This Standard addresses the discipline of environmental control and life support (ECLS) and the interfaces to other disciplines of engineering and to the domains of management and product assurance. It also introduces the structure and applicability of the associated Level 3 Standards. The environmental control and life support systems (ECLSS) covered in this Standard includes those aspects relating to the assurance of a safe and comfortable environment for human beings undertaking a space mission. When other forms of life are accommodated on board, the ECLSS also ensures the appropriate environmental conditions for those living organisms. This Standard applies to all ECLSS for: all manned space endeavours and manrated space products, and any other form of life to be maintained on board. This standard may be tailored for the specific characteristics and constrains of a space project in conformance with ECSS-S-ST-00.