How Do Airbags Work?

a guide on airbag deployment

Like the fire extinguisher gathering dust under your sink and the smoke alarms that only remind us they exist when the batteries run low (or we burn dinner), cars come with safety features we barely think about. We hear all about seatbelt safety and using blinkers, but airbags? Not so much. We know they’re there and hope they never have to work. But, when they do, they can save our lives.

So, how do airbags work? This life-saving tech isn’t just a balloon popping out of your dashboard. It’s a complex system that mixes physics, chemistry, and electronics to protect you in a crash. Seat belts help too, but airbags are crucial for car safety, designed to reduce injuries and save lives.

In this blog post, the team at Mizzoni’s Auto Body invites you to dive into the world of airbags— including their history, the science behind them, and the different types you can find. Whether you’re a car enthusiast or just curious, understanding how airbags work can make you appreciate this essential safety feature even more. So buckle up and let’s uncover the mysteries of airbags.

The Evolution of Safety

Airbags are safety features designed to inflate quickly during a collision, cushioning passengers and reducing injury risks. They’ve been around longer than you might think!


Airbags have evolved from a novel idea to a crucial safety component in modern cars. John W. Hetrick first patented the airbag in 1951, imagining it as a soft shield during impacts. The concept took off in the late 1960s when Japanese engineer Yasuzaburou Kobori added a chemical explosive for rapid inflation.


A major breakthrough came in 1968 with Allen Breed’s electromechanical airbag system. His design used sensors to detect collisions and deploy airbags in milliseconds, setting the stage for today’s airbag technology.


As technology advanced, the basic airbag system grew to include various types, like front, side, curtain, and knee airbags, offering comprehensive protection from different angles. Nowadays, airbags are a standard feature in vehicles, symbolizing their journey from a simple idea to a sophisticated, life-saving device.

Have You Been in a Car Accident?

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A Step-By-Step Breakdown

An airbag system is more than just a bag. It has sensors, an inflation mechanism, and the airbag itself, made from flexible fabric. Sensors are the operation’s brains, detecting sudden deceleration during a crash. Here’s the whole process:

The Collision

It starts with a collision. Your car’s sensors are always on alert for sudden stops, crashes, or impacts. These sensors act like the car’s nervous system, sending instant messages when they sense trouble.

The Signal

When a collision is detected, these sensors send a signal to the airbag’s control unit, which decides if the impact is severe enough to deploy the airbags. This decision happens in milliseconds, faster than you can say “airbag.”

The Chemical Reaction

Once the green light is given, an igniter triggers a chemical reaction inside the inflator. Typically, sodium azide reacts with potassium nitrate, producing nitrogen gas. This rapid gas production inflates the airbag.

The Inflation

The gas fills the airbag, making it burst through the cover on your steering wheel, dashboard, or side panel, fully inflating in about 20 to 30 milliseconds—quicker than you can blink. The airbag creates a soft barrier between you and parts of the car, absorbing and spreading out the force of the impact.

The Deflation

But the airbag’s job isn’t done. After inflating, it immediately starts deflating. This isn’t a flaw; it’s intentional. By deflating quickly, it absorbs the crash’s energy, softening the impact. Plus, it ensures you aren’t trapped against the steering wheel or dashboard by the airbag itself.

A Look at Different Types of Airbags

While front airbags get most of the attention, they aren’t alone. Today’s cars may have several types of airbags, designed to protect almost every part of you.
  • Front Airbags:

    The MVPs protecting you in most front and rear collisions. These are found in the steering wheel and dashboard.
  • Side Airbags:

    Deploy from the sides of the seat or door, protecting you during side impacts.
  • Side Curtain Airbags:

    Drop down from above the windows, shielding your head from the car’s side or flying debris.
  • Knee Airbags:

    Protect your lower limbs.
  • Seat Belt Airbags:

    A newer addition, spreading out the seatbelt’s force to reduce pressure on your chest.

Airbag system issues?

Don't worry, Mizzoni's Auto Body has your back. Our team is specialized in handling all airbag systems, modules, circuits, and all surrounding components. Reach out today - we will be happy to help!

For the Science Enthusiasts

When a car suddenly stops in a crash, passengers keep moving forward due to inertia. Airbags help slow down passengers more gradually, reducing the force on their bodies. Sensors measure the crash’s speed and force to trigger airbags if deceleration exceeds a preset threshold.

Airbag Inflation

Upon activation, an igniter starts a chemical reaction, often involving sodium azide (NaN3). The heat causes sodium azide to decompose explosively into nitrogen gas, shown in the equation 2NaN3 → 2Na + 3N2. Just 130 grams of sodium azide can produce 67 liters of nitrogen gas, enough to inflate a standard airbag.

Dangers of Sodium Metal

But what about the sodium? Sodium is a reactive metal that can quickly react with water—not something you want near your eyes, nose, or mouth during a crash. That’s why airbags also have chemicals that react with sodium to reduce toxicity.

Airbags Save Lives

The main goal of the airbag isn’t just to provide a soft cushion but to extend the time over which the head and upper body decelerate, spreading the forces over a larger area of the body. This helps prevent severe injuries typical in high-speed impacts.

Before and After a Wreck

With airbags, a little maintenance goes a long way. Always watch for your airbag indicator light on the dashboard. If it’s lit, something might be up with your airbag system, and it’s time for a visit to Mizzoni’s Auto Body.

While airbags are great at preventing serious injury they work best with seatbelts. So buckle up! It’s the ultimate safety duo.

If you’re in a wreck, your car may need some specialist TLC. You want a mechanic you know you can trust, who will work closely with your insurance to ensure you get the most coverage from your policy for any repairs, including any auto glass that was cracked or busted on impact.

The End of the Road

There you have it, the mystery of airbags revealed. From smart sensors detecting crashes to rapid chemical reactions inflating lifesavers in milliseconds, it’s a marvel of modern engineering and a crucial part of vehicle safety. While we at Mizzoni’s Auto Body love the science and mechanics behind these devices, what truly excites us is their role in protecting lives.

So, the next time you’re out driving, remember the silent guardians tucked neatly inside your car, ready to spring into action.

Mizzoni's Auto Body Location

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