NSF has today announced that it has received accreditation from the Drinking Water Inspectorate (DWI) for its Oakdale laboratory which becomes the UK’s sole facility offering comprehensive BS 6920 and REG 31 product testing, closing a critical drinking water safety gap.

The accreditation positions NSF’s Oakdale laboratory as the only facility in the United Kingdom capable of delivering both BS 6920 and REG 31 testing services, effectively closing a three-year gap in the nation’s drinking water safety infrastructure that has affected hundreds of manufacturers and water suppliers.

Since 2023, the UK has faced a significant challenge due to the absence of an accredited leachate testing laboratory. The gap has created a bottleneck in the REG 31 approval process, resulting in a backlog of hundreds of product approval applications and forcing repeated extensions of existing certificates without the requisite testing, potentially compromising water safety and hindering innovation in the market.

Vincent Boks, Vice President, Water at NSF commented:

“NSF’s full REG 31 testing accreditation represents a significant advancement for drinking water safety. For the past three years, manufacturers and water suppliers have struggled with limited testing capacity, creating unnecessary risks and delays. NSF’s comprehensive in-house capabilities will help manufacturers navigate the REG 31 approval process, while ensuring the highest standards of public health protection for the 55 million people served by public water supplies in England and Wales.”

REG31, established under The Water Supply (Water Quality) Regulations 2016, mandates that all materials and products in contact with public drinking water, from source to property boundary, meet stringent safety standards. Compliance is compulsory for all UK water companies, making REG 31 approval essential for manufacturers operating in this sector.

NSF’s Oakdale facility, accredited to ISO/IEC 17025 standards, is among the world's largest specialised water testing laboratories. It offers manufacturers a single partner for all required testing for REG 31, including BS 6920 testing as a precursor requirement before seeking full REG 31 approval, along with a wide range of UK-specific and European approvals, conducted entirely in-house by experienced engineers and scientists.

Simon Hubbard, Senior Director, Global Laboratories at NSF added:

"Recent enforcement actions, including a £1.42 million fine for REG 31 violations[i], highlight the critical importance of compliance in protecting public health and maintaining industry integrity. Our investment in Oakdale’s REG 31 capabilities reflects NSF’s commitment to delivering rigorous, reliable testing solutions that mitigate regulatory and reputational risks. By restoring full REG 31 testing capabilities to the UK, we enable manufacturers to confidently meet compliance requirements, safeguard water quality and help drive innovation forward.”

NSF’s REG 31 services address key market challenges, including regulatory complexity, laboratory capacity limitations, and financial and reputational risks from non-compliance. The services cover all relevant product categories, including pipes and fittings, coatings and linings, tanks and reservoirs, treatment chemicals, filter media and membranes, and cements, resins, and repair materials.

Manufacturers seeking REG 31 testing services are encouraged to contact NSF immediately at This e-mail address is being protected from spambots. You need JavaScript enabled to view it to initiate the approval process.