This document specifies the general aspects of polyethylene (PE) compounds for the manufacture of pressure pipes and fittings (mains and service pipes) 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;
— water for other purposes.
This document also specifies the test parameters and requirements for the test methods referred to in this document.
In conjunction with other parts of the ISO 4427 series, this document is applicable to PE pipes and fittings, their joints and to joints with components made 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 1 For other operating temperatures, guidance is given in Annex A.
The ISO 4427 series covers a range of maximum allowable operating pressures and gives requirements concerning colours.
NOTE 2 It is the responsibility of the purchaser or specifier to make the appropriate selections from these aspects, taking into account their particular requirements and installation practices or codes.

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