Systems & Code第 57 / 110 题
A single-family residence has an underground lawn sprinkler system with no chemical injection and no downstream pressure. This is a low-hazard, backsiphonage-only condition. Which is the minimum acceptable backflow device?
a.Atmospheric vacuum breaker installed at least 6 in above the highest head
b.Reduced-pressure principle assembly
c.Air gap only
d.No device required
解析
For a residential sprinkler with no chemicals and no backpressure, an atmospheric vacuum breaker installed at least 6 in above the highest downstream head (sprinkler) is the minimum acceptable device. It protects only against backsiphonage and must not be under continuous pressure for more than 12 hours. Adding chemicals or downstream pumps would escalate the requirement to an RP assembly.
法律依据: UPC §603.0免费刷完整 110 道题库 — 无需注册。
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