FORD 2009 Edge v.3 - Manual (Page 151)

How does the safety belt pretensioner and airbag supplemental
restraint system work?
The safety belt pretensioner and
airbag SRS are designed to activate
when the vehicle sustains
longitudinal deceleration sufficient
to cause the sensors to close an
electrical circuit that initiates
pretensioner activation and airbag
inflation.
The fact that the airbags did not
activate in a collision does not mean
that something is wrong with the
system. Rather, it means the forces were not of the type sufficient to
cause activation. Front airbags are designed to activate in frontal and
near-frontal collisions, not rollover, side-impact, or rear-impacts unless
the collision causes sufficient longitudinal deceleration.
The airbags inflate and deflate
rapidly upon activation. After airbag
deployment, it is normal to notice a
smoke-like, powdery residue or
smell the burnt propellant. This may
consist of cornstarch, talcum
powder (to lubricate the bag) or
sodium compounds (e.g., baking
soda) that result from the
combustion process that inflates the
airbag. Small amounts of sodium
hydroxide may be present which
may irritate the skin and eyes, but
none of the residue is toxic.
While the system is designed to help
reduce serious injuries, contact with
a deploying airbag may also cause abrasions, swelling or temporary
hearing loss. Because airbags must inflate rapidly and with considerable
force, there is the risk of death or serious injuries such as fractures,
facial and eye injuries or internal injuries, particularly to occupants who
are not properly restrained or are otherwise out of position at the time
of airbag deployment. Thus, it is extremely important that occupants be
properly restrained as far away from the airbag module as possible while
maintaining vehicle control.
Seating and Safety Restraints
151
2009 Edge (edg)
Owners Guide, 3rd Printing
USA (fus)