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When Do Side Airbags Deploy? Facts & FAQ

side airbag

Side airbags are extremely useful safety features on late model vehicles. Studies conducted by Insurance Institute for Highway Safety and the National Highway Traffic Safety Administration have shown marked reductions in fatalities for vehicles that use side airbags as opposed to vehicles that do not. (SUVs saw the most benefits from side airbags.) So, when do side airbags deploy? Do they always go off in an accident? How fast do you have to be going to trigger the side airbags?

Side airbags typically deploy in the event of any sort of side impact event. If a car is struck on the side by another vehicle or an object, it will quickly trigger the side airbags. The speeds to trigger side airbags can be extremely low in some situations. Side impacts can be extremely dangerous and deploying side airbags quickly and efficiently is critical to seeing positive results. While there are a variety of different types of vehicle wrecks and accidents that can happen on the road, there are two types of crashes where side impacts are the most likely to deploy.

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Crashes Where Side Airbags Typically Deploy

motorcycles crash collision hit by car
Image Credit: faboi, Shutterstock

Heavy Side Impact (T-Boning)

A heavy side impact or a perpendicular crash is colloquially known as being T-boned. These crashes are very dangerous as the heaviest part of one vehicle (the engine block) makes contact with the relatively thin door panel of another vehicle. Occupants can easily be injured in powerful side impacts. The side airbags are designed to mitigate these risks and detonate extremely quickly if a side impact is detected.

Unlike a head-on crash, there is not much space or time for the airbags to deploy when an object strikes the side of the vehicle. In a head-on collision, the force or the object has to travel through the entire engine compartment, through the frame, and then into the vehicle. The side impact only has to transfer force through the door and into the occupant. For that reason, side airbags will always go off in the event of a side impact event.

Roll Over Crash

Rollover crashes often cause the side airbags to deploy. Many side airbags are rigged to detonate when a car begins to roll over. Side airbags help protect the occupant from impacting the ground or another car in the event of a rollover crash. Rollover crashes can sometimes also strike nearby objects like fences, trees, guardrails, or power poles. The side airbags are designed to help mitigate the force and damage to the occupants from a car hitting any of these types of objects during a rollover.

When the side of the vehicle rotates all the way around and makes contact with the ground or an object, the airbags are going to react the same way as though the car was struck on the side by another vehicle.

crashed car on the field
Image Credit: Piotrg255, Pixabay

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How Fast Do You Have to Be Going for Side Airbags to Deploy?

According to the National Highway Traffic Safety Administration, you only have to be going 8 mph for some side airbags to deploy. That is because the airbags are designed to prevent objects from entering the car and injuring the occupants. Side airbags are more sensitive to narrow areas of pressure caused by objects like trees or poles and will deploy if a concentrated amount of force hits the car in a skinny shape. A tree or pole can be extremely deadly if it enters the car.

If the car is struck by a large object on the side, like another car, the threshold rises to around 16 mph. If you are stationary, the threshold is around 18 mph.

Can Side Airbags Deploy in a Head-On Collision?

Yes. If the strength of the impact or the angle of the collision is just right, side airbags can deploy even if you are in a head-on collision. A powerful head-on collision can send strong enough shock waves through the vehicle to trigger the side airbags. If the collision is angled to one side or the other of the front of the car, it can also trigger the side airbags to deploy. This is not common, but it does happen in certain situations.

If the Side Airbags Deploy, Is My Car Totaled?

No. The deployment of airbags does not mean that any car is totaled. A car is deemed totaled by an insurance company if the estimated cost to repair the vehicle is higher than the vehicle’s worth. Airbags often only deploy in serious crashes, so the likelihood that your car is totaled when the airbags deploy is higher, but the two things are not directly connected. If you get in a wreck with a new car worth $30,000 and the repair bill is $25,000, the insurance company is going to opt to repair instead of replacing, which means your car would not be considered totaled even if the side airbags deployed.

deployed airbags
Image Credit: Maksim Vivtsaruk, Shutterstock

Do All Cars Have Side Airbags?

No. Side airbags are not a mandated safety feature required by law. Side airbags are growing more common with each passing year, but not all vehicles have them. Most major manufacturers include side airbags as a standard safety feature on their best-selling vehicles, but since they are not mandated, some models go without them. If you are curious if you have side airbags, check your owner’s manual to see if your specific make and model has them included. Also, be sure to ask the dealer if your prospective car is equipped with side airbags when you are shopping.

Cars that often forgo side airbags include sports cars and super compact cars. Some budget vehicles might also drop side airbags in order to save money on the bottom line.

car and road divider Conclusion

If you have your side airbags deployed during a crash, realize that they are trying to help save your life. Side airbags are very effective at reducing the number of traffic fatalities that occur every year. Side airbags typically deploy whenever an object strikes the side of a vehicle with enough force. Having your airbags deployed does not necessarily mean that your car is totaled. Some mild incidents can cause side airbags to deploy and not leave your car in a non-repairable condition.


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Featured Image Credit: Attapon Thana, Shutterstock


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