What Makes An Airbag Inflate; How Does An Airbag Restrain - Chevrolet 2006 HHR Owner's Manual

The threshold level can vary with specific vehicle design.
Side impact airbags are not intended to inflate in frontal or
near-frontal impacts, rollovers or rear impacts. A side
impact airbag is intended to deploy on the side of the
vehicle that is struck.
In any particular crash, no one can say whether an
airbag should have inflated simply because of the
damage to a vehicle or because of what the repair costs
were. For frontal airbags, inflation is determined by
what the vehicle hits, the angle of the impact, and how
quickly the vehicle slows down. For side impact
airbags, 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. 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
inside the steering wheel and in the instrument panel
in front of the right front passenger. For vehicles
with side impact airbags, there are also airbag modules
in the ceiling of the vehicle, near the side windows.

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. Side impact airbags would not
help you in many types of collisions, including many
frontal or near frontal collisions, rollovers, and rear
impacts, primarily because an occupant's motion is
not toward those airbags. 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 side impact airbags.
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