I came across a white pipe off of a tpr valve today that looked just like pvc. Of course, I thought it was wrong but for some reason I knelt down to read the pink writing on it. It said it was rated for use as a pipe off a tpr for any unit up to 100,000 btu's.

I snapped several pictures but, as most of you can relate to, trying to snap a picture of small pink writing on a small white pipe doesn't always work.

It wasn't stamped with any recognizable brand or type of pipe, just that it was okay for use as I noted above.

Has anyone run into this stuff? If so, what is it? I've just always assumed when it's bright white it's pvc.