Is that idiocy even legal? We had the mirror case at a previous workplace once, when an arts class drew artsy warning signs, but then they hung them up in the S

Is that idiocy even legal? We had the mirror case at a previous workplace once, when an arts class drew artsy warning signs, but then they hung them up in the Science Building to serve as genuine warning signs. Several "Emergency Exit" signs went about the doors, there was a neat "Inflammable" sign on the steel cabinet for solvents & so on.