This Part of DIN EN ISO 1452 specifies the characteristics of fittings made from unplasticized poly(vinyl chloride) (PVC-U) for piping systems intended for water supply and for buried and above ground drainage and sewerage under pressure. It also specifies the test parameters for the test methods referred to in this standard. In conjunction with Parts 1, 2, and 5 of DIN EN ISO 1452, it is applicable to PVC-U fittings and to joints with components of PVC-U, other plastics and non-plastics materials intended to be used for the following: a) water mains and services buried in ground; b) conveyance of water above ground for both outside and inside buildings; c) buried and above ground drainage and sewerage under pressure. It is applicable to fittings in piping systems intended for the supply of water under pressure up to and including 25 °C (cold water) intended for human consumption and for general purposes as well as for waste water under pressure. This standard is also applicable to components for the conveyance of water and waste water up to and including 45 °C. Depending on the jointing method, this standard is applicable to the following types of fittings: fittings for solvent cementing; elastomeric ring seal fittings. PVC-U fittings can be manufactured by injection-moulding and/or be fabricated from pipe. This document is also applicable to PVC-U flange adapters and to the corresponding flanges made from various materials. This document covers a range of fitting sizes and pressure classes and gives requirements concerning colours.