This document specifies the characteristics of the fitness for purpose of pipes and/or fittings assemblies made from polyethylene (PE) for buried or above ground applications, intended for the conveyance of water for human consumption, raw water prior to treatment, drainage and sewerage under pressure, vacuum sewer systems, and water for other purposes.
NOTE 1 The intended uses include sea outfalls, laid in water and pipes suspended below bridges.
NOTE 2 This document is intended to be only used by the product manufacturer to assess the performance of components according to ISO 4427‑2 and/or ISO 4427‑3 when joined together under normal and extreme conditions. It is not intended for on-site testing of pipe systems.
This document also specifies the test parameters for the test methods referred to in this document.
In conjunction with the other parts of the ISO 4427 series, this document is applicable to PE pipes, fittings, their joints and to joints with components of PE and other materials, intended to be used under the following conditions:
a) a maximum allowable operating pressure (PFA) up to and including 25 bar[1];
b) an operating temperature of 20 ?C as the reference temperature.
NOTE 3 For other operating temperatures, guidance is given in ISO 4427‑1: 2019, Annex A.
The ISO 4427 series covers a range of maximum allowable operating pressures and gives requirements concerning colours.

[1] 1 bar = 0,1 MPa = 105 Pa; 1 MPa = 1 N/mm2.