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Demystifying Materials Approval

for Potable Water Systems: Understanding KIWA, NSF, and WRAS

In the realm of potable water systems, ensuring the safety and quality of materials used is paramount. Our customers often seek reassurance through certifications like WRAS (Water Regulations Approval Scheme) Approval when it comes to non-metallic materials in contact with drinking water (and demonstrating compliance with UK Water Regulation 4). However, the landscape of certification bodies can be complex. Let's delve into this topic to shed light on the roles of KIWA Watertec, NSF International, and WRAS.


Understanding KIWA Watertec and NSF International

KIWA Watertec and NSF International are ISO 17025 UKAS accredited testing laboratories, and one of their service offerings is testing and certification of plumbing products for potable water systems. They rigorously evaluate products for compliance against standards like BS 6920, which defines requirements for the suitability of non-metallic materials in contact with water intended for human consumption. Once products demonstrate meeting or exceeding this standard, KIWA and NSF issue product approval certificates under their own certification schemes, affirming compliance with stringent criteria for maintaining water quality.


The Role of WRAS

WRAS, formerly known as the Water Regulations Advisory Service, has played a role, but only in the certification process. When products undergo testing (and certification) by KIWA or NSF, WRAS may also review their test results and issue approval certificates under its own WRAS certification scheme.


Water Regs UK and the Evolution of WRAS

In recent years, WRAS has undergone changes, leading to the emergence of Water Regs UK, with WRAS Ltd (Water Regulations Approvals Scheme) as an owned subsidiary and, recently, a ISO 17065 accredited approvals Certification body. This allows Water Regs UK to focus specifically on regulatory matters, while WRAS Ltd continues to handle product certification.


A Choice of Certification Scheme

When it comes to selecting a test-house/certification body, manufacturers therefore now have several options. While WRAS Approval remains widely recognised, certifications from KIWA Watertec and NSF International offer entirely equivalent levels of assurance. Each is fully accredited to the relevant International Standard as both a Test House and a Certification Body. Meanwhile, WRAS Ltd is accredited solely as a Certification Body. It's important to note that WRAS does not conduct any product testing, a practice that has been consistent even in its previous form.



In conclusion, navigating the landscape of material approval for potable water systems requires understanding the roles of certification bodies like KIWA Watertec, NSF International, and WRAS. While WRAS may oversee the certification process and issues approval certificates, KIWA and NSF conduct rigorous testing and certification under their own schemes. Whether manufacturers choose WRAS, KIWA, or NSF approval, customers can trust in the integrity and safety of materials used in our products for potable water systems.

View our complete list of current Product Approvals.