The NSF REG4 Certification for the UK Helps Plumbing Products Show Compliance
The NSF REG4 certification scheme for the UK market allows plumbing products and materials to show compliance with the Water Supply (Water Fittings) Regulations 1999.

NSF REG4 Certification & The Regulators’ Specifications
All manufacturers selling water supply products into the UK must meet Regulation 4, a section in these regulations:
- Water Supply (Water Fittings) Regulations 1999
- The Water Supply (Water Fittings) (Scotland) Byelaws 2014
- The Water Supply (Water Fittings) Regulations (Northern Ireland) 2009.
NSF RG4 is your solution to meet the Regulators’ Specifications.
The scope of this certification scheme includes mechanical products in contact with drinking water, such as valves, backflow prevention devices, taps, mixers, shower heads, pipes and fittings, tanks, cisterns, water metres and many others. It also covers non-metallic products such as rubbers, coatings, cements, resins and sealants.
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