This International Standard specifies requirements for lightweight polytetrafluoroethylene (PTFE) hose assemblies for use in aircraft hydraulic systems at temperatures between − 55 °C and 204 °C (− 65 °F and 400 °F), and at a nominal pressure up to 3 000 psi (20 684 kPa) or 21 000 kPa (3 046 psi). The hose assemblies are also suitable for use within the same temperature and pressure limitations in aircraft pneumatic systems where some gaseous diffusion through the wall on the PTFE liner may be tolerated. The use of these hose assemblies in high-pressure pneumatic storage systems is not recommended. In addition, installations in which the limits specified in this International Standard are exceeded, or in which the application is not covered specifically by this International Standard, for example for oxygen, are subject to the approval of the purchaser. Annex A is a listing of hose assembly procurement standards conforming to this International Standard.