This SAE Aerospace Information Report (AIR) covers the design parameters for various methods of humidification applicable to aircraft, the physiological aspects of low humidities, the possible benefits of controlling cabin humidity, the penalties associated with humidification, and the problems which must be solved for practical aircraft humidification systems. The design information is applicable to commercial and military aircraft. The physiological aspects cover all aircraft environmental control applications.

The purpose of this (AIR) is to provide guidelines for the design of aircraft humidification systems. Physiological effects of humidity levels on crew and passengers are reviewed. Various techniques used for cabin humidification are discussed and evaluated. Various potential problems and penalties associated with humidification systems are also described.