ISO 14531-3:2010 specifies the physical properties and mechanical-performance requirements for full-end-load-resistant mechanical fittings for use in the connection of crosslinked polyethylene (PEX) pipes conforming to ISO 145311 and in the construction of transition assemblies for joining PEX pipes to metal pipes having plain spigot, screw thread, compression socket and flange terminations. In addition, it lays down dimensional requirements and specifies some general material properties (including chemical resistance) together with a classification scheme for PEX fitting materials produced in the form of pipe.
ISO 14531-3:2010, when used in conjunction with the other parts of ISO 14531, provides the basis for the design, manufacture and installation of PEX piping systems (PEX pipes, PEX fusion fittings and mechanical fittings) for the supply of category D and category E hydrocarbon-based fuels.