Systems & CodeCâu 56 / 110
A boiler feed with chemical treatment connects to potable water. This is a high-hazard connection. Which assembly protects the potable supply against backpressure from the pressurized boiler?
a.Atmospheric vacuum breaker
b.Dual check valve
c.Hose-bibb vacuum breaker
d.Reduced-pressure principle backflow assembly
Giải thích
A chemically treated boiler is a high health hazard under backpressure, so a reduced-pressure principle assembly is required because it alone protects against backpressure of a health hazard. Atmospheric vacuum breakers cannot be used under continuous pressure or against backpressure. The RP relief port provides a visible, fail-safe break.
Trích dẫn luật: UPC §603.5.7Luyện miễn phí toàn bộ 110 câu hỏi — không cần đăng ký.
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