GMC 2007 Acadia - Manual (Page 83)

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.
Rollover capable roof-rail airbags are designed to
help contain the head and chest of occupants
in the outboard seating positions in the first,
second, and third rows. The rollover capable
roof-rail airbags are designed to help reduce the
risk of full or partial ejection in rollover events,
although no system can prevent all such ejections.
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 81 for more information.
Airbags should never be regarded as anything
more than a supplement to safety belts.
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