Understanding Car Safety Ratings
Car safety ratings are generally high on a car buyer's list of concerns, especially for a buyer with a family. But what actually constitutes a crash-worthy vehicle? Fortunately, the Insurance Institute of Highway Safety (IIHS) answers this question. Each year, the independent research organization identifies its Top Safety Picks, a coveted roster of passenger vehicles with the best car safety ratings.
To determine how well a vehicle will protect occupants in an accident, IIHS puts vehicles through five tests: moderate overlap front, small overlap front, side, rollover and rear. Each test will earn a rating of Good, Acceptable, Marginal or Poor. For a vehicle to make the Top Safety Pick list, it must receive a Good rating in the moderate overlap front, side, rollover and rear tests, regardless of how it does in the small overlap front test. For a Top Safety Pick + (plus) designation, the vehicle must earn Good ratings in at least four of five tests and no less than an Acceptable rating in the fifth test.
Moderate Overlap Frontal Test
This test challenges the structural integrity of the occupant compartment in a near head-on collision. A vehicle is launched at 40 miles per hour toward a 2-foot-tall barrier. At impact, 40 percent of the width of the car strikes the barrier on the driver's side, which mimics a frontal offset crash between two comparably sized vehicles traveling under 40 mph.
Small Overlap Frontal Test
When the front corner of a vehicle collides with another vehicle or a static object, occupants are jarred both forward and sideways. This test challenges the effectiveness of safety belt and airbag systems. The vehicle travels at 40 mph toward a 5-foot-tall barrier, and 25 percent of the total width of the vehicle strikes the barrier on the driver side.
Broadside collisions are troubling because the sides of vehicles don't provide the space to adequately shield occupants. In this test, a 3000-lb sled-barrier T-bones the driver's side of a car at 31 mph.
When a vehicle rolls, the roof can crush downward. In the roof strength test, a metal plate is pushed against one side of a roof to test its strength-to-weight ratio. To earn a Good rating, the roof must withstand a force of four times the vehicle's weight before reaching five inches of crush.
This test evaluates the geometry of a vehicle's head restraints and seat backs to determine occupant protection in a rear collision. The vehicle is struck from behind to measure potential "whiplash" injuries to a passenger.
See if your car of choice is an IIHS Top Safety Pick.