ISO/TS 15875-7:2003 gives guidance for the assessment of conformity to be included in the manufacturer's quality plan as part of the manufacturer's quality system. It includes: requirements for materials, components, joints and assemblies given in the applicable part(s) of ISO 15875;requirements for the manufacturer's quality system;definitions and procedures to be applied if third-party certification is involved. In conjunction with the other parts of ISO 15875, ISO/TS 15875-7 is applicable to crosslinked polyethylene (PE-X) piping systems intended to be used for hot and cold water installations, within buildings, for the conveyance of water which may or may not be intended for human consumption (domestic systems) or for heating systems, under design pressures and temperatures appropriate to the class of application.