It seems that the Insurance Institute for Highway Safety has a pretty good crystal ball with its side-impact crash tests. In a recent study, researchers found that drivers of vehicles that receive a Poor rating in the IIHS side-impact test are three times more likely to die in real-world crashes than drivers of vehicles that get a Good rating.
A vehicle’s structure — not just how many airbags it has — plays a key role. Specifically, the study found that a driver’s odds of dying when another car crashes into the driver’s side are 70 percent less if the driver is in a vehicle that was rated Good in side-impact protection than if that driver were in a vehicle that was rated Poor.
A driver of a vehicle rated Acceptable is 64 percent less likely to die in that side crash than a driver of a vehicle rated Poor. And a driver of a vehicle rated Marginal is 49 percent less likely to die than one in a vehicle rated Poor.
Women need to know that the results apply to them as well, since the insurance institute uses a crash test dummy the size of a small woman in its tests. That is important since the heads of shorter drivers are more likely to be hit in a side crash, especially when hit by the vehicle the height of a sport-utility vehicle or pickup truck.
The insurance institute’s test involves a 3,300-pound deformable barrier the height of one of those taller vehicles hitting a vehicle on the driver’s side traveling at 31 mph.
This chance-of-dying study looks at the side-impact ratings a bit differently than usual. The usual ratings look at several ways people are protected in a crash, including by airbags and structure. This analysis looked at the importance of a vehicle’s structure, not its airbags, in a side crash and what its structure means to the risk of dying in a real-world crash. The study looked at the risk to the driver only, not the other occupants.
Side crashes can be particularly deadly because the sides of vehicles don’t have as much space as the fronts of vehicles to absorb crash energy and protect occupants.
That is one reason why airbags are so important.
MOTOR MATTERS DOWN THE ROAD BY CHERYL JENSEN
The institute already knows that it helps to add side airbags to vehicles, especially those with head protection, said Adrian Lund, the institute’s president. But the institute’s side-impact tests, he said, were intended to do more. They were intended to motivate improvements to a vehicle’s side structure because airbags and structure are complementary.
Side airbags are not enough on their own, Lund said because they don’t control how far one vehicle crashing into another vehicle intrudes into the compartment that is supposed to be protecting the occupants.
“And structure is not sufficient either because you aren’t going to be able to protect the head,” he said.
So the purpose of the analysis was to see if the institute’s testing was resulting in improvements over and above what the airbags were doing, Lund said. It found that a vehicle with a Good rating for structure affords significantly more protection. The IIHS took its crash test data for vehicle intrusion only and compared it to federal data on side crashes from 2000 to 2009. Only vehicles with standard side airbags to protect both the head and torso were included to better focus on structure.
Lund’s advice for shoppers is this: “Even if the cars you are choosing among all have airbags, take the one that has a Good rating from the insurance institute because it matters.” For more information, visit www.iihs.org. — Cheryl Jensen, Motor Matters
Copyright, AutoWriters Associates Inc., 2011