Airbags - How do airbags work?

air bags

Air bags

Airbags save lives, but can also be dangerous because they open with great force and can cause injury. Today, almost every car has them, but many misconceptions still exist.

The idea of ​​airbags emerged in World War II and was developed and promoted by various engineers to appear in series vehicles in the XNUMXs, but it was not until the XNUMXs that they became widely used.

The basic idea is simple - sensors in the event of an accident send signals to a central unit (computer), which processes them and, if it deems it necessary to activate, sends a signal to the airbag to open.


Once upon a time, only one sensor was used, and today we have an abundance of them: accelerometers, impact sensors, door pressure sensors, passenger presence sensors, passenger weight sensors, rollover sensors…

The computer also monitors the speed of the vehicle, and depending on age / type / model / equipment, receives information from systems such as ABS i ESP (Electronic Stability Control) and other advanced security systems.


The airbag is activated by pyrotechnics - popularly speaking, with a small explosion. Electrically ignites a mixture of several substances that, during combustion, release nitrogen gas, filling the pillow in as little as 20-30 milliseconds.

The airbag itself is made of synthetic composite canvas, with vents for gas venting, to give a cushioning effect when in contact with a passenger. Without these openings, passengers would have felt like they had hit their head on the wall.

Activation "decision"

It is often the case that the car suffers significant damage in the event of an accident without the airbags opening. It should be borne in mind that sometimes it is better not to activate, regardless of the fact that you are moving at high speed.

For example, if you hit a vehicle with a sudden hitch in front of you at 80 km / h, you start braking and rolling the steering wheel at the same time to avoid it, hit your front right corner with its rear left, you will continue to move and have a chance to safely stop if you keep your cool and stay on the tarmac (and no one comes in the opposite direction).

If an airbag or more airbags open up in such a situation, the consequences could be serious, as you would probably lose control of the vehicle. The material damage will be great, but the fact is that there was no need to open the pillow.

It is also possible for the car to hit a pole, which would penetrate the engine compartment but would not activate the cushion, because the computer estimated that the deceleration force was not of the required intensity.

Simply, the airbag is there to protect you in situations where a seat belt is judged to be insufficient.

air bags

Air bags

Will the airbag activate if the belt is not tied?

Yes he does. The airbag will deploy even if the seat belt is not fastened. Entire conspiracy theories are being developed on this topic, which became especially effective when the singer Tose Proeski was killed.

Experts, manufacturers and engineers claim that the airbags are activated regardless of whether the driver and passengers are tied. Despite this, many drivers are still convinced of the opposite.

Can they hurt?

Because the airbags open at high speed, injury can occur, especially if you are not tied up, not sitting properly or sitting too close. Especially dangerous is the position with the legs on the front console, which is adored by the members of the nicer sex. If the pillow opens then, injuries to the legs, hips and spine can be very dangerous.

It is also extremely dangerous if e.g. the mother holds the child in her lap in the passenger seat.

The ability to activate the airbag is another reason to hold the steering wheel properly. If you hold the steering wheel with one hand on the so-called at 12 o'clock or some other "handgun" way, there is a good chance that you will suffer injuries when the airbag crashes.

Owing to the forceful opening, there is a possibility of formation of scabs on the face or hands, hearing damage (explosion causes noise up to 175 dB), injuries to the eye, nose, jaw, fingers or cervical vertebrae. As the pillow inflates with hot gas released by a chemical reaction, burns to the face or hands have also been reported.


There should be a minimum of 25 cm for the driver and 35 cm for the front passenger between the body and the point of departure. Do not hold the steering wheel by the arms or the top, but by the rim on the so-called. positions 10 and 14 hours or lower.

In critical situations do not use the siren - then a severe break in the arm can easily occur if a collision occurs. Passengers often have the habit of reflexively stretching their arms toward the front console in dangerous situations to stay on - when the airbag is activated, the consequences can be more than serious.

They are not a replacement for the belt

You will find a mark on the airbags SRS - "Supplemental Restraint System", which means that it is a system that serves as an aid to the seat belt, and not as its replacement. If you are not tied, there is a possibility of crawling under the airbag and thus getting serious leg injuries.

How Many Airbags Can There Be In Your Car?

Luxury cars can have over 10 airbags. Two front, two side, two air curtains (which also cover the rear bench), for the knees, for the hips of the driver and front passenger, one central on the rear bench (

air bags

Air bags

Can the airbag break down?

Of course, like everything else. Generally, the problem is very easily solved (eg passenger presence sensor malfunction or corroded contacts), but be sure to visit a service if the light comes on.

Is everyone on the number?

Because replacing them is very expensive, the owner of a wrecked car often only repairs where the airbag came from without installing a new one. This can be very dangerous when traveling later and unfortunately, there are various ways to fool and adjust the system so that the faulty airbag warning light on the instrument panel does not illuminate. Otherwise, when everything is right, the light should come on when making contact and turn off after a few seconds.


The smoke that occurs after the airbag is opened comes from a special powder that serves as a lubricant - reducing injuries due to the friction of the airbag and the passenger's skin. This powder is harmless.


There is no doubt about their usefulness. Many times they have played a key role in saving the lives of passengers in the car and represent one of the most advanced steps so far in passenger safety.

That is why it is very important to take care of their correctness. When buying a used car, you should check their condition, and when buying a new car of a smaller category, in the so-called "clot variant", be sure to allocate additional funds to protect all future passengers with pillows.

Author: Dragan Romcevic
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