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BS 6920 Testing DWI Regulation 31 Consultancy Home
DWI Regulation 31 Testing  
Secretary Of State Listing is required for products and materials designed for the collection, treatment or distribution of drinking water, and is controlled by the Drinking Water Inspectorate (DWI).

Typically DWI Regulation 31 approval will involve: 

1. WRAS/BS6920 - Tests of Effect on Water Quality.

2. Specific Analytes
based upon  product formulation and method of manufacture.

The approvals process is as follows:

  • Application for Approval to DWI
  • DWI assess application
  • DWI inform laboratory of test requirements (confidential)
  • Test laboratory provide a quotation for testing
  • Test laboratory undertake testing and produce test report
  • DWI review the test report
  • DWI makes a recommendation for approval of the product to the Secretary of State, if appropriate
  • DWI issues an approvals letter and the product is incorporated into the list of "Approved Products and Processes"

Unlike the Water Regulations Advisory Scheme (WRAS) Tests of Effect on Water Quality, which are voluntary for products used in domestic building water systems, all products used by water supply companies in connection with public drinking water have to be assessed against the appropriate requirements of Regulation 31.  

[Advice and Approval - Guidance to Applicants]

Thames Water Utilities 2005