FWIW; I've been using PVC in my shop for about ten years now with no problems. I don't know what schedule it is, but I got it from Home Depot and its marked at 480PSI.
A friend of mine who happened to work for an automobile company which shall remain nameless used their testing facilities to find out what happens when PVC is over-pressured. A 2" piece was capped off and placed in an enclosure with a glass view. Air was pumped in at increasing pressures until at about 600PSI the side of the PVC started to balloon. A few more pounds and the balloon split. That was it, no shrapnel, no explosion, just a split. (Chuck if you're watching feel free to correct my number. It might not have been quite that high).
YMMV. Something I think about is that all plastics seem to get brittle with age, which could seriously hamper their strength and result in that shrapnel we hear so much about. I've considered a simple shield over the pipe that would deflect any shards.
Larry Prince
Ridge Custom WoodWorks
Ypsilanti, MI
All opinions contained herein belong to Suzy. I had absolutely no input whatsoever.