How Do Airbags Work? A Look at the Tech Behind Your Safety

How Do Airbags Work? A Look at the Tech Behind Your Safety

Airbag Technology

One of the most common safety features that come standard with all vehicles is the airbag. It wasn’t until the late 90s that airbags became a requirement for all cars on driver and passenger sides by the National Highway Transportation Safety Administration (NHTSA), but its conception dates back to as early as the 1950s.

When most people think of airbags, they think of it as the bag that deploys to slow a passenger’s forward motion to prevent injuries from car crashes. Statistics show that airbags have indeed reduced the risk of death from frontal crashes by 30%, so in the same capacity as seat-belts, airbags have saved the lives of many who could have potentially lost their lives to fatal car accidents.

Because airbags have been around for so long and have become a car standard, have we taken them for granted? Are they the unsung heroes of car safety as we know it? Possibly. But unappreciated is something that airbags are not. If you know anything about the laws of motion, you’ll understand why. The laws of motion were a heavy influence in the creation of the airbag.

Laws of Motion and the Airbag

To fully understand the function and purpose of the airbag, you need to have an understanding of the laws of motion. The biggest thing to understand is that moving objects have momentum, and unless those objects are stopped by an outside force, those objects will continue to move at the speed and direction it’s currently going.

This law, in reference to cars, is that if these objects (cars/drivers) aren’t restrained, it’s just going to keep going at the same speed it’s currently going. The restraint is an airbag preventing a driver’s forward motion through the dash or windshield. The other restraint or stopping outside force could be a tree or another car stopping the moving car from continuing at its optimum momentum. It’s a combination of Newton’s first and third laws of motion.

In knowing how an airbag packs so much power, it makes you curious as to just what kind of technologies go into making the airbag what it is today. Well, for starters, it took lots of trial and error, but dedication over time helped the auto industry finally get it right.

Everything from crash sensors to chemical reactions during deployment, airbags have greatly contributed to the saved lives of people all over the world. Take a look at the technologies behind the airbag.

Technologies Behind the Airbag

Airbag Sensor

The airbag sensor is the device that tells the bag to inflate. Airbag inflation only happens when there is a collision impact where the force is greater than running into a brick wall at 10-15 mph. When a crash has occurred, there is a switch that is flipped and the airbag sensors receive that information from the accelerometer.

The entire process of airbag inflation to deflation takes a total of one-twenty-fifth of a second because that’s how long it can take to save a life. The airbag has to inflate fast enough to cover the distance between the driver and the steering wheel or dash, upon impact; Yet, it also has to deflate at the precise speed to evenly slow the passenger’s momentum to zero, rather than forcing the driver or passenger to come to an abrupt halt.

Precise timing is extremely important simply because despite the many lives airbags have saved, there have been fatalities caused by the airbag’s overly powerful deployment against the body. That reason alone is why you want to make sure you’re seated at least 10 inches away from the frontal airbag.

Airbag Deactivation Switches

Yes, airbags are a car safety standard now, and have been for quite some time. But due to the concern for people being injured due to overpowered airbags, the NHTSA issued a rule that allowed car manufacturers to install lower-powered airbags. Later, dealers were able to have on/off switches installed to have airbags completely deactivated.

According to, despite the many benefits airbags bring, you might need to deactivate the passenger bag for various reasons. If your car doesn’t come equipped with an on/off switch already installed, you’re going to have to contact the NHTSA and request for an airbag on/off switch. This may seem counterproductive to your safety when driving, but this may be one of the best ways to injury-proof your car.

Chemical Reactions

During the deployment of an airbag, there are a number of chemical reactions that take place. Sodium azide and potassium nitrate react to produce nitrogen gas. When the nitrogen gas is formed, the hot blasts of nitrogen inflate the airbag. This entire process happens in the inflation system.

Tantalum In Airbags

The element tantalum also plays a significant role in the deployment of airbags.

This particular metal is crucial to the survival of the inflation system. The extreme temperatures arising from the chemical reaction triggering airbag deployment are too great for many other metals. Because this metal is so strong and reliable, tantalum metal is critical to the manufacturing process.


Air Bag Checks

Not too many people realize it but you can actually check your airbag to make sure it’s in working condition without deploying it. As soon as you get in your car and turn the ignition, if you look at the dash, you’ll probably see a number of lights come on and then go out. One of those lights that will come on is your airbag or SRS light. It will typically come on for up to 10 seconds and then go out.

When that light comes on, that lets you know that your airbag system is in working condition and will deploy in the event you need it to. If the light doesn’t come on when you start your car or if it comes on while you’re driving, you need to take your car to get checked out as soon as you can. This can potentially put you at an even higher risk of severe injury due to a car accident.

Future of Airbags

As technology advances, so will the improvement of airbags to better protect passengers in cars. Everything from smaller devices to head airbags, the future is bright for enhanced airbag safety features. Let’s just hope that these advancements will be available to all cars, and not just certain makes and models.


Bryce Newell is an automotive enthusiast who loves to write about the latest news, products, and DIY projects. While Bryce is an amateur in the field, he is passionate about cars and has been since he spent weekends in the garage helping his dad rebuild a 68 Dodge Charger as a kid.

Leave a Reply

Your email address will not be published. Required fields are marked *