I am just being curious. I went to buy a car and the dealer was praising the workability of the car. And he was always reminding me of the presence of "Air Bags"; being one of the reasons, among others, for the slight increment in the price of the car.

Could nairalanders enlighten me on this gadget? Pls dont castigate me!!!!!!

haha. . .because of Airbags, price of car don skyrocket. Airbags are safety devices and these days, almost every vehicle is equipped with airbags. They are meant to complement your seatbelt in the event of a collision, hence giving you a chance for survival.

Anyway, read below from wikipedia:

An air bag, A.K.A. a Supplementary Restraint System (SRS), an Air Cushion Restraint System (ACRS), or the Supplemental Inflatable Restraint (SIR) (reflecting the air bag system's intended role as a supplement to conventional restraints such as seatbelts) is a flexible membrane or envelope. Air bags are most commonly used for cushioning, in particular for rapid inflation in the case of an automobile collision. Air bags are designed to complement conventional restraints such as seatbelts and seatbelt pre-tentioners, not replace them. The number of lives saved by airbags is hard to pin down. One study, cited below, puts the number at just under 400 per year (6,000 total), and another study indicates that air bags reduce fatalities by 8% when seatbelts are worn. Airbags also greatly increase the efficiency of seat-belts, in some cases up to 50%.

How air bags work
The design is conceptually simple - accelerometers trigger the ignition of a gas generator propellant to inflate a nylon fabric bag very rapidly, which reduces the deceleration experienced by the passenger as they come to a stop in the crash. The bag has small vent holes to allow the propellant gas to be (relatively) slowly expelled from the bag as the occupant pushes against it.

Many vehicles have several accelerometers and gyroscopes to help sense various impacts and other crash events. The different signals from these sensors are fed into a microprocessor which determines the angle of impact and the severity of the crash. Depending on the result of these calculations, the microprocessor will deploy various restraint devices such as seat belt pre-tensioners and/or air bags. Each restraint device is typically activated with one or more pyrotechnic devices commonly called an initiator or squib. The squib activates with a current pulse between 1 to 3 amperes in less than 2 milliseconds. The squib has a fuse-like conductor inside that heats the pyrotechnic material tightly packed around the conductor. When the conductor becomes hot enough, it ignites the pyrotechnic material which in turn generates hot gas. In a seat belt pre-tensioner, this hot gas is used to drive a piston that pulls the slack out of the seat belt. In an air bag, the hot gas from the squib is used to ignite solid propellent inside the air bag inflator. The burning propellent generates inert gas which rapidly inflates the air bag in approximately 20 to 30 milliseconds. An air bag must inflate quickly in order to be fully inflated by the time the forward-traveling occupant reaches its outer surface. Typically, the decision to deploy an airbag in a frontal crash is made within 15 to 30 milliseconds after the onset of the crash, and both the driver and passenger airbags are fully inflated within approximately 60-80 milliseconds after the first moment of vehicle contact. If an air bag deploys too late or too slowly, the risk of occupant injury from contact with the inflating air bag may increase. Since more distance typically exists between the passenger the instrument panel, the passenger air bag is larger and requires more gas to fill it.

During the crash, the force of the occupant going forward (toward the point of impact) forces the gas out of the air bag through its vent holes, thereby causing it to deflate. It is the deflation of the air bag that provides the cushioning effect to the occupants as they continue to be thrown forward toward the point of impact. The air bag's volume and the size of the vents in the bag are tailored to each vehicle type to dissipate the occupant's energy over time and distribute the deceleration forces across a larger portion of the occupant's body (compared to a seat belt alone).

Front air bags are not designed to deploy in side impacts, rear impacts or rollover crashes.[citation needed] Since air bags deploy only once and deflate quickly after the initial impact, they will not be beneficial during a subsequent collision. Safety belts help reduce the risk of injury in many types of crashes. They help to properly position occupants to maximize the air bag's benefits and they help restrain occupants during the initial and any following collisions.

In vehicles equipped with a rollover sensing system, accelerometers and gyroscopes are used to sense the onset of a rollover event. If a rollover event is determined to be imminent, side-curtain air bags are deployed to help protect the occupant from contact with the side of the vehicle interior, and also to help prevent occupant ejection as the vehicle rolls over.

http://en.wikipedia.org/wiki/Airbag