[Answer] What is the only completely reliable method for preventing backflow?

Answer: 4 inches

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What is the only completely reliable method for preventing backflow? Backflow prevention device - Wikipedia Backflow prevention device - Wikipedia ServSafe Flashcards | Quizlet What is the only completely reliable method for preventing backflow ? 4 inches When installing tabletop equipment on legs the space between the base of … An air gap is the only completely reliable method for preventing backflow. Backflow Unwanted reverse flow of contaminants through a cross-connection into a drinkable water system. Air space used to separate a water-supply outlet from any potentially contaminated source. An air gap is the only completely reliable method for preventing back flow. (Ex.Air space between the floor drain and the drain pipe of a sink) The simplest most reliable way to provide backflow prevention is to provide an air gap. An air gap is simply an open vertical sp...

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