ISO 10502:2012 specifies requirements for polytetrafluoroethylene (PTFE) hose assemblies for use in aircraft hydraulic, fuel and lubricating oil systems at temperatures between -55°C (-67°F) and 232°C (450°F) for Class I assemblies and between -55°C (-67°F) and 135°C (275°F) for Class II assemblies, and at nominal pressures up to 10 500 kPa (1 523 psi) (105 bar). The hose assemblies are also suitable for use within the same temperature and pressure limitations in aerospace pneumatic systems where some gaseous diffusion through the wall of the PTFE liner is tolerated.ISO 10502:2012 covers hose assemblies of the following classes:? class I: hose assemblies with fitting of corrosion-resistant steel or titanium parts [232°C (450°F)];? class II: hose assemblies with fitting of corrosion-resistant steel and aluminium parts [135°C (275 ?F)], DN12 and larger.