in Army aircraft. Aviator's gaseous oxygen is the most common breathing oxygen found in Army aircraft.
Gaseous oxygen is odorless and free from contaminants.
The oxygen used for medical purposes is classified as Type I, Grade B, and is not acceptable for use by aviators because of its high moisture content. This is important because at high altitudes the temperature may cause freezing in the oxygen-delivery system and restrict the flow of oxygen. The use of this system reduces many of the potential hazards associated with gaseous high-pressure systems. In addition, the service and maintenance of this system is simpler than other systems. Various onboard oxygen-generating systems have been tested, and some show great potential for future military use.