Seat-mounted side impact and
roof-rail airbags are not intended to
inflate in frontal impacts, near-frontal
impacts, rollovers, or rear impacts.
A seat-mounted side impact
airbag is intended to deploy on
the side of the vehicle that is struck.
A roof-rail 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 seat-mounted side impact and
roof-rail airbags, deployment is
determined by the location and
severity of the side impact.
What Makes an Airbag
Inflate?
In a deployment event, the sensing
system sends an electrical signal
triggering a release of gas from the
inflator. Gas from the inflator fills the
airbag causing the bag to break out
of the cover and deploy. The inflator,
the airbag, and related hardware are
all part of the airbag module.
Frontal airbag modules are located
inside the steering wheel and
instrument panel. For vehicles with
seat-mounted side impact airbags,
there are airbag modules in the side
of the front seatbacks closest to the
door. For vehicles with roof-rail
airbags, there are airbag modules in
the ceiling of the vehicle, near the
side windows that have occupant
seating positions.
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.
Airbags supplement the protection
provided by safety belts. Frontal
airbags distribute the force of the
impact more evenly over the
occupant’s upper body, stopping
the occupant more gradually.
Seat-mounted side impact and
roof-rail airbags distribute the force
of the impact more evenly over the
occupant’s upper body.
But airbags would not help in many
types of collisions, primarily because
the occupant’s motion is not toward
those airbags. See When Should
an Airbag Inflate? on page 1-27
for more information.
Airbags should never be regarded
as anything more than a supplement
to safety belts.
1-28 Seats and Restraints