I work in QC at a steel mill. We have a policy on guns but not knives. The policy states that you shouldn't have a firearm on company property. But when hunting season rolls around, just about every truck in the parking lot has a rifle in the seat of rear window and no one says anything about it. As far as knives go, they don't care if you carry one but if you cut yourself with your personal knife and not a company issued one there could be some trouble.