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How'd you get so smart???

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yep i'm an inspector, and i have inspected/audited several pipe/fitting manufacurers in the US and Canada. I work for NSF International which is the certifying labratory. NSF (formerly the National Sanitation Foundation) is an independent labratory (much like UL, CSA, ETL, etc). Anyway I audit the manufacturing practices, QA/QC practices, and materials and ingredients stuff is made out of, the proportions, and physical specs to the appropriate ASTM. I collect all kinds of samples and send them to our Ann Arbor, MI headquarters that performs the physical tests and chemical extraction tests in a controlled environment that is compliant to ASTM standards...
hope that explains a little more.
NSF International --- Live Safer! ---your public health and safety company.
anyway, when I saw the note about dwv pipe used for pw, it spooked me because i've seen the test results of these... you don't want to ignore a designation like this. dwv does not mean it's the same stuff as pw....
tk