Water Supply & Distribution第 43 / 120 题
A potable water line supplies makeup water to a chemically treated boiler system and the connection is under continuous pressure. Which backflow prevention device is required?
a.Double check valve assembly
b.Atmospheric vacuum breaker
c.Reduced pressure principle backflow preventer
d.Hose bibb vacuum breaker
解析
Treated boiler water is a high hazard (health hazard) contaminant and the connection is under continuous pressure, which calls for a reduced pressure principle assembly. A double check assembly is only acceptable for low hazard, non-health, continuous pressure applications. An atmospheric vacuum breaker cannot be used under continuous pressure at all, and a hose bibb vacuum breaker is for hose outlets and protects only against back-siphonage.
法律依据: IPC §608.13免费刷完整 120 道题库 — 无需注册。
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