What Makes An Airbag Inflate; How Does An Airbag Restrain - Chevrolet Silverado Classic 2007 Owner's Manual

Dual Stage Airbags
If your vehicle has frontal airbags with dual stage
deployment, the amount of restraint will adjust
according to crash severity. Your vehicle has
electronic frontal sensors which help the sensing
system distinguish between a moderate and a
more severe frontal impact. For moderate frontal
impacts, these airbags inflate at a level less
than full deployment. For more severe frontal
impacts, full deployment occurs. If the front of
your vehicle goes straight into a wall that does
not move or deform, the threshold level for
the reduced deployment is about 10 to 16 mph
(16 to 25 km/h), and the threshold level for
a full deployment is about 20 to 30 mph
(32 to 48 km/h). The threshold level can vary,
however, with specific vehicle design, so that
it can be somewhat above or below this range.
Vehicle's with dual stage airbags also have
special sensors which enable the sensing system
to monitor the position of both the driver and
passenger front seats. The seat position sensor
provides information which is used to determine
if the airbags should deploy at a reduced level
or at full deployment.
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 and in the instrument panel in front of the
right front passenger.

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.
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 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 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.
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