Knowing that Asbestos now banned in many jurisdictions.

I need to put a heat shield above my wood stove flue because where it
enters the masonry it is only 14 inches below the floor joists above, not
the required 18 inches. Shield will be fastened to and spaced about one inch
below the ceiling joists meeting Fire Dept. inspection and insurance
requirements.

Happen to have a suitable piece quarter inch asbestos sheet which needs
trimming. The cutting length will be about 30 inches. Also will drill four
or six holes. Probably do this by hand rather than power tools to avoid
cracking the sheet and/or blowing dust around.

Intend to cut outside with asbestos soaking wet, wearing a mask. And will
carefully wipe up and bury any wet dust/residue underground under trees.

Any comments on this please.

Or maybe should I just fashion a piece of sheet metal for a heat shield?

Later if/when I 'finish' the existing vertical poured concrete wall behind
the wood stove, a similar spacing situation will occur and a heat shield may
be required behind the burning unit itself.