The asbestos is trapped in the vinyl so if he doesn't break it up too much
taking it out there isn't much danger. I know there has been a lot of hysteria
about asbestos but most of the people who were affected worked in a brake pad
plant, a shipyard or a mine.
It ain't plutonium.
Certainly your advice about the dust mask, or better a respirator and dust
suppression is a good idea but that is a good idea anytime you have a dirty
environment.