Why are they fitted and what should you know about them?


• What is an airbag and how does it work?
• Airbags for all types of protection
• From origins to today
• Important things to note about airbags
• In the event of an accident


If you have a car that is less than 20 years old, it is almost certain to have airbags. These are a crucial safety feature which, hopefully, most motorists will not have to encounter first hand, however it is worth knowing the basics, so you can be prepared.

What is an airbag and how does it work?

Without wanting to state the obvious, an airbag is pretty much what you would imagine from its description. However, to be more specific, it is a bag that is inflated with a gas –  which is not actually air, but most often some type of nitrogen-based gas mixture – that inflates rapidly to cushion the occupant of a vehicle in the event of very quick deceleration, of the sort usually encountered during an accident.

Airbags have their own control units with sensors that detect extreme deceleration. The bag itself is folded into a very small space, and once the detectors trigger airbag deployment, using a chemical reaction, it inflates in a fraction of a second.

Once having done its work of helping the vehicle occupant to avoid hitting the various parts of the car that the particular airbag protects, it quickly starts to deflate through vents that are integral to the system, ensuring there is no chance of an airbag suffocating the person it is meant to be helping.

An airbag for all types of protection

Nowadays there are airbags for various different parts of a car, and in some cases even airbags to help protect pedestrians that might be hit by the vehicle involved in the accident. It is pretty accurate to say that, generally, the more expensive a vehicle, the more airbags it is likely to have, although even the cheapest cars available on sale in the UK will have airbags as standard, one that deploys from in front, usually through the centre of the steering wheel and another from the side.

Airbags are often designed to protect specific areas of the body, or cater for a particular type of accident. Side ‘curtain’ airbags offer head protection, and there are even curtain airbags to protect the vehicle occupants in the event of it rolling over, as well as side torso airbags located in the seat itself, which help protect the occupant from hitting the door. Many cars also have airbags specifically designed to protect the occupants’ knees, while some have airbags that inflate behind the rear passengers, to help in the event of the vehicle being hit from behind.

There are some vehicles that feature seatbelt airbags to help spread the force generated in an accident away from the area of the seatbelt itself.

Even motorcyclists can benefit from airbags that are integrated into protective leathers, a development that has been used to great effect to help motorcycle racers in the event of them coming off their machines.

From their origins to today

Originally it was envisaged that airbags would replace seat belts. However, it was discovered, before the research had been conducted for very long, that airbags are at their most effective when used in conjunction with seat belts –  airbags being an active supplementary safety system, to the passive safety afforded by the seatbelt.

Although it was first thought that airbags might need to be replaced every 10-15 years, fitting an airbag is a complicated and costly affair and therefore they have been developed to last the lifetime of the vehicle.

Important things to note about airbags

Initial worries that airbags might go off spontaneously have largely proved to be unfounded, however there are some aspects of vehicle airbags that it is worth paying special attention to.

Airbags are designed to be effective for occupants who are sitting, forward-facing in a normal seated position. Passengers sitting sideways, leaning back talking with those in the rear or lounging in the front seat with their feet on the dashboard, are at significant risk of injury from the airbags themselves, should they be deployed in an accident.

If your airbag warning light comes on, you should take your car in to be checked by a professional. Car diagnostic systems should quickly pinpoint what the issue is and a technician should be able to take the appropriate steps to remedy the problem.

Furthermore, even though there isn’t a specific check on the airbag system, as part of an annual MoT test, if your airbag light is on during the examination, the vehicle will fail because of it.

Also, if you have a rear facing child seat, it should not be used where there is an airbag, as it can injure the child if deployed – hence the prominent warnings inside the car and in the owner’s instruction manual, that you need to switch off the airbags when using such a seat. Naturally, if the off switch is not obvious, refer to the manual.

If you are in an accident when an airbag is deployed

Hopefully, you won’t ever be in the situation to experience the deployment of an airbag, but if you are, you might find that the car fills with ‘smoke’. Obviously, it isn’t actually smoke, it is likely to be powder such as talcum powder, so don’t panic that the car is on fire as it will disperse quite quickly.

All in all, although the deployment of the airbags makes things a bit messy, the additional protection that they offer, in the case of a major accident, makes them one of the greatest safety innovations of the last 50 years.


Article from in the category: Magazine