{"id":4358,"date":"2020-04-24T19:00:00","date_gmt":"2020-04-24T19:00:00","guid":{"rendered":"https:\/\/carexamer.com\/blog\/?p=4358"},"modified":"2026-02-26T23:26:46","modified_gmt":"2026-02-26T23:26:46","slug":"the-miracle-of-airbags-how-they-work","status":"publish","type":"post","link":"https:\/\/carexamer.com\/blog\/the-miracle-of-airbags-how-they-work\/","title":{"rendered":"The Miracle of Airbags & How They Work"},"content":{"rendered":"\n

<\/path><\/svg><\/span><\/span>Estimated reading time: <\/span>6<\/span> minutes<\/span><\/p>\n\n\n\n

When it comes to safety in your car and on the road, airbags and how they work is one of the most miraculous inventions ever made. It\u2019s one of the most revolutionary safety inventions since Volvo released the seatbelt patent and made them accessible to everyone, and they save countless lives on a daily basis. They really don\u2019t get the recognition they deserve. What\u2019s even more amazing in this situation than what the airbag does, however, is how it actually does it and how airbags actually work both inside and out, as well as why it is so vital to the preservation of life and making us all safer on the road. <\/p>\n\n\n\n

To really develop that understanding to where it needs to\nbe, that means we need to look at a few different things.<\/p>\n\n\n\n

Crash Physics<\/h2>\n\n\n\n

First of all, let\u2019s look at what a car crash really is and what\u2019s going on during it. When we\u2019re driving, we\u2019re moving a huge mass of metal (and people\/objects). To do that, we generate horsepower<\/a> from our engines to propel us forwards, at any speed, or velocity, that we like. <\/p>\n\n\n\n

When we force that speeding mass to stop, that energy transfers elsewhere, and causes a huge amount of damage in the process depending on what it takes to stop the car (faster + heavier means harder). That can come in one of two ways, too, and it matters much more than you might think.<\/p>\n\n\n\n

Example 1<\/h3>\n\n\n\n

One of the more obvious examples of a crash is a car hitting\ninto something stationary. Whether that is a tree, a wall, or even another car,\nthe car is being forced to stop immediately. All of the energy you had wrecks\nthe car and whatever you hit, and you\u2019re susceptible to the same thing even\ninside the car. You have the exact same force happening to your body too. The\nquicker the reaction takes place, the more rapid the energy transfer is and the\nmore damage is done too. That\u2019s what crumple zones are for, but they don\u2019t\nreplace airbags.<\/p>\n\n\n\n

Example 2<\/h3>\n\n\n\n

In the same sense, exactly the same reaction can happen even if you\u2019re going much slower, too. Not many people realise this, but the physics of a crash actually means you can make a crash much worse even when you\u2019re not going as fast as you could. For example, making your car too heavy is an easy way to do it, as it\u2019s much harder to stop that much momentum. Another is to hit something moving towards you, like another car doing the same speed. Two cars similar in weight hitting head on both at 40mph is very similar to hitting a wall or a tree at 80mph because there’s momentum from both ways creating a combined force. <\/p>\n\n\n\n

It\u2019s dangerous stuff, even when you don\u2019t know it. That\u2019s\nwhy airbags and understanding how they work is so essential.<\/p>\n\n\n\n

Why We Need Airbags<\/h2>\n\n\n\n

This just opens up more doors as to why we need these magical bags of safety. When all of this is going on and your car is being forced to stop, for whatever reason, your body is doing the same. You are inside a box going through this massive energy transfer and have your own going on too, from your own mass and speed. The difference, however, is that you’re stopped by your seatbelt, if you’re wearing one, as well as the rest of the car too. <\/p>\n\n\n\n

Whether your seatbelt stops you or not, you can still do a huge\namount of damage to yourself when you\u2019re crashing a car. That\u2019s because your\nhead and your neck aren\u2019t supported or fixed into place, and when you stop, you\nmove these forwards with a huge force. The result at best is a heavy and\nviolent jerk forwards, and then an even worse one going back. That’s what\nwhiplash is. You’re putting a huge strain on your back, neck and your head. If\nyou\u2019re not wearing the belt, you instead hurtle forwards and collide with your\nsteering wheel, dashboard or even a passenger seat in the back. Either way,\nit\u2019s a huge impact on your whole body.<\/p>\n\n\n\n

Airbags and how they are designed to work is a way to stop\nboth of these things from happening. The bag deploys to keep your head in place\nand take the force out of your personal reaction as it absorbs the blow.<\/p>\n\n\n\n

How does the Airbag work?<\/h2>\n\n\n\n

Let\u2019s move on to what we\u2019re really here for. How does the\nairbag work in all this? It\u2019s actually a double-edged sword in this respect, as\nthere are two parts to the airbag reaction. They both have an amazing effect to\nhelp keep you safe and save your life.<\/p>\n\n\n\n

Step 1- The Explosion and Inflation<\/h3>\n\n\n\n

Firstly, the bag has to fill up. That\u2019s how this whole\nsystem works, and it\u2019s the only thing that is going to absorb all of this force\nby supporting your head in the reaction. To do that, it\u2019s actually down to a\nchemical reaction.<\/p>\n\n\n\n

The bag collecting air would take much too long in a car crash,\nso instead, we use an explosion. A chemical explosive inside the airbag, and\nwhen you break unnaturally hard as is with a collision, the explosion releases\na huge burst of gas which causes the bag to inflate dramatically and rapidly.\nThis is what essentially hits you in the face and keeps you in pace with a soft\nblow.<\/p>\n\n\n\n

Step 2 \u2013 The Deflation on impact<\/h3>\n\n\n\n

After the bag has done its job and saved you from flying\nforwards, it also has to make sure it doesn\u2019t knock you back with even more\nforce than there was before. A reaction that fast could push you even harder\nthan you already could be after all. To do that, the bag has to minimise the\nblow as soon as you collide with it.<\/p>\n\n\n\n

To do that, the bag actually deflates almost as fast as it\ninflates. As soon as you impact with the bag, the gasses are pushed out of\nholes all around the bag to make it deflate. That prevents a bouncing effect of\nthe bag and means your neck doesn\u2019t slam you back into the seat. It\u2019s really an\nextremely intelligent invention.<\/p>\n\n\n\n

Conclusion<\/h2>\n\n\n\n

Ultimately, that\u2019s the whole thing. How airbags work is mostly through a crash, an explosion inflating the bag, and your impact causing it to deflate, preventing you from moving more than you should. It\u2019s one of many incredible safety features that your car has to protect you, like crumple zones to take away the force by prolonging the reaction and even the seatbelts stopping you hitting the dash. They all work together to protect you and your loved ones even without you knowing they exist.<\/p>\n\n\n\n

Cars are always going to be dangerous when crashes occur. There\u2019s no such thing as a safe crash when you\u2019re on the road, and all of the physics and precautions in the world can’t keep you safe. The best lifesaver you have when you’re driving is your concentration and ability to follow the rules of the road. It’s essential that you drive as well as you can, and do so safely, calmly, and minimise the risks you take. If things do ever go wrong, the equipment is there to help. Check the health of these safety features when you can and however you can, especially if you buy a new car, and always make sure your car is safe. When buying a used car you may save money, but it can also backfire \u2013\u00a0carry out car history check<\/a> to pick up any write off categorisation<\/strong>. Take your time and inspect everything, and when in doubt, get a professional\u00a0pre purchase inspection<\/a>.<\/p>\n\n\n\n

Stay safe, and happy driving!<\/p>\n\n\n\n