Page 310 - Water Engineering Hydraulics, Distribution and Treatment

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Chapter 9
Cross-Connection Control
Reduced pressure
principle backflow
preventer
Main
(a)
Reduced pressure
principle device
Water meter
Air gap
Drain
12˝ min. 30˝ max.
Note: Device to be set 12˝ minimum from wall.

(b)

Siamese
Siamese check
fitting Alarm check

Grade

Double check valve

OS&Y gate valve

Figure 9.28 Reduced pressure
Fire pipe
device installations in (a) car
wash, (b) water supply line, and
(c) fire line. Conversion factor:
(c) 1 = 1in. = 25.4 mm.
′′