The side impact airbags are intended to inflate in
moderate to severe side crashes. A side impact airbag
will inflate if the crash severity is above the system’s
designed “threshold level.” 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 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. 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, instrument panel, the side
of the front seatbacks closest to the door and 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, 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.
1-56