The task of the airbags in case of accident is to gently reduce the speed of the driver and passengers, soften their hit by the wheel, parts of the body and window. The airbags work on the principle of pyrotechnic composition: at the moment of collision the crystalline substance–sodium azide (NaN3) ignites and quickly degrades into nitrogen and sodium, filling the elastic coating of the airbag with the gas. The mechanism launching the airbags depends on the speed of car and rate of its deceleration, the use of seat belts, the weight and location of passenger and the presence of a baby seat.
Depending on the location and the focus of action, the airbags are divided into the following groups: frontal, central, lateral (head curtain airbag), head and knee.
There are two frontal airbags. One of them is built into the wheel and intended to provide the driver’s safety. The second one is situated on the upper right side of the front panel. Its purpose is to protect the front passenger from the hit.
The central airbag is located in the armrest of the front seat, in the center of the back of the rear seat. Its task is to reduce the extent of damage in the side impacts.
The lateral airbags are situated in the back of the front seat or on the rear seats.