Side/window Air Bag problems of the 1999 Hyundai Tiburon

My son was driving on a highway entering a freeway on an on ramp when his airbag "exploded" for no reason. There was nothing on the road he was simply driving along on the highway. The air bag exploded which resulted in my son hitting a wall barrier on the freeway. At the point of impact his passenger side air bag deployed. Since it was late at night we towed the car to a dealer where it currently is. My son has complained about pain in his chest and is shook up emotionally but thank god that it didn't result in much worse.