The windshield in an American  automotive vehicle is a regulated safety device as the same priority level of that of the seat belt  , the FMVSS (Federal Motor Vehicle Safety Standards) states that the windshield needs to protect occupants by so many PSI with the bonding of automotive urethane around the complete perimeter of the windshield glass to support occupants coming toward it in the case of a collision . Also the windshield is one of the main contributors in the support of the front framing of the  A -pillars of an auto motive vehicle in the case of a roll over.