IRN R575

Where owners or occupiers propose to use equipment for dosing of chemicals, such as chlorine dioxide, to maintain water supply quality in premises (e.g. to protect against the growth of Legionella bacteria), dosed water must remain wholesome if used for domestic purposes.

In accordance with schedule 2 paragraph 27 of the Water Supply (Water Fittings) Regulations 1999 in England and Wales, the Water Supply (Water Fittings) Regulations (Northern Ireland) 2009, and the Water Supply (Water Fittings) (Scotland) Byelaws 2014, a drinking water tap shall be installed upstream of this fitting. However, if it can be demonstrated that the water once it has passed through this water fitting remains wholesome and meets national standards, water suppliers may not require the installation of a drinking water tap upstream of this water fitting.

A compliant double check valve or some other no less effective device providing backflow prevention protection to at least fluid category three shall be fitted at the point of connection(s) between the water supply and the fitting or appliance.

However, where chlorine dioxide is generated in-situ for subsequent dosing then the generation equipment must have appropriate backflow protection. 

Notification should be given in writing of the proposed installation of this fitting to the local Water Supplier prior to its installation. The fitting shall not be installed until consent is given by the Water Supplier in line with Regulation 5 of the Water Supply (Water Fittings) Regulations 1999 or the Water Supply (Water Fittings) Regulations (Northern Ireland) 2009, or Byelaw 5 of the Water Supply (Water Fittings) (Scotland) Byelaws 2014.

The fitting is to be so installed as to be readily accessible for examination, test, maintenance, replacement or operation.

The product will need to meet the requirements of the current version of BS 12671. This Approval does not verify that this requirement has been met. 

Water Suppliers cannot be responsible for the quality of water passed from these fittings.


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