Water Regs UK publishes revised guidance on RPZ valve installations

 Following  public consultation a new version of  the approved installation method for RPZ valves (backflow prevention devices) or RPZ AIM for short, came into force on 1^st January 2025. 

 The RPZ AIM sets out how to install and test RPZ valves to comply with the  Water Supply (Water Fittings) Regulations, Byelaws in Scotland. These legal requirements apply to all premises which have, or will have, a mains water supply. They aim to safeguard drinking water supplies by preventing contamination, waste, misuse, undue consumption and erroneous measurement.

 The new edition specifies new minimum requirements for RPZ test equipment (full details of these are published separately here) and clarifies acceptable methods of testing, as well as requiring RPZ valve testers to periodically demonstrate competence.

• New requirements for test equipment:

  • There is a new minimum specification. RPZ valve testers have until 30^th June 2026 to replace test equipment not meeting this new requirement.

  • Testing using a single tube manometer is no longer acceptable from 1^st January 2025.

  • Until 1 Jan 2026 RPZ testers can use a U tube manometer providing  they follow the procedures specified in either Regulator Test Code Sheet TCS 1111.13 or clause 9.5.2 of BS EN 12726:2023.

• RPZ valve testers are required to demonstrate their competency by revalidating their qualification every 5 years, this will typically be done by reassessment rather than retraining.

  • Those who qualified after Nov 2021 – should revalidate their qualification every 5 years from their certification date.

  • Those who completed the conversion training prior to Dec 2020 – should revalidate their qualification by 31 Dec 2026

Paul Millard, Technical Manager for Water Regs UK, says:

"These updates will improve overall standards and ensure accurate, evidence-based measurements and testing is undertaken going forward. They also ensure the UK is aligned with the good practice adopted in countries with a longer history of RPZ valve use and testing, including Australia and the USA.

“We’re keen to make sure that those involved in any way with ongoing testing of RPZ valves are clear about their roles and responsibilities. The changes implemented allow sufficient time for respondents to meet the new requirements and we encourage testers to make sure they know what is expected of them ”   

On-site testing for RPZ valves should only be carried out by somebody who is fully trained and has a recognised qualification in RPZ valve commissioning and compliance testing.

For further information, visit www.waterregsuk.co.uk/guidance/rpz-faqs/ or for water company contact details: www.waterregsuk.co.uk/water-company/.