NSF REG4 Certification

Demonstrate plumbing product and material compliance with the UK’s Water Supply (Water Fittings) regulations and byelaws through a fast, efficient, robust process.

If you’re a manufacturer of fittings and materials that come into contact with drinking water, you may have heard that, to have access to the UK market, your products need to be WRAS-approved.

However, that’s not quite correct.

A certification is a straightforward way to provide assurance to consumers, installers, and water inspectors that water fittings and materials comply with water regulations. Although it’s not mandatory in the UK, it’s crucial to have one if you want to be competitive in the market.

Map for WRAS-approved UK regulations and byelaws

The approval, however, doesn't need to come from WRAS. The reason for this misconception is that, for a long time WRAS was the only formalised approval in the market to showcase compliance with UK regulations and byelaws, including:

  • Water Supply (Water Fittings) Regulations 1999
  • Water Supply (Water Fittings) (Scotland) Byelaws 2014
  • Water Supply (Water Fittings) Regulations (Northern Ireland) 2009

Now, there are alternative ways to show compliance – like NSF REG4 certification.

Why choose NSF REG4 over WRAS Approval

NSF REG4 certification shows regulatory compliance in the same way WRAS Approval does, but with significant added benefits.

Faster and simpler process

As an approval body, WRAS doesn’t have the capability to test products internally. Before you apply for approval, you will need to have your products tested by an accredited third-party laboratory.

Applications are then reviewed at the next available PAAG meeting, which is held once every 4-6 weeks. However, the deadline for submitting the applications is typically 20 days before the meeting date. If you miss the deadline, you will have to wait until the next session. The product could be returned for additional review/testing, prolonging the approval process further.

All these steps delay your access to market and cause a loss of revenue.

NSF REG4 approvals are typically 4-6 weeks faster. That’s because NSF is in control of the whole process in-house. Product and materials testing is done in our laboratory in Wales and the results are separately assessed by our in-house technical team. If the results are in line with the NSF REG4 certification program, your approval is confirmed by our own experienced staff without the need for a PAAG meeting.

Ongoing support

With WRAS Approval, if test results show that there are non-conformances, you will have to resolve them and test again before applying. Also, when the validity of the certification lapses after five years, your product will be automatically de-listed unless it’s retested on time. If you have several products on the market, each one with its own certificate, it can be challenging to keep track of all the deadlines.

NSF REG4 customers receive assistance before, during, and after the certification process. Our UK-based account managers will be there to solve any compliance issues directly with you and we will remind you when a product is up for re-testing, so you don't need to worry about keeping track of deadlines.

Reliable tests and processes

NSF’s facility in Wales is the only ISO/IEC 17025-accredited laboratory that can perform both mechanical and material tests for water fittings under one roof. Also, our certification body status has been formally accredited by UKAS to ISO/IEC 17065, which certifies the competence and impartiality of the NSF REG4 certification scheme.

Service bundling

A WRAS certificate only covers the requirements of Regulation 4. If your products and materials need to comply with other UK standards—for example, Regulation 31 for products used by water suppliers or EN 200 for sanitary tapware—or with standards of other countries, you would have to go through another approval process with a different certification body.

Because we have offices, laboratories, and auditors globally, we can bundle all certification tests that you need—including R&D tests—into one single project, saving you time and money.

Two types of NSF REG4

NSF offers two REG4 solutions tailored to meet your needs: NSF REG4 S3 and NSF REG4 1+.


The requirements of NSF REG4 S3 are similar to the industry standard – a product’s certificate is valid for 5 years, at which point it must undergo a full re-assessment which includes full re-testing. There is no facility audit requirement.


With NSF REG4 1+, the product—if unchanged—is consistently approved on a rolling basis and an annual audit of the production facility is required. While NSF REG4 1+ involves an ongoing auditing and testing effort, it provides an additional layer of quality control on the facility and the products, increasing supply chain transparency and confidence for your customers.

Testing Capabilities

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  • The certification process was very smooth compared to other options. Being able to speak directly with NSF's technical team helped clarify technical questions, which dramatically shortened the timeframe.

    Ingo Hoffmann
    Manager Approvals, Meiko Group
  • We chose NSF REG4 without hesitation. We believe this certification will open new business opportunities and help us with improving our customer satisfaction levels. We definitely recommend working with NSF!
    RPE Srl – Italy

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