By Fred Bretzke
Fred Bretzke is a full-time pipe trades instructor with SAIT Polytechnic in Calgary. He can be reached at fred.bretzke@sait.ca.
PLUMBING
UP THE ANTE WITH
CROSS CONNECTION CONTROL CERTIFICATION
C
ross connection control is a very important part of public safety and never more so than during these pandemic times. In western Canada, it’s the Western Canada Section of the American Water Works Association (WCS AWWA) that is the governing authority of cross connection control (CCC). We saw it come to Calgary in 1984 while I was a fourth-year apprentice at SAIT. Since then I have been CCC-certified and I have taught the cross connection control course for many years. This is a handy certification to possess. As I tell my students, if you are CCC-certified you are an even more employable technician, especially if you own a CCC test kit.
THE DOUBLE CHECK VALVE ASSEMBLY (DCVA) DCVAs are typically used for premise isolation on commercial buildings. They are required for moderate hazards in non-health conditions. These devices protect the public water mains from any possible pollutants, including discoloured or distasteful water, cross connecting into them. You will find most DCVAs in the mechanical room just downstream of the water meter bypass. In order to explain how to repair these devices, one should first know the test procedure.
DCVA TEST PROCEDURE The following is the AWWA test procedure for a DCVA.
Let’s play CCC service technician for this article and see what we can learn. When it comes to CCC devices or repairs, it’s all about being transparent to customers. There are many devices but only three testable devices, which are tested annually, or on new installations, or reinstallations, or when repairs are made. These include the pressure vacuum breaker (most often used for irrigation systems), the double check valve assembly (DCVA) and reduced pressure (RP) backflow devices. For the purposes of this article, we’ll focus on the DCVA and the RP.
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M e c h a n i c a l
B u s i n e s s
Test Procedures for Double Check Valve and Double Check Detector-type Assemblies using a Differential Pressure Gauge Test Kit: Check Valve #1 and Check Valve #2 Performance Criteria: The check valves shall be loaded internally so that when the supply pressure is at least 1 psi and the outlet pressure is atmospheric, each check valve will be drip-tight in the normal direction of flow. [AWWA C510 Sec. 4.3.2.1]
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