Good luck with that. We got nails in tires a couple of times when a Metro line was going in along one of our commuting routes.

Really, all it takes for one carpenter to bend a nail, pull it out, and toss it over his shoulder.

My neighbor had work done on their roof, the company doing the work ran a rolling magnet over my property (driveway) along where the work was being done and the neighbor's property with a rolling magnet. It should be SOP to do this regularly whenever construction is done.