Not many individuals realise that the design of the air bag – a soft buffer to land against in a crash – has been around for over sixty years. The very first patent on an inflatable crash-landing device for airplanes was submitted during World War Two. In the 80s, the very first commercial airbags appeared in automobiles.

Up to now, stats indicate that airbags reduce the risk of death in a direct head-on crash by around 30%. Nowadays there are also seat mounted and door-mounted side air bags. Actually, some cars go way further than just having dual air bags, and instead have 6 to 8 airbags.

The job of an air bag is to slow down the driver’s progressive movement as evenly as possible in just a split second. There are 3 components to an airbag that help achieve this task:

• The airbag itself is composed of a thin, nylon that’s folded into the steering wheel or dashboard and, these days, the door or seat
• The detector is the device that orders the airbag to balloon. Expansion takes place when there’s a crash force equating to motoring into a wall at around 15 miles per hour. A mechanical switch is thrown when there’s a mass shift that closes an electrical contact, informing the detectors that a crash has happened. The detectors get data from an accelerometer built into a microchip
• The bag’s expansion system fuses sodium azide (NaN3) with potassium nitrate (KNO3) to produce nitrogen gas. Hot gusts of the gas expand the airbag

Because of the superfast deployment of an air bag, it’s essential the passenger and driver sit in an upright position giving a good space between the steering wheel / dashboard and their face – this allows time for the bag to inflate while the passenger/driver are being thrust forward by the impact of the accident.

This entry was posted on Sunday, November 1st, 2009 at 11:38 pm and is filed under Cars + Rides. You can follow any responses to this entry through the RSS 2.0 feed. Both comments and pings are currently closed.