Air Quality Systems for Related Enclosed Spaces: Spacecraft Air

Abstract

Air quality in the small, closed environment of a spacecraft cabin is always a critical matter for the safety, health, and comfort of the crew. The technologies used to keep air breathable in spacecraft have a unique set of requirements because of several constraints that become more important as the duration and distance of space missions lengthen. Technologies must be extremely robust, as supplies and spare parts are few and resupply may be impossible. They must be well coordinated and function in a tightly integrated life-support system. Mass, volume, and power consumption must be minimal due to the high cost of launch mass and limited solar/battery energy. This article examines some of the issues associated with spacecraft air revitalization and briefly reviews some of the technologies developed to maintain quality and minimize waste through recycling of air. We emphasize approaches for long-duration missions (i.e., more than one month), in which technologies need to be regenerable and the oxygen cycle needs to approach closure. We also discuss air revitalization systems for the International Space Station and needs for long-distance missions such as Mars transit.