Air Bag Not Deploy problems of the 1999 Oldsmobile Alero

My son was driving down his 1999 Oldsmobile Alero at approximately 15-20 mph when he ran into the back of a parked older vehicle which had a steel bumper. My son's 1999 Oldsmobile Alero suffered major damage and my son hit his head on the steering wheel. The airbag did not deploy. Nothing has been done to correct the problem.

Air bag failed to deploy in front end collision. Car totaled.

While driving about 15 mph and applying the brakes, vehicle skidded and hit another vehicle at a frontal impact. Upon impact, driver's and passenger's airbags did not deploy which did not protect the occupants in this crash. Please provide further information.