On construction clean-up jobs if there is any glass that is next to the ground where they will pour cement, I tell the general contractor the problems that might result when they pour cement on the glass and ask them to cover up the glass. If they balk or don't seem responsive I'll tape some plastic sheeting over myself. Same goes for any welding work to be done adjacent glass. If you can catch these areas ahead of time, everybody has a lot less grief down the road.