How Much Does Size Matter in a Car Crash?

How Much Does Size Matter in a Car Crash

The compact car and SUV segments are among the most active segments in the car market right now. With gas prices fluctuating wildly, the trend is to purchase more fuel efficient vehicles - which usually means smaller vehicles. Additionally, small cars tend to be easier to control, more agile and sporty, and easier to park.

One raging question about compact vehicles is related to their safety. In a smaller car, are you as safe as you would be in a larger vehicle? Are you more likely to be injured or killed in a car crash when compared to the occupants of a larger car or truck? Does size really matter in a car crash?

Bigger is better

If you want a simple answer, then yes, larger vehicles are safer - but size doesn’t make as much of an impact (pun intended) as you may think. Here’s an explanation:

Mass is a factor. Imagine in the sixties and seventies when vehicles were as big as boats. Every vehicle was made with reinforced steel, and the name of the game was to build bigger and stronger. In a collision, the intention was to be the bigger of the involved parties so your vehicle’s weight would keep you safer. If a large car or truck hit a small sedan, it could push the sedan all over the road, affecting the smaller car much more than the larger car. There was a huge space between the front bumper and the cabin, meaning the impact wouldn’t reach the passengers as quickly as it would in a small car.

The same rings true in today’s car market, yet to a much lesser extent. Modern vehicles are all built with safety in mind, including crash standards. Where a truck could have virtually run over a small car in previous decades, now they are mandated to keep their impact point at a relatable height to a small car. Both have crumple zones to absorb some of the collision, and both have airbags and supplemental restraint systems to cushion the blow. Compared to previous generations, small cars have made leaps and bounds in safety.

Mass still factors in, though, because the larger vehicle can still push the smaller car around on the road. That can mean subsequent accidents or injury from other extenuating circumstances, but by and large, the accident itself will be less in favor of the larger vehicle than it used to be.

Vehicle design is influential

If you compare crashes between inequal vehicles from the past decade and the sixties, you’ll find that the injury rates are phenomenally reduced now. Largely, that’s due to vehicle design. There are plenty of systems used today that are meant not only to reduce injury, but also to avoid collisions in the first place.

Crumple zones. Crumple zones are designed into every modern vehicle as a way of saving lives from impact trauma. The theory is that when a vehicle absorbs the energy before it reaches the passenger compartment, the occupants experience less trauma and injury. This theory has been thoroughly tested and holds up to scrutiny.

The frame rails, hood, suspension, firewall, and even the windshield provide structural integrity during normal driving, but on an impact they collapse in a controlled manner to absorb kinetic energy and reduce the effects felt inside the car.

Both small cars and large cars have crumple zones built in now, narrowing the gap between the safety of a large vehicle and a small one.

High-strength materials. Where the focus in older cars was to build parts thick and sturdy, the modern focus is to build lightweight parts that are engineered to be strong and rigid. The use of high-strength materials is paramount to a vehicle’s structural integrity, yet the engineered bracing allows for crumple zones to be designed into the components for protection in an impact.

The same high-strength materials are used in both small vehicles and large ones, again narrowing the disparity in vehicle safety.

Safety systems. A handful of safety components have become almost standard equipment across the board, such as anti-lock brakes (ABS) and traction control. Airbags are standard equipment on all passenger vehicles, as well as seat belts. With the safety components and their usage becoming regulated and enforced, the injuries seen in a collision have been greatly reduced.

With safety systems taken into account, the gap between large vehicle and small vehicle safety is even more narrow.

Vehicle control. Smaller vehicles have an edge over large cars and trucks - in most cases, this advantage is in their handling and control. Small vehicles are typically easier to control with more nimble handling, sporty suspension, and better traction that can greatly assist a small car to avoid a collision in the first place. A larger vehicle will have a much more difficult time changing their direction if a crash is impending than a smaller vehicle.

If you’re looking for a simple answer, larger vehicles are still safer - but the gap is much smaller now compared to the disparity just a few decades ago. The larger mass can still push the smaller mass around, but with similar systems and designs, and the edge in vehicle control going to the small cars, the size of vehicle means less now than it ever has.

Safety is mainly in the driver’s control. Responsible, attentive driving will prevent more collisions and keep occupants safer than relying on your vehicle to keep you safe during an accident.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

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