If broken, laminated glass in the side windows of vehicles reduces the potential injury to passengers from flying pieces of glass. Testing by the National Highway Traffic Safety Administration (NHTSA) has shown that vehicles equipped with both side laminated glass and side curtain air bags provide better occupant retention during vehicle rollover than vehicles equipped with air bags alone.

NHTSA estimates that up to 1,300 lives could be saved each year if all vehicles were equipped with EPG.