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How NHTSA Ratings Work


Improving NHTSA Ratings
A 2006 Buick Rainier performs a rollover test at a General Motors crash test facility in Milford, Mich., on Dec. 5, 2006.
A 2006 Buick Rainier performs a rollover test at a General Motors crash test facility in Milford, Mich., on Dec. 5, 2006.
AP Photo/Paul Sancya

Now you know how NHTSA ratings work, and why they're so important for car buying and car selling. But, when it comes to buying and selling cars, are NHTSA ratings the last word when it comes to safety?

Not really. NHTSA ratings are extremely helpful, but if you're really concerned about safety when you're buying a new car, you'll probably want to look beyond NHTSA ratings. One good place to look is the Insurance Institute for Highway Safety (IIHS). The IIHS also crash tests and rates cars, but its ratings are different -- and in some cases, more strict -- than NHTSA ratings. For example, the NHTSA doesn't give ratings on how a car might protect its occupants in rear-end collisions, and the IIHS does. Also, when it comes to rollover crashes, the NHTSA only rates how likely a car is to rollover. The IIHS performs roof-strength tests. Stronger roofs are key to protecting everyone in a car that's rolling over.

Finally, while both the NHTSA and the IIHS typically perform crash test that simulate collisions between two identically-sized vehicles, the IIHS occasionally goes beyond that. Noting the trend toward extra-small cars, in the summer of 2009, the IIHS performed crash tests that crashed small cars (the Toyota Yaris, Honda Fit and smart fortwo) into midsized cars -- with surprising results. Cars that rated well when crashed into similarly-sized vehicles didn't do so well when crashed into larger vehicles. That's information a lot of consumers would like to know.

But, the NHTSA is constantly refining and updating its ratings and crash tests. For example, the rollover rating was developed in response to the number of SUVs on the road and the increasing number of rollover accidents. By adding the rollover rating, the NHTSA gave consumers the information they needed to make the best car purchase for them.

For more information about NHTSA ratings and other related topics, follow the links on the next page.


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