original antique american depression era single-sided brightly colored "special instructions" safety first sign fabricated by or for the standard oil company of indiana. the stamped metal wall mount sign would likely have been posted in or around a refinery, adjoining factory or perhaps a train yard. the thin metal sign contains several safety tips to abide by while working within that environment. measures 11 1/2 x 8 1/2 inches. great condition, considering age.