Subaru IMPREZA 2002 Owner's Manual page 77

Seat, seatbelt and SRS airbags
deploys between the occupant and the door panel
and supplements the seatbelt by reducing the im-
pact on the occupant's chest.
1-54
B Operation
The SRS side airbag can function only when the
ignition switch is in the " ON" position.
The driver's and front passenger's SRS side airbags
deploy independently of each other since each has
its own impact sensor. Also, the SRS side airbag de-
ploys independently of the frontal airbags in the
steering wheel and instrument panel.
An impact sensor is incorporated into each of the
vehicle's center pillars. If either sensor detects a
certain predetermined amount of force during a side
impact collision, the control module sends a signal
to the side airbag module on the impacted side of
the vehicle, instructing it to inflate the SRS side air-
bag. Then the side airbag module produces gas,
which instantly inflates the SRS side airbag. After
the deployment, the SRS side airbag immediately
starts to deflate. The time required from detecting
impact to deflating of the SRS side airbag after de-
ployment is shorter than the blink of an eye.