Water Supply Industry Interpretations and Advice

  • Area of Interest : Backflow prevention
  • Topic : Fluid category
  • Title : High risk tap installations 
  • Clause Reference : Schedule 2 paragraph 15 & G15.3
  • Reference Number : B34
  • Decision Date : May 2005 (revised June 2015)

Taps used in high risk installations, such as kitchen sinks, are considered to be a fluid category 5 risk. Backflow protection is usually provided in the form of an AUK3 tap gap.

Where an AUK3 tap gap cannot be maintained, for example where the tap gap is compromised as a result of:-

  • the tap being lowered in any way;
  • adjustment to the spout which reduces the distance between the tap outlet and spillover level of the sink; or
  • the operation of a pull out hose attachment

alternative fluid category 5 backflow protection is required.