Airbags explained: From deployment to protection

For years, cars have been equipped with airbags, working alongside safety features like seatbelts and ABS. Today, we delve into the world of "Airbags" to give you a comprehensive understanding of their function.

What are airbags? An airbag is an inflatable safety device made of stretchable nylon fabric, designed to protect car passengers during collisions by rapidly inflating upon impact, preventing them from hitting the vehicle's interior and supplementing seatbelt safety.

Automotive airbags are typically positioned in the steering wheel, dashboard, and side panels. Folded and placed in strategic points within the car, airbags inflate upon receiving signals from car sensors. The airbag system relies on sensors positioned throughout the vehicle, mainly at the front and sides, to detect rapid changes in acceleration and force typical of a collision. When these sensors detect an impact force exceeding a predetermined threshold, they send an electrical signal to the airbag control unit (ACU). The ACU then activates the inflator for the specific airbag(s) involved in the crash. The inflator contains a chemical compound, such as sodium azide, which decomposes rapidly upon receiving the electrical signal. This decomposition generates a large amount of nitrogen gas at high pressure, inflating the nylon airbag within milliseconds. The inflated airbag acts as a cushion between the occupant and the car's interior, absorbing impact force and reducing the risk of injuries from contact with hard surfaces. After the initial impact force is absorbed, the airbag begins to deflate through vents in the fabric, allowing the occupant to move freely after the collision.

Various types of airbags serve distinct purposes in enhancing occupant safety during collisions:

Frontal airbags are the most common and are typically embedded in the steering column for the driver and the dashboard for the front passenger. They rapidly inflate during frontal collisions, creating a cushion between the occupant's head and chest and the car's interior, thereby reducing the risk of head trauma and internal bleeding.

Side airbags, available in seat-mounted and curtain variations, provide additional protection in side-impact collisions and rollovers. Seat-mounted side airbags shield the occupant's torso from impact with the door or intruding objects, while curtain airbags extend down from the headliner along the sides of the car, protecting the heads and necks of all occupants, including those in the back seat.

Knee airbags, located below the dashboard, deploy during frontal collisions to protect the driver's knees and legs from colliding with the lower part of the dashboard, reducing the risk of knee fractures and other leg injuries.

Additional airbag types include rear seat airbags. These are relatively new and are typically located in the backrests of the front seats. They protect rear passengers' heads during frontal collisions, especially children in rear-facing car seats. Center airbags, positioned in the center of the front seat to prevent occupants from colliding with each other during side- impact collisions; and inflatable seat belts, equipped with built-in airbags that inflate during collisions to provide additional upper body and torso support, enhancing overall occupant protection.

Initially, front airbags were standard, followed by side airbags, both of which have significantly reduced fatalities. Frontal airbags have shown a 29% decrease in driver fatalities and a 32% decrease in front-seat passenger fatalities.

But airbags are only effective if individuals follow the right rules and measures as follows:

1. Wear Seatbelts: Airbags work effectively when combined with seatbelt usage. Seatbelts secure occupants in place during airbag deployment, preventing additional impact injuries. In case the seatbelt is not worn, the airbag might feel like a hit in itself, apart from the crash.
2. Proper Seating Position: The airbag requires the right amount of space to deploy in case of a crash. Ensure there's at least a 10-inch space between you and the dashboard (for passengers) or the steering wheel (for drivers) to allow for full airbag deployment and optimal protection.
3. Monitor Airbag Malfunction Indicator: Check the airbag light upon starting your car; if it remains on for more than 10-15 seconds, there might be an issue requiring immediate servicing.
4. Original Equipment Manufacturer (OEM) replacement parts: It's crucial to have airbags replaced at a certified repair facility that utilizes genuine Original Equipment Manufacturer (OEM) replacement parts. This precaution is necessary to avoid counterfeit airbags, which could malfunction or release dangerous metal fragments during deployment.
5. Hand Positioning: The improper positioning of your hand can lead to your arms being thrown around in the cabin if the airbags were to deploy, in case of an accident. This could lead to injuries like broken hands or wrists. To prevent this from happening, maintain the hand positions at 9 o’clock and 3 o’clock, and avoid the centre of the steering wheel.
6. Avoid Front Seat for Children: Airbags have proven to be a great safety feature in a vehicle, but this only applies if you are over the age of 12 years old. The airbag is designed for the safety of an adult, this means that children under the age of 12 can as easily be injured or even killed by an airbag if they are in the front seat. The airbag inflates at a speed of 322km/h and the force created by the airbag can throw the child off the seat, given their light weight, and the momentum carried by an airbag while it is being opened in case of an accident.
7. Do Not Lean on Doors: Avoid leaning on doors to prevent interference with side airbags' deployment.
8. Keep Feet Off Dashboard: Something we see often, especially on long journeys or tiring drives, is people keeping their legs on the dashboard. This is highly dangerous. In case of an accident, the airbag when deployed can potentially break the passenger's legs and destroy the effectiveness of the airbag. To prevent this from occurring, keep your feet placed on the foot well of the car and maintain the right seating position.

Airbags are not substitutes for seat belts but work together to enhance occupant safety during accidents. Additionally, airbags for both front seats are mandatory in vehicles manufactured on and after April 1, 2021. Airbags significantly reduce fatality risks in accidents, but adherence to safety guidelines is crucial for their optimal effectiveness.