A backflow preventer is used in a potable water piping system to prevent contamination from reversing into the clean water supply. It is crucial for maintaining water quality and preventing health hazards.
The purpose of a backflow preventer installed on a branch of a potable water piping system is to prevent backflow of water from the fixtures, appurtenances, and appliances connected to that branch from entering the other mains or branches within the building. This device ensures that contaminated water does not reverse flow and mix with the clean water supply, which could lead to health hazards.
Air-filled tubes in plumbing, often found near water faucets, prevent backflow as well by allowing air into the system if a vacuum occurs, thus preventing water from being drawn back into the clean water supply.
In the context of wastewater treatment, the primary objectives are to remove solid and organic matter, kill harmful bacteria, and reduce pollution caused by wastewater. However, the treated wastewater is not typically made clean enough to be considered potable or drinkable water directly after treatment.