If you use PVC, wrap it with a copper wire or something and ground it. I've never seen or heard of it happening but, there is concern of the static electricity buildup inside the plastic tube setting off an explosion in the sawdust. I used tin stove pipe to run my ducts. Vac is in the corner, duct runs overhead to the arm saw and a long flexible piece drops from the middle of the gtarage to be hooked up as needed. If you are going to stick the vac out of the way, invest in a remote switch. I ran some wires to a DC relay that starts the vac and put a few stitches around the shop. You can get a nifty wireless setup and keep the clicker in your pocket but, the clicker was almost as much as the vav.
I never noticed it being that lound. Not any louder than an arm saw or my sander. Then again, all those years on a motorcycle might have made me deaf
-David