UNE-EN ISO 15875-3:2026

This document specifies the characteristics of fittings for crosslinked polyethylene (PE-X) piping systems intended to be used for hot and cold water installations within buildings for the conveyance of water,

whether or not intended for human consumption (domestic systems) and for heating systems under design pressures and temperatures according to the class of application (see ISO 15875-1).

It also specifies the test parameters for the test methods referred to in this standard.

The designation crosslinked polyethylene is used together with the abbreviation PE-X throughout ISO 15875, including this document.

ISO 15875 covers a range of service conditions (application classes) and design pressure classes. For values of design temperature (TD), maximum temperature (Tmax) and malfunction temperature (Tmal) and service

times in excess of those defined in ISO 15875-1, this document does not apply.

NOTE 1 It is the responsibility of the purchaser or specifier to make the appropriate selections from these application classes (see ISO 15875 part 1), taking into account their particular requirements and any relevant national

regulations and installation practices or codes.

The ISO 15875 standards series is a piping system standard.

This document shall only be used in conjunction with all the other parts of ISO 15875. This document is applicable to fittings made from PE-X or other plastics or non-plastics materials, which are intended to

be connected to pipes conforming to ISO 15875-2 for hot and cold water installations, whereby the joints conform to the requirements of ISO 15875-5.

In order to comply with this standard all requirements of this document have to be met.

NOTE 2 The test results obtained from a specific piping system test according ISO 15875 part 5 cannot be transferred to other combinations of pipes and fittings.

This document is applicable to fittings of the following types:

mechanical fittings;

electrofusion fittings;