The threshold level can vary with specific vehicle
design. A driver’s side impact airbag 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
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
the angle of the impact and how quickly the vehicle
slows down in frontal and near-frontal impacts. 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. 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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