This International Standard specifies safety and performance requirements for anaesthetic systems that: a) can function in the absence of a supply of compressed medical gases or mains electricity; b) can withstand a challenging environment, including high temperatures, humidity, shocks and vibration, and dust; c) allow local servicing and maintenance; d) may be suitable for use with flammable anaesthetic agents. This International Standard allows the construction of an anaesthetic system using the components identified in this International Standard to suit the specific economical and environmental issues of each country.