BS 7291-3:2010

This part of BS 7291 specifies general requirements and methods of test for cross-linked polyethylene (PE-X) pipe and fitting systems intended for use within buildings for the conveyance of cold water, including drinking water, and heated water for use in domestic hot and cold water distribution and heating installations. These requirements supplement the general requirements in BS 7291‑1 which are also applicable

NOTE 1 Before reading this part, it is essential to read BS 7291‑1.

NOTE 2 Methods of test are given in Annex A and Annex B. Annex C gives guidance on factory control procedures.

This British Standard specifies general requirements for materials to be used for or in the form of PE-X pipes, with or without a barrier layer or associated fittings and components. Particular requirements are also specified for PE-X pipe alone or jointed with push-fit and compression fittings conforming to BS 7291 or other British Standards intended for use with pipes conforming to this part.

This part of BS 7291 provides for pipes dimensioned to suit two established metric series: BS ISO 4065 for thermoplastics pipes generally and BS EN 1057 for compatibility with copper pipework systems widely used for these applications.

This British Standard is applicable only to Class “S” pipes and fittings.

It does not specify dimensional requirements for fittings because the performance requirements specified for fittings, when tested individually or in assemblies with pipe, are intended to ensure that the dimensions of the fittings are satisfactory for jointing purposes and pressure containment.

NOTE 3 Pipes and fittings of non-barrier PE-X are to some extent permeable to oxygen; hence, if they are used for the primary circuit(s) of a heating system, it might be beneficial to add a corrosion inhibitor to the fluids circulating therein. In such a case the manufacturer(s) of the pipe and/or fitting should, upon request, provide advice in accordance with BS 5955‑8. This advice should include selection of a compatible corrosion inhibitor and/or methods for reducing the permeability.