How Does an Airbag Restrain?

In moderate to severe frontal or near-frontal crashes, even belted occupants can contact the steering wheel or instrument panel. In moderate to severe side crashes, even belted occupants can contact the interior of the vehicle.

Airbags supplement the protection provided by the seat belts by distributing the force of the impact more evenly over the occupant's body.

Roof-rail airbags that deploy from the roof rails are designed to help reduce head and chest injuries to occupants in the outboard seating positions in the first and second rows. Rollover-sensing roof-rail airbags are designed to help reduce the risk of complete or partial ejection in rollover events, although no system can prevent all such ejections.

However, airbags would not help in many types of crashes, primarily because the occupant is not moving toward the airbags. See When Should an Airbag Deploy?.

Airbags should never be thought of as anything more than a supplement to seat belts.