Backflow: Levels of risk




Backflow: Levels of risk

		The water utilities have a duty to supply water, which complies with the water regulations, and the water industry act 1991. This ensures the supply of clean wholesome water suitable for domestic or food production purposes. Drinking water should therefore be obtained direct from the mains water supply without any intervening storage before use. For the purposes of classification this quality of water is called 'fluid category 1' and is the category that needs to be protected against all forms of contamination and pollution.

There are four further categories that have an increasing degree of risk these are described below. Links are provided to the backflow prevention components that are acceptable under the new regulations.

Fluid category 2:		Examples would include:

Water that has undergone a change in taste, odour appearance or temperature. For example water that is heated for bathing, or is discharged from showers, or water that has been treated with a water softener using a salt regeneration process. These changes tend to be aesthetic only and therefore present no threat to human health. Click here to view suitable backflow prevention devices suitable for fluid protection category 2		Mixing of hot and cold water through appliances and taps Supply of water through a vending machine where no ingredients are added direct into the water supply such as carbon dioxide Domestic salt regeneration water softeners. Ice making machines Fire sprinkler systems, which do not contain additives. Water-cooled air conditioning units, which do not contain additives

Fluid category 3:		Examples would include:

Water that is a hazard to health and is not suitable for drinking, cooking or other domestic purposes. For example water that has been used for bathing. Click here to view suitable backflow prevention devices suitable for fluid protection category 3		Water present in central heating systems. Water used by dishwashers, washing machines, home dialysing machines. Water that has been used for bathing or showering. Garden hoses that have a flow control or shut off control. Garden hoses that are attached to fertilizer sprays. Domestic or commercial irrigation systems, without additives, sprinkler heads to be not less than 150mm above ground level. Vending machines in which ingredients are injected. Commercial salt regeneration water softeners .

Fluid category 4:		Examples would include:

Water that is a significant hazard to health due to the concentration of toxic substances and is not suitable for drinking, cooking or other domestic purposes. Click here to view suitable backflow prevention devices suitable for fluid protection category 4		Commercial central heating systems. Fire sprinklers that include anti freeze solutions. Mini irrigation systems that use pop up sprinklers or permeable hoses. Food preparation areas, dairies bottle washing etc. Commercial dishwashers. Car washing and degreasing plants. Industrial disinfection equipment .

Fluid category 5:

Examples would include:

Water that is a serious hazard to health due to the concentration of pathogenic organisms or toxic substances.

Click here to view suitable backflow prevention devices suitable for fluid protection category 5.