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5 Things You Didn't Know About Automotive Testing


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How do those crash ratings actually work, anyway?
This photo provided by the Insurance Institute for Highway Safety shows a frontal offset crash test of a 2008 Smart Fortwo.
This photo provided by the Insurance Institute for Highway Safety shows a frontal offset crash test of a 2008 Smart Fortwo.
AP Photo/Insurance Institute for Highway Safety

Car commercials, if they can legitimately make the claim, like to brag about things like getting a "five-star" safety rating. For a large segment of the driving public, knowing that one's family is well-protected in case of a crash is a top buying consideration.

But besides being a great marketing hook, what does that bit of safety info really mean?

To help answer that, you should know that it's actually two bodies that conduct crash testing to determine a car's safety rating. One is the federal government -- specifically, the National Highway Traffic Safety Administration (NHTSA). The NHTSA has been responsible for mandating many of the safety features that we often take for granted -- things like seat belts and padded dashboards. The other major testing body is the Insurance Institute for Highway Safety (IIHS), an organization supported by the major car insurance firms.

The two testing bodies actually use two different ratings criteria (as well as having somewhat different crash test procedures).

The NHTSA uses the star system we're all aware of from car commercials. The frontal crash ratings, for instance, go from poorest, which is one star (46 percent or higher chance of serious injury in a collision), to the best, which is five stars (chances of being seriously injured in a collision are just 10 percent or less).

The IIHS simply ranks vehicles as Poor, Marginal, Acceptable or Good.

Those ratings are conferred after literally a battery of crash tests that include frontal collisions -- up to 40 miles per hour (64.4 kilometers per hour), side collisions and rollover tests [source: Greco].

Car testers cover a lot of ground, from ride and handling to interior rattling to how well the heating and air work. Automakers generally work really hard at eliminating noise, so it might come as a surprise to learn that there's a certain type of vehicle they actually want to make some noise.


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