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. In the case
of a “rollover capable” roof-mounted side impact airbag,
the sensing system detects that the vehicle is about to roll
over. 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
roof-mounted rollover airbags, the airbag modules,
the inflator and the airbags are located 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. Roof-mounted side impact
airbags would not help you in many types of collisions,
including many frontal or near frontal collisions, 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 or rollovers for the roof-mounted
side impact airbags.
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