Skip to content
Secure Login


WIS 4-52-03 Issue 1 Specification for Anti-corrosion Coatings on Threaded Fasteners

The WIS specifies the requirements for factory applied anti-corrosion treatments for bolts, nuts & washers.

It is intended primarily to apply to buried pipeline applications, such as bolts used in flanges & fittings.

The anti-corrosion treatments covered are organic coatings which are adhered to the substrate, and which fully cover the item (inside threads on nuts, and jig marks of no more than 1mm width on the bore of washers, may be left uncovered). These coatings may be complete systems in themselves or may form part of a system together with sacrificial metals.


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

Based on the Standards Board’s enquiries of stakeholders (British Coatings Federation & BSI Committee PSE/10 – Autumn 2021) the consensus view is that the existing document would benefit from updating to reflect new classes of coatings and take out old ones no longer used.

PSE/10 members reported the WIS is used quite frequently. They felt there was unlikely to be an EN standard as these tend to focus on the core product rather than connection products but PSE/10 doesn’t contribute in this area. Two proprietary coating products are widely used.

The Board has therefore initiated a review of the WIS’s continuing relevance and currency. PSE/10 suggested the reviewer inspects the following ISO standards on bolts, washers & fasteners: ISO 4016; ISO 4034; ISO 7091; ISO 10683 for relevant content.

Respond to this WIS/IGN

Use the commenting form to make comments on an existing WIS or IGN. Upload your completed commenting form below. Please read the downloadable Guidance Notes before completing the commenting form. Comments received in other formats will not be considered.

Accepted file types: doc, docx, Max. file size: 10 MB.
Accepted file types: doc, docx, Max. file size: 10 MB.