Posted in Water Regulations Advice and Interpretations

Contamination: Outside Taps
An outside tap – regardless of risk – should be protected by a double check valve.
The additional of a hose pipe that could potentially be submerged in water (such as tanks, ponds, swimming pools or rivers), creates the risk of backflow and therefore contamination to the mains.
As a guideline:
Any hose pipe used in a domestic setting would be fluid category 3 and therefore protected by a double check valve within the thermal envelope of the building.

Due to the higher potential risk of the fluids used in a non-domestic setting, as a guideline any hose pipes here would be considered a fluid category 5 risk and you would therefore need a physical air break in the system.
Do Consider –
·         The water companies take a risk assessed approach, and depending on the application, this could be downgraded
·         The addition of any chemicals or pesticides would exacerbate the risk
·         Bin stores, regardless of location, are fluid category 5
·         Irrigation systems with porous hoses that use no chemicals are considered a fluid category 4 risk and can be protected with a DB Pipe Interrupter
·         Whilst it is important to use hand held spray guns with self-closing mechanisms to prevent waste and misuse of water, these do not protect against contamination, and appropriate backflow prevention devices must be installed
As manufacturers of backflow prevention devices, we have a range of products and want to help find a solution for every application. Call us today.