Before fiberglass’ wide use in insulation projects, mineral wool was the way to go for insulators. Due to its low cost and fire-resistant properties, asbestos was sometimes stitched to the mineral wool. There were even a few instances where mineral wool got contaminated with asbestos particles when it was produced in a factory that used asbestos on a constant basis.
It was relatively easy for the asbestos particles to become airborne when the mineral wool got disturbed. This was the case when the insulator would apply or remove the asbestos mineral wool. You could have been exposed if: