ASME A112.1.2:2012 pdf free download

ASME A112.1.2:2012 pdf free download.Air Gaps in Plumbing Systems (For Plumbing Fixtures and
Water-Connected Receptors).
(b) Connect the inlet(s) of the faucet or device to a vacuum source. The vacuum shall be measured at the inlet of the faucet or device.
(c) A means to change the water level in the container relative to the outlet of the faucet or device shall be provided.
(d) Start the test with the water level at the mounting surface of the faucet or device.
(e) With the faucet or device fully open from its inlet(s) to point of discharge to atmosphere, apply a vacuum of 635 mm Hg (25 in. Hg) to the inlet(s). Backsiphonage at this time is cause for rejection.
(f) The water level shall slowly be brought closer to the discharge outlet of the faucet or device until the level at which backsiphonage occurs. At this point, record the water level. The distance between the water level and the lowest point on the discharge outlet of the faucet or device shall be measured and recorded.
(g)Return the faucet or device to atmospheric conditions.
(h) Starting with the water level higher than where backsiphonage occurred, apply a vacuum to the inlet(s) of 635 mm Hg (25 in. Hg). Slowly lower the water level until the backsiphonage stops. Maintain the vacuum foranother 1 min to be sure no more water is being drawninto the discharge outlet of the faucet or device.At thispoint, record the water level.The distance from the waterlevel and the lowest point on the discharge outlet of thefaucet or device shall be measured and recorded.
(i)The larger of the two distances measured andrecorded shall be considered the critical air gap of thefaucet or fitting.
(j)Repeat this test for another two sequences to con-firm the measured and recorded critical air gap.
(k)For faucets and devices with a critical level mark,confirm that the mark is at a level that is at or abovethe highest water level recorded in determining thecritical air gap.
NOTE: Faucets or devices that can be installed and have a near-wall effect [see Table 1, Notes (1) and (2)] shall be tested with thedischarge outlet of the faucet or device against one wall of the testcontainer.
2.4.2 Backsiphonage.With the water level at thecritical level mark on the faucet or device or at themandatory levels of Table 1 when the faucet or devicehas no mark, apply a vacuum of 635 mm Hg (25 in. Hg)to the inlet(s) of the faucet or device.Any indication ofwater at the inlet(s) shall be cause for rejection.