backflowpreventer中文

A backflow prevention device is a valve that prevents potentially harmful polluted water from entering the city’s drinking water supply when an incident such as a drop in pressure causes water to be drawn back into the main from private properties.

backflowtesting是什么

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A backflow of water can occur when there is a change of water pressure due to events such as a burst water main or firefighting operations causing the water to flow backwards from a private property into the main water supply.