ISO 21969:2009 applies to high-pressure flexible connections intended to be connected to cylinders or cylinder bundles with nominal filling pressures up to 25 000 kPa at 15 °C for use with the following medical gases: oxygen; nitrous oxide; air for breathing; helium; carbon dioxide; xenon; mixtures of the gases listed above; air for driving surgical tools; nitrogen for driving surgical tools; oxygen-enriched air. ISO 21969:2009 applies to high-pressure flexible connections intended to connect cylinders or cylinder bundles to manifolds within sources of supply of medical gas pipeline systems complying with ISO 7396-1. ISO 21969:2009 applies to high-pressure flexible connections intended to connect a cylinder to an inlet port of medical equipment (e.g. anaesthetic workstation or lung ventilator) fitted with an integral pressure regulator complying with ISO 10524-1.