ALT-1 How Vehicle Airbags Work
Vehicle airbags work by decreasing the momentum of vehicle occupants during a car accident. They keep the driver and passengers from striking the vehicle interior and help to contain them within the vehicle as well. These are important aspects of surviving a car accident.
Vehicle airbag systems consist of three main components, all integral to their function. They are the bag, the sensor, and the inflation system. Let's take a closer look at these individual components:
1. The Bag
Airbags are constructed from a fine gauge of nylon and then folded into the steering wheel and dashboard. In some cases, they are also fitted into the door panels and/or roof rails above the doors. Cornstarch or talcum powder is generally used within the storage system for airbags to keep them flexible and stick-proof.
2. The Sensor
This is the mechanism that tells the airbag to inflate. It generally requires the equivalent force of running into a brick wall at 10 - 15 mph in order to trigger it. Sensors in newer airbag systems can determine whether or not there is a person in the front passenger seat and whether or not the passenger weighs enough for the bag to be safely deployed.
3. The Inflation System
The inflation system of a vehicle airbag consists of a solid propellant (normally Sodium Azide) that is ignited by electrical current. The burning of this propellant quickly creates a large amount of nitrogen gas which inflates the airbag at a speed of roughly 200 - 300 mph. After inflation occurs, this gas is immediately dispersed through tiny holes in the airbag and the airbag deflates. The entire process takes about 1/25 of a second.
Airbags were originally designed to be used as a seatbelt replacement system and were installed in some vehicles as early as 1971. They didn't come into widespread use though until the late 1980s, and it wasn't until the mid-1990s that at least two airbags were standard in most cars.
Modern vehicle airbag systems are much safer than those used in the 80s and 90s, and now do more than just protect passengers from front-impact collisions. Current systems protect passengers from side-impact collisions, and some will help cushion and restrain the driver and passengers if the vehicle should roll over.
No longer marketed to replace seatbelts, it is now understood that airbags work in tandem with seatbelts to keep drivers and passengers upright and inside a car during a collision. Hopefully, you will never be in a serious car accident but if you are, be glad that vehicle airbags are required by law in all new cars sold in the United States.
