Hi, the installer put what looks like insulation around the pipe that goes up the chimney so the heat does not go up the chimney as it was doing. He is coming back to put a plate on it and move the stove out further from the fireplace but is this safe to have the insulation just hanging there? Are we being exposed to the fibers and cancer etc or is fire wool different than regular insulation. Worrisome really but he needs to get a certain pipe with the exact length we need so left it this way til he puts new pipe length and then will put the plate up but want to make sure we are not killing ourselves with this set up.