Safety第 98 / 110 题
Backflow prevention is a public-health safety requirement. What health event does a properly working backflow assembly prevent?
a.Water hammer
b.Contaminated water being drawn or pushed back into the potable supply
c.Pipe corrosion
d.Frozen pipes
解析
Backflow protection prevents non-potable or contaminated water from entering the public drinking-water system through backsiphonage or backpressure, which has caused real disease outbreaks. The assembly is the barrier between a cross connection and the community's water. This is why high-hazard connections require the fail-safe reduced-pressure principle assembly.
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