How airbags work
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Designed to protect vehicle occupants in the event of an accident, airbags deploy when the vehicle collides with another object or otherwise slows down rapidly. While absorbing impact energy, vehicle owners need to be aware of the location of the various airbags in their vehicle, as well as any safety issues associated with the use of airbags.
Some important considerations include knowing how to deactivate an airbag when needed, determining when a mechanic needs to replace an airbag, and recognizing common problems and symptoms of airbag problems. A bit of knowledge about how airbags work can help put all of this into perspective.
Basic principle of airbag
The airbag system in a vehicle works by using sensors monitored by the airbag control unit (ACU). These sensors monitor important criteria such as vehicle acceleration, impact areas, braking and wheel speeds, and other important parameters. By detecting a collision using sensors, the ACU determines which airbags should deploy based on the severity, direction of impact and a host of other variables, all within a split second. The initiator, a small pyrotechnic device inside each individual airbag, generates a small electrical charge that ignites the combustible materials inflating the airbag, helping to reduce damage to the occupant's body upon impact.
But what happens when a car passenger comes into contact with an airbag? At this point, the gas exits through the small vents, releasing it in a controlled manner. This ensures that the energy from the collision is dissipated in a way that prevents injury. The chemicals most commonly used to inflate airbags include sodium azide in older vehicles, while newer vehicles typically use nitrogen or argon. The entire process of impact and deployment of the airbag occurs in one twenty-fifth of a second. About a second after deployment, the airbag deflates, allowing passengers to exit the vehicle. The whole process is very fast.
Where to find airbags
The biggest question, aside from how an airbag works, is where exactly can you find one in your car? Some common areas where vehicle manufacturers place airbags include driver and passenger side front airbags, and side, knee, and rear curtain airbags, among other locations inside the vehicle. Essentially, designers are trying to identify points of possible contact between occupants and the car, such as the dashboard, center console, and other areas that pose a risk of injury from an impact.
Parts of the airbag system
Air bag: Made of thin nylon fabric, the airbag folds into a space on the steering wheel, dashboard, or elsewhere inside the vehicle.
Collision sensor: Crash sensors throughout the vehicle help determine the severity and direction of an impact. When a certain sensor detects an impact of sufficient force, it sends out a signal that fires the igniter and inflates the airbag.
igniter: On a hard impact, a small electrical charge activates the chemicals around it, creating a gas that inflates the airbag.
chemical: The chemicals in the airbag mix together to form a gas such as nitrogen, which inflates the airbag. Once inflated, tiny vents allow the gas to escape, allowing passengers to leave the car.
Airbag safety
Some vehicle drivers and passengers may think that seat belts are unnecessary if you have an airbag system. But the airbag system itself is not enough to prevent injury in a crash. Seat belts are an essential component of a car's safety system, especially in a frontal collision. When the airbag deploys, a pin in the seatbelt deploys, locking it in place and preventing occupants from moving further forward. Most often, when the airbag deploys, the seat belt must also be replaced.
Some of the safety issues associated with airbags include sitting too close to the airbag, placing children under the age of 12 in the front passenger seat, and placing children in the correct direction in the back of the vehicle according to their age and weight.
When it comes to airbag distance, you need to make sure you sit at least 10 inches away from the airbag on your steering wheel or passenger side dashboard. To achieve this minimum safety distance from the airbag, follow these steps:
Move the seat back, leaving room for the pedals.
Tilt the seat back slightly and raise it if necessary to provide a good view of the road while driving.
Tilt the handlebar down from your head and neck. Thus, you direct the blow to the chest area in order to avoid injury.
Children require a completely different set of rules. The force of the front passenger airbag deployment can injure or even kill a small child sitting too close or being thrown forward when braking. Some other considerations include:
Using an age-appropriate child car seat in the rear seat.
Appeal to infants weighing less than 20 pounds and less than one year old in a rear-facing car seat.
If you must seat children over one year of age in the front passenger seat, be sure to move the seat all the way back, use a forward-facing booster or child seat, and use a properly fitted seat belt.
How to turn off the airbag
Sometimes, if there is a child or a driver with certain medical conditions in the front passenger seat, it is necessary to turn off the airbag. This usually comes in the form of a switch to disable one or both of the front airbags in the vehicle.
You might think that the airbag should be disabled in the following cases, but according to the doctors of the National Conference on Medical Conditions to disable the airbag, the following medical conditions do not require the airbag to be disabled, including those with pacemakers, glasses, and pregnant women, and also an extensive list of other illnesses and diseases.
Some vehicles include a switch for the front passenger's side airbags as an option from the manufacturer. Some of the conditions that require the passenger airbag to be disabled include vehicles without a rear seat or with a limited number of seating arrangements that must fit a rear-facing car seat. Fortunately, if necessary, a mechanic can turn off the airbag or install a switch on the car.
Replacing a deployed airbag
After the airbag has deployed, it must be replaced. Airbag sensors located in the damaged part of the vehicle also need to be replaced after the airbags have deployed. Ask a mechanic to do both of these tasks for you. Another problem area that you may encounter when using your vehicle's airbags involves the airbag light coming on. In this case, have a mechanic check the airbag system to determine the problem and the need to replace any airbags, sensors, or even the ACU.
Another important action to take to prevent airbag problems is to check them regularly to determine if they are still safe to use or need to be replaced.
Common problems and symptoms of airbag problems
Pay attention to these warning signs that indicate there may be a problem with your airbag and act quickly to fix the problem:
The airbag light comes on, indicating a problem with one of the sensors, the ACU, or the airbag itself.
Once the airbag has deployed, the mechanic must remove and either reset or replace the ACU.
Be sure to check your seat belts after an accident to see if they need to be replaced by a mechanic.
