What Is An AirBag in a car?

Airbag Construction & Working

Airbags: How do they work?

An airbag is a pillow-like safety device that inflates during the events of a frontal crash of an automobile. The purpose of employing the air-bag is to provide a cushion for the occupants’ bodies. Thus, it prevents their direct collision with the inner objects such as the steering wheel or dashboard. Therefore, it is one of a modern-day car’s most vital safety features.

Construction of Airbag
The above diagram shows the construction details of an Airbag system.

There are three main components of the Air-bag system. It consists of an inflatable bag, an impact sensor, and an inflation system. Besides, they work with each other to inflate the bag. Thus, it protects the occupants. So, let’s look at them.


  1. Bag- Manufacturers make it of thin nylon fabric. Then, they fit it at the desired position inside the steering wheel by folding it.
  2. Sensor- The function of a sensor is to send the inflation signal to the airbag in a crash situation.
  3. Inflation system- This system performs the actual task of inflation of the bag. Upon receipt of the signal from the sensor, it carries out a chemical reaction between Sodium Azide (NaN3) and Potassium Nitrate (KNO3). As a result, it generates nitrogen. The tremendous pressure that the nitrogen generates causes the bag to inflate.
Operation of Airbag

However, the air-bag acts as a cushion. It prevents fatal injuries to the head of the occupants and thereby saves lives. Once the occupant’s body touches the air-bag, the gas in the bag starts dispersing out, and soon the bag deflates completely. The whole process described above completes in less than one twenty-fifth of a second.

Furthermore, the initial concept of air-bag was confined only to the driver and passenger airbags. However, modern vehicles have multiple air-bags such as the side, curtain, knee air-bags, etc.

Various airbags in a car
Figure 3- Various airbags in a car

Various studies indicate that Air-bags effectively reduce the death rate during fatal accidents.

For more information on Air-bag, please click here.

Watch the Airbag in action:

Home » Technical Anatomy » What Is An AirBag in a car?
CarBike Tech Avatar
CarBikeTech is a technical blog in the automobile field. It regularly publishes specific technical articles on automotive technology.