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WIS 4-02-03 Issue 2 Operational Requirements: In Situ Polymeric Lining of Service Pipes

These Operational Requirements cover material selection, pipeline cleaning, material application, curing, inspection and return to service requirements needed to provide protective coatings for service pipes constructed of galvanised iron, steel, lead, copper and malleable black iron, or as otherwise limited by the material Instructions for Use (IFU), using polymeric materials approved for in situ lining of service pipes. Application of lining material to plastic pipes will only be allowed if the material has been specifically approved for this purpose and this approval is included in the relevant IFU which is listed in the Approval Confirmation letter for the lining material confirming the Regulation 31 approval.

These Operational Requirements currently apply to, but are not limited to, the in situ application of polymeric lining material by forced air application technology. Alternative application methods will be considered on their merits and included in the Appendices of this document when required.

These polymeric materials are placed in situ using Approved Application Equipment (as defined in OR 1.3) to Service Pipe Elements (as defined in OR 1.3) of nominal ½ inch up to, but not including 3 inch (12.5 mm but not including 75mm) internal diameter or as limited by the IFU or the Approved Contractor’s method statement.

Compliance with these Operational Requirements is a legal requirement for the in situ application of polymeric coatings to service pipes.

Material-specific information and advice is presented in the Instructions for Use (IFU) document provided by the coating material manufacturer.

It is the responsibility of the Water Undertaker to ensure that all practices conducted on the distribution system pose no risk to the quality of the water supplied. Failure to supply water fit for human consumption can result in the Water Undertaker being prosecuted.


The document has not been reviewed for its continued currency since publication.

Issue 1 required updating to incorporate amendments required by the Drinking Water Inspectorate.

One or more ‘Common Editorial Caveats’ apply – see ‘WIS & IGN Library / Navigation & Caveats’ for details.

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