Automakers are paying more attention to seat/head restraint designs than they did when the Institute first started evaluating restraint geometry in 1995. Cars have shown the most progress, and SUVs have made strides, too. But pickups and minivans lag behind.
For years head restraints were poorly designed. Most were adjustable, and even when adjusted to their highest positions they still weren't behind and close to the backs of many people's heads. This means they weren't in position to protect people's necks in rear crashes. In more recent years, head restraint geometry has gotten better. Most restraints can be positioned to protect the neck (see "More head restraints are positioned better to save your neck," Sept. 25, 2003). Many are designed to automatically move up and toward the head in a crash. Some vehicles have specially designed seatbacks to control torso movement in rear-end collisions.
There's still plenty of room for improvement. Rear crashes occur frequently, and neck injuries are the most common ones reported. Whiplash is the most serious injury reported in about 2 million insurance claims each year. These cost at least $8.5 billion.
Reasons for improvements
In 2004 the Institute added a dynamic test to evaluate seat/head restraints, using a dummy designed for rear testing — this in addition to the geometric evaluations. The Institute doesn't test seats with head restraints rated marginal or poor for geometry because they wouldn't adequately protect many people from whiplash.
In response, automakers have been making changes (see Status Report special issue: whiplash injuries, Sept. 16, 1995, and "Head restraints will be higher and closer to head under new regulation," Jan. 31, 2005). Volvo, which consistently has equipped cars with head restraints with good geometry, and Saab led the way with advanced seat designs. More recently, BMW and Mercedes have been making strides with restraints that activate in response to crash sensors rather than occupant motion.
Some automakers have been influenced by the Institute's Top Safety Pick award. Audi and Subaru redesigned the seats and head restraints in some models specifically to win in 2007 (winning vehicles have to earn good ratings in front, side, and rear tests and have electronic stability control). Using a better design in the MDX, Acura went from poor in 2006 to good and a Top Safety Pick award in 2007. Hyundai did the same with the Santa Fe.
How they rate
SUVs, pickup trucks, and minivans
Other improvements are being spurred by changes to federal safety rules. Front-seat head restraints will have to extend higher and fit closer to the backs of people's heads under a rule issued by the National Highway Traffic Safety Administration in 2004 (see "Head restraints will be higher and closer to head under new regulation," Jan. 31, 2005). Originally set to go into effect for front-seat head restraints in September 2008, the rule's effective date was delayed by the agency in response to petitions for reconsideration. Under the new phase-in schedule, manufacturers must start to fit better front-seat head restraints in 80 percent of their models beginning in September 2009. Front-seat head restraints in all new vehicles made after September 2010 must comply.
Which vehicles improved, which didn't
Cars and SUVs have made real progress during the past few years, but pickups and minivans haven't improved much. Twenty-three current car models are rated good for rear crash protection, while only 8 earned good ratings among 2004s. Seat/head restraints in the Audi A4 and S4, Honda Civic, Hyundai Sonata, Kia Optima, and Nissan Sentra improved to good in 2007 from poor in 2004. But the seat/head restraints in more than 60 percent of car models still fall short of state-of-the-art protection from neck injury.
Among SUVs, 17 of the 59 current models evaluated are rated good after dynamic testing compared with only 6 that earned this rating among the 44 evaluated for 2006. Several improved to good from poor, including 2 from Honda and 1 from Acura.
The redesigned Toyota Tundra is the only pickup rated good of the 17 current models evaluated, while the Chevrolet Silverado and GMC Sierra improved to acceptable from poor. In 2005, the Ford Ranger and Mazda B Series were rated good among 13 models tested.
Ratings of the 9 minivan models the Institute evaluated in both 2005 and 2007 didn't change, probably because most automakers didn't redesign their models or release new ones. Two new models, the 2007 Hyundai Entourage and 2006 Kia Sedona, do have seat/head restraints rated good. These minivans also are Top Safety Pick winners.
"There's lots of room for improvement," says David Zuby, Institute senior vice president for vehicle research. "We know many manufacturers are trying to fit better head restraints into their vehicles, and some have been working with us to boost their ratings as they introduce new models. Some manufacturers were waiting for resolution of regulatory issues before doing this."
Manufacturers are going in the wrong direction with a few models. The 2005 Ford Ranger and Mazda B Series had seat/head restraints rated good, but these were replaced in the 2006 model year with designs that are too short to protect many taller people. Now these pickups are rated poor for protection in rear crashes. The Dodge Ram slipped from acceptable in 2005 to poor in 2006. Among cars, seat/head restraints in the 2006 Chrysler 300 and 2007 Kia Amanti and Nissan Altima earned marginal ratings compared with acceptable scores in the 2004 model year.
Consistency across manufacturers' lines is a problem, too. Several have models with seat/head restraints rated good while other models are poor. Toyota puts good head restraints in the Tundra, for example, but those in the 4Runner and Sienna are poor and the ones in the Highlander and RAV4 are marginal. Ford's Edge, Freestar, and Taurus earn good ratings, but most other Fords are rated poor.
Issue extends beyond the United States
Designing better seats and head restraints has become a priority among researchers worldwide. The Institute joined with other whiplash injury prevention experts in 2000 to organize the International Insurance Whiplash Prevention Group to establish dynamic test procedures. Symposia have been convened on whiplash, with the next World Congress on Neck Pain slated for January 2008 in Los Angeles. Neck Injuries in Road Traffic and Prevention Strategies will meet in November in Munich.
"Because whiplash is a global problem, we've been working for years with our counterparts in other countries to better understand the issues and evaluate ways to reduce the injuries," Zuby says. "We know what designs work best in rear crashes, and we expect to see even more refined seat/head restraint combinations in future vehicles. The key will be getting automakers to put such designs in all of their vehicles."
The Institute's procedure for evaluating head restraint geometry is used by the Research Council for Automobile Repairs, a worldwide consortium of research centers sponsored by insurers. U.S. federal safety ratings don't cover vehicles' seat/head restraints, but the government has expressed interest in adding the Institute's ratings to its New Car Assessment Program results. The European New Car Assessment Programme also is considering the addition of a head restraint evaluation component.
"Our evaluations suggest this worldwide attention is yielding results," Zuby says. "We're seeing more seat/head restraints rated good and acceptable than we used to. It's clear that many foreign and domestic automakers are moving in the right direction."