What Makes An Airbag Inflate; How Does An Airbag Restrain - Buick 2005 Century Owner's Manual

A driver's side impact air bag is not designed to inflate in
frontal or near-frontal impacts, rollovers or rear impacts,
because inflation would not likely help the occupant.
In any particular crash, no one can say whether an air
bag should have inflated simply because of the damage
to a vehicle or because of what the repair costs were.
For frontal air bags, inflation is determined by the angle
of the impact and how quickly the vehicle slows down
in frontal and near-frontal impacts. For side impact
air bags, inflation is determined by the location
and severity of the impact.
What Makes an Airbag Inflate?
In an impact of sufficient severity, the airbag sensing
system detects that the vehicle is in a crash. For both
the frontal and side impact airbags, the sensing system
triggers a release of gas from the inflator, which
inflates the airbag. The inflator, airbag and related
hardware are all part of the airbag modules. Frontal
airbag modules are located inside the steering wheel
and instrument panel. For vehicles with a driver's
side impact airbag, the airbag modules are located in
the seatback closest to the driver's door.

How Does an Airbag Restrain?

In moderate to severe frontal or near frontal collisions,
even belted occupants can contact the steering wheel
or the instrument panel. In moderate to severe side
collisions, even belted occupants can contact the inside
of the vehicle. The airbag supplements the protection
provided by safety belts. Airbags distribute the force of
the impact more evenly over the occupant's upper
body, stopping the occupant more gradually. But the
frontal airbags would not help you in many types
of collisions, including rollovers, rear impacts, and many
side impacts, primarily because an occupant's motion
is not toward the airbag. A side impact airbag would not
help you in many types of collisions, including frontal
or near frontal collisions, rollovers, and rear impacts,
primarily because an occupant's motion is not toward
that airbag. Airbags should never be regarded as
anything more than a supplement to safety belts, and
then only in moderate to severe frontal or near-frontal
collisions for the driver's and right front passenger's
frontal airbags, and only in moderate to severe
side collisions for vehicles with a driver's side
impact airbag.
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