(FAQ1) – How do I apply for approval of my product(s) for use with public and private drinking water supplies


All the information you need to enable you to submit an application for approval of a product under the requirements of the relevant regulations to the Drinking Water Inspectorate (DWI) is provided on the DWI Website – initially you are recommended to refer to  Advice and approval – Drinking Water Inspectorate (dwi.gov.uk) together with the linked documents.   The DWI operates the approval scheme on behalf of all the United Kingdom Authorities. Listed below are the main documents you will need to read and use for your application.

The Application Process

An overall view of the application process is provided in Figure 1 Overview of approval process

There are four critical aspects of preparing an application for submission to DWI.

  1. Preparation
    Ensure that when applying for approval that the application you are making is for a product that will be used by a public or private supplier of drinking water in the United Kingdom, as these are the only products that can be considered. Before submitting your application to us ensure it is complete and all the paperwork required is available. Incomplete applications or insufficient information will delay the application process. It is essential that you read Advice sheet 1 – this advice sheet outlines the approval process and it can be found on the Advice and approval – Drinking Water Inspectorate (dwi.gov.uk) webpage.
  2. Instructions for Use (IFU) document
    It is essential that you have an IFU document that conforms to the requirements set out in our Advice Sheet number 2 – IFU . You will need to submit the IFU as part of your application documents – this document will be an integral part of any approval finally given for your product. Failure to submit a satisfactory IFU will delay the progress of your application
  3. Completion and submission of the appropriate Application Form
    You will find a range of Application Forms designed for use with specific product types on the website Advice and approval – Drinking Water Inspectorate (dwi.gov.uk). For any other products use the “Non-metallic Construction Product” application form – dwi.gov.uk/wp-content/uploads/2020/12/15092524/General1.doc
  4. Support and co-operation of your supplier
    In order to be able to supply DWI with all the formulation details of all materials incorporated into your product(s), together with all relevant Material Safety Data Sheets, you will usually have to rely on the co-operation of your suppliers. Often they will need to submit confidential formulation details directly to DWI. The supply of this information will take time and could delay the progress of your application. It is vital, therefore, that you inform your suppliers using the letter provided.

    If your suppliers are concerned about confidentiality refer them to our FAQ 3 – ‘Can the DWI enter into a confidentiality agreement concerning product ingredients?’ FAQs and Letters – Drinking Water Inspectorate (dwi.gov.uk)

Use of Experienced Consultants

In view of the comprehensive nature and the potential complexity of the information required in support of an application for approval, you are strongly recommended to use a consultant who has experience with the requirements of national regulatory authorities to assist you in preparing your submission documents. The DWI is not able to offer a consultancy service to assist you with your application, nor is it able to help in resolving any outstanding issues or omissions in your application documents. However, the designated test laboratories should be able to assist you with this, although you are free to use other consultants.

Important Note: neither DWI, nor its advisers, can take responsibility for delays in the processing of applications resulting from failures to submit all the information required at the time of application, or failure to submit any further information requested in a timely manner.


Your completed Application Form, IFU, and the supporting documentation should be submitted electronically to DWI – reg31.enquiries@defra.gov.uk . If this is not possible it can be submitted by post, but in this case please send an electronic copy on a CD-ROM as well as a hard copy.

Cost & Time Implications

The following information is provided for guidance only, since each product will be considered by DWI on a case-by-case basis –
a) submission and consideration of your application by DWI, together with the release of test requirements and the final review of the leachate study test report – Details of the administrative charges are given in section 3.6 of advice sheet 1 and a summary is indicated in the flow chart at the end of this FAQ.
b) consultancy to assist you with your submission – you will need to ask your chosen consultant for an indication of the likely cost of this;
c) full BS 6920 testing of non-metallic materials used in your product (if required) – the likely cost could be in the region of £800 to £900 for each material – you should obtain an estimate of the likely cost from one (or more) of the designated test laboratories
d) preparation and analysis of leachates from your product – this will be dependent upon the nature and the proposed use of your product, but for most construction products it is unlikely to be less than seven to eight thousand pounds and could be significantly higher than this; once DWI has considered your application and released the test requirements, you should approach one or more of the designated test laboratories for an estimate of the cost of undertaking the testing requested.

Since each product is considered on a case-by-case basis it is impossible to give a specific time period to deal with an application, from the initial submission to evaluation of test results. Past experience has shown this can vary from one month to several months and, for potentially high risk products, has taken several years (in cases where new toxicological data had to be obtained). If the product is potentially of low risk and all the application details, plus the supporting information (such as the IFU and any required testing) complete and adequate upon receipt, the DWI could reach a decision within weeks.

The DWI cannot take responsibility for the time taken by the applicant (and any of the applicant’s suppliers) to submit a completed application of sufficient quality.

Please note that on the basis of the test results obtained for the product, the DWI reserves the right to ask for additional information and/or additional laboratory testing.

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