The IGN superseded IGN 4-50-01 & IGN 4-50-02. It explained the corrosion mechanism & provided guidance on when PE sleeving should be applied to ductile iron pipeline systems. Its parts address: general requirements for factory and site applied PE polymeric sleeving; tubular polymeric sleeving for site application; factory application.

The IGN superseded both IGN 4-50-01 and IGN 4-50-02. Its contents reflected then current guidance in BS 6076, BS EN 545 and IGN 4-21-01.

Caveats

The WUK Standards Board commissioned a review of IGN 4-50-03 that concluded in March 2023. Based on the review’s findings the Board determined that the document’s status should be changed from ‘current’ to ‘archived’ since:

• IGN 4-50-03 was written in 1996 and has not been updated since.
• Of the four British Standards and international standards/guides referred to in the IGN, two have subsequently been withdrawn and BS EN 545 has been revised at least once.
• Given their disparity in publication dates IGN 4-50-03 may also conflict with ISO 8180:2020 – Ductile iron pipelines- polyethylene sleeving for site applications.
• Ductile iron pipe manufacturers have developed a range of corrosion protection systems which differ from those described in IGN 4-50-03 and polyethylene sleeving is no longer offered as a standard product by either of the two main suppliers of ductile iron pipes in the UK.
• Corrosion protection systems offered by the ductile iron pipe manufacturers have evolved with standard external coatings including a zinc-aluminium galvanic layer covered by an epoxy. A range of protection systems are offered for more aggressive ground conditions and pipe fittings tend to be offered with a fusion bonded epoxy coating. The range of corrosion protection systems recommended by the ductile iron pipe manufacturers no longer includes PE sleeving.
• As a result the guidance in the IGN now contradicts the advice offered by the two main suppliers of ductile iron pipes and fittings to the UK.
• The view of the BSI committee responsible for ductile iron pipes and fittings (PSE/10) is that IGN 4-50-03 should be archived.

The need for an update of IGN 4-50-03 appears low. There appears to be insufficient appetite from the two main ductile iron pipe manufacturers to fund an update. However, others have suggested it would be useful to have up to date guidance on ductile iron pipe systems, covering areas such as corrosion protection systems and their limitations, anchored jointing systems and their limitations and when internal seal coats should be specified. Another issue is the need for guidance on how to specify iron pipes when clients require a 100-year design life. Producing such guidance would be a significant undertaking requiring support from pipe manufacturers and water companies.

In the event of a consensus on the need for preparation of a new IGN the Standards Board would require the parties involved to form a Task & Finish Group to that end. For further information on how achieve this contact the Board’s Technical Secretary here.

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