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It has been my habit to use Christy's Red Hot Blue Glue to mend PVC pipe.

I am happy with the performance and the repairs turn out very well.

I also note, with great interest, that it is rated for potable water pipes (NSF pw-G-dwv-sw).

Recently, I constructed a long water conduit with schedule 40 potable water PVC pipe (NSF-61). The pipe sat, unused, for a month or so, and we used an air compressor to test it (ONLY TO 60 PSI, CALM DOWN ...) and when we let out all the air, it smelled like an open can of PVC solvent. Very, very strong smell.

OK, no big deal.

So I filled the pipes with water and let it sit for a few days. Then we drained all of that water out. Then we filled them with water a second time and let it sit for a few days.

When we ran the spigots to drain this second flush of water, the water had a strong and distinct smell of PVC solvent. Not terrible, but strong enough to notice.

So my question is this:

On a regular basis plumbers and pump and well guys and other contractors will fix potable water systems with PVC solvent and put those pipes into almost immediate use for drinking water.

Why is this OK ? If I can dry it out fully and then double flush it (sitting for days each time) and still smell the solvent, that means there is solvent in the water and that means people are drinking it.

Why is this OK ? Why should I ignore and/or not care about this ?

Thanks.

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    I'm not sure anyone has said it was ok besides you in this post ;) but that said, I'm now curious too. I would suspect it is because it gets diluted for one, but I agree, that doesn't mean it is safe. It also has to be used as intended. All water lines "are supposed to be flushed for x minutes" before first use after work has been done. There are a number of factors at play. You pressurized the line and then left it pressurized - under pressure, you prevented it from curing properly. Did you use it in excess of what was needed? Use it sparingly, and on the edges, and RUN water, not soak water – noybman Jun 24 at 3:50
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    Just to clarify, the pipes sat empty and unpressurized for weeks before we connected the compressor and pressure tested it ... so we did not interfere with the curing by pressure testing it ... – user227963 Jun 24 at 3:58
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    Like so many plastics it takes time to outgas, your nose is an amazing detector of some smells, plastics and things like Mercaptan we can smell at a few parts per million and mercaptan is considered non toxic, so it may be a case of our sense of smell being sensitive to certain things and some people are more sensitive than others. I have done my own plumbing and built remodeled many homes and all I do I’ll let the water run for a couple of minutes , I have never heard of problems , but remember we used to use lead pipes and now know that lead is hazardous to your health. – Ed Beal Jun 24 at 13:20
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    Based on the title, I was envisioning someone drinking PVC solvent straight from the can and that this was apparently a common practice. I am relieved. – Eric Hauenstein Jun 24 at 20:36
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    I've edited the title to something more sensible, but I'm also voting to close. First, the question asserts several things that aren't necessarily true. Second, it's mostly a matter of risk tolerance, which is subjective. Had the question asked about advised procedures for flushing new plumbing we'd have something useful to the community here. – isherwood Jun 25 at 12:52
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Your different methods are causing you to notice the smell more than normal.

I'm making a few assumptions, but if you create an airtight PVC pipe, where did you expect the glue to off-gas? It's going to fill the inside of the pipe, especially if left for weeks. The air volume of the inside of the pipe is pretty small, so it's a high concentration. You probably shouldn't be breathing in the test pressure exhaust when you vent it.

Next you said you "flush" it for several days, but filling a pipe with water and letting it sit, then draining it, and doing that twice isn't a flush. Again I'm making assumptions, but that's what it sounds like you did. Run fill pressure water through the pipe for several minutes with it going to drain to actually flush it.

The volume of water sitting in a pipe is miniscule compared to running water.

I don't disagree, PVC glue and primers aren't good for you. We all just "waste" more water than you to rinse the pipe more, so we probably don't notice it.

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