Hi Clancy,
I had to work on a fixer-upper house that had asbestos insulation around the roof vents. I highly recommend that you wear a HEPA-rated mask even if you think that the tiles are not shedding and definitely if you use a heat gun (the fumes from the heating process can be toxic), because it's worth the extra protection.
Home Depot has HEPA masks (or used to) for about $40... they look like military gas masks.
Another thing to keep in mind is that there are many natural herbs and supplements that can assist our bodies in detoxing during and after exposure (which is absolutely not a replacement for protecting ourselves as best we can).
I try to do specific herbal cleanses preventively and concurrently when doing anything that might overly expose me to crud (i.e. repainting an old house, using spray paints, etc.) and I have really noticed a difference over the years from when I make that effort and when I don't. Apothecaries, naturopaths and doing research on one's own are good resources for learning more about that.
No need to be fearful--just use common sense and some protective measures.
Good luck in your restoration efforts!
Val