What products are permitted for use in private water supplies?
Products and substances that fall into one or more of the categories set out below may be used in a private water supply:
- List of approved products for use in drinking water supplies in the United Kingdom
- Products permitted under the "small surface area" rule (see DWI Advicesheet8)
- WRAS approved material (compliant with the fittings regulations)
- Treatment chemicals permitted under a BS:EN standard with appropriate conditions of use (Annex 2 of the list of approved products)
- Products included on the Transitional List maintained by the Drinking Water Inspectorate for England and Wales
Who is this information for?
The list of approved products is intended to help local authorities in providing advice to PWS owners on the products that may be used in their systems. Local authorities are the bodies responsible for enforcing the PWS regulations and the list is provided to them as part of DWQR’s remit to provide technical assistance and support. Suppliers may also wish to consult the list to ensure that their installations are able to comply with local authority requirements.
What is the transitional list?
Although a wide variety of products and substances have been used for many years in private water supplies, as yet very few have been evaluated formally for placing on the list of approved products and substances. For this reason, the Drinking Water Inspectorate for England and Wales has put in place transitional arrangements that allow some of these products to be included on the Transitional List.
Can I apply to have my product included in the transitional list?
Please see the guidance available on the website of the Drinking Water Inspectorate for England and Wales.
What else do I need to know?
Local authorities are required by the 2017 regulations to complete risk assessments for all Regulated supplies and to review these risk assessments annually. Additionally, local authorities must provide advice and assistance on risk assessments to those responsible for Exempt supplies on request. Ongoing management and maintenance of supplies are an integral part of the risk assessment process. Therefore any treatment system should come with an appropriate set of instructions for use and operation. This document should also detail any maintenance requirements, including the criteria and regime for the replacement of any products or substances. Reputable installers should provide a practical instruction and demonstration of the management and maintenance of the system to customers. We recommend that installers explain the importance of keeping management and maintenance records of any newly installed system to assist with the risk assessment process, required under the regulations.