Regulations Concerning TMV and RPZ Valves.
Artius PP are one of the qualified and accredited testers of TMV and RPZ valves in the UK, our service of testing and installing TMV and RPZ valves covers the whole of the UK.
Reduced Pressure Zone valves
Backflow from fittings or appliances resulting in unwholesome water passing into drinking water supplies can constitute a serious public health hazard. There are numerous, well documented cases where backflow has resulted in contamination incidents which were harmful to health. The risk is a continuous one because plumbing systems are frequently being installed, altered or extended.
Prevention of backflow requires thorough knowledge and continual vigilance. Awareness is essential and even those who are experienced in plumbing systems may fail to recognise potential backflow and cross-connection situations. Those responsible for the water supply in their premises must be familiar with the potential risks from backflow and cross-connections and must carefully monitor their systems.
The Regulations state that RPZ valves must comply with the requirements for water fittings (Regulation 4) and must be installed ‘in a workmanlike manner’. One way of complying with the ‘workmanlike manner’ requirement is to conform to a method of installation approved by the water supplier.
Commissioning and testing of an RPZ Valve must only be carried out by an accredited tester approved by the water supplier as being competent to test.
It is a criminal offense to contaminate the water supply or to use fittings which cause or are likely to cause contamination. This applies equally to backflow causing contamination of water in the water supplier’s mains or in the customer’s premises before use.
The installation and use of an RPZ Valve requires a long-term commitment to testing and maintenance on a regular basis. Test methods and maintenance regimes must be in accordance with the water supplier’s requirements. Failure to comply with these requirements increases the risk of contamination by backflow and may result in the water supplier temporarily suspending the supply.
Artius PP can help, advise, install, commission, test and maintain your Reduced Pressure Zone (RPZ) valve.
Read more about the Water Regulations Advisory Scheme here
Thermostatic Mixing Valves
Legionella bacteria is commonly found in water. The bacteria multiply where temperatures are between 20-45°C and nutrients are available. The bacteria are dormant below 20°C and do not survive above 60°C.
Legionnaires’ disease is a potentially fatal type of pneumonia, contracted by inhaling airborne water droplets containing viable Legionella bacteria. Such droplets can be created, for example, by: hot and cold water outlets; atomisers; wet air conditioning plant; and whirlpool or hydrotherapy baths.
Anyone can develop Legionnaires’ disease, but the elderly, smokers, alcoholics and those with cancer, diabetes or chronic respiratory or kidney disease are at more risk.
What you need to do
Health and social care providers should carry out a full risk assessment of their hot and cold water systems and ensure adequate measures are in place to control the risks.
Using temperature control
The primary method used to control the risk from Legionella is water temperature control.
Water services should be operated at temperatures that prevent Legionella growth:
- Hot water storage cylinders (calorifiers) should store water at 60°C or higher
- Hot water should be distributed at 50°C or higher (thermostatic mixer valves need to be fitted as close as possible to outlets, where a scald risk is identified).
- Cold water should be stored and distributed below 20°C.
A competent person should routinely check, inspect and clean the system, in accordance with the risk assessment.
Click here for more information on Managing legionella in hot and cold water systems.