
What do the different NHTSA rollover ratings mean?
The National Highway Traffic Safety Administration (NTHSA) was the first agency to begin testing for roll-over possibilities. The test involves a new vehicle making an emergency lane change. The NHTSA test observes the outside tires. If the abrupt change results in the outside wheels lifting two or more inches above the road, then a roll-over is recorded. The test results indicate the likelihood of a rollover—not the resulting injuries.
Since the likely outcome of a roll-over event is devastating injuries, the purpose of the test is to eliminate the occurrence of roll-overs...