How Does An Airbag Restrain; What Makes An Airbag Inflate - GMC 2005 Sierra 1500 Pickup Owner's Manual

Single Stage Airbags
If your vehicle has frontal airbags with single stage
deployment and your vehicle goes straight into a wall
that does not move or deform, the threshold level
is about 13 to 16 mph (20 to 25 km/h). (The threshold
level can vary, however, with specific vehicle design, so
that it can be somewhat above or below this range.)
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. Airbags supplement 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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