In the past 100 years cars and trucks have come a long way in their development. The first vehicles could barely do 25 miles per hour, and there really wasnt a need for safety features like seat belts. As the engine became more powerful, the seat belt became standard in the car. As technology progressed, drivers side airbags were added. Now we find airbags all over the car helping to cushion the impact that occupants may feel if they are involved in a car crash.
The Sensor
Automotive engineers have developed the airbags to go off at precisely the right time during a crash. By smashing hundreds of their vehicles into brick walls, they know exactly how the impact will occur, and at which moment the airbag must deploy in order to help protect those in the car. It is all done through sensors.
These sensors detect impact and movement. When the car suddenly stops due to a massive impact on the front end the sensor is designed to send a rapid electrical signal to the airbag. This tells the airbag to deploy.
The Inflator
The airbag is made up of a few different parts. The primary components are the inflator, the airbag itself, and the housing compartment. When the inflator receives the signal from the sensor, it fills the airbag within a split second. This is done because there is compressed gas inside. The sudden release of the gas forces the airbag open rapidly to absorb the impact. But it doesnt just stay inflated. Within a split second the airbag is deployed, inflated, and deflated.
Problems with Airbags
With so many different parts, and working components, there is always the chance that something will go wrong with the airbag. This was seen with Takata airbags over the last decade and a half; they were known to explode open with so much force that the housing compartment literally exploded and has injured and killed dozens of people. Fortunately these problems are relatively rare.
Airbags have saved thousands of lives throughout their history. The few that have been hurt or killed by them are nothing to worry about, and you should rest assured that unless your vehicle is on the recall list, your airbag ought to deploy without issues. Not that you would ever want to find out if it does.