ARLINGTON, Va. — The latest ratings of head restraints in more than 200 passenger vehicles indicate these devices are getting better. Twenty-nine percent of the vehicles, all 2001 models, have head restraints rated good, and another 24 percent have acceptable head restraints. This is the first time that more than half of all new passenger vehicles offer restraints rated good or acceptable by the Insurance Institute for Highway Safety.
Head restraints that meet positioning requirements can reduce the risk of neck injury in rear-end crashes. Such injuries cost at least $7 billion per year.
The Institute rates most head restraint designs good, acceptable, marginal, or poor based on how a restraint meets height and backset requirements for an average male. The top of a restraint should be at least as high as the top of an occupant's ears. The backset, or distance between the back of an occupant's head and the front of the head restraint, should be as small as possible.
The Institute has rated head restraints in 1995, 1997, 1999, and 2001 models. There's a dramatic comparison among these results. It was almost impossible to find a good head restraint in a 1995 model. Those in just five cars were rated good, and three of the five cars were Volvo models. By the 1997 model year, good and acceptable head restraints were easier to find but still in fewer than one-fourth of the cars in which Institute researchers measured head restraint geometry. Among 1999 models, fewer than a third of the restraints measured were rated good or acceptable.
HEAD RESTRAINT IMPROVEMENTS
Percentage of head restraints rated:
"More and more automakers are finally getting the message," says Institute chief operating officer Adrian Lund. "In 1995, unless you were short, it was hard to find a car with a head restraint high enough to provide protection. But now, even taller people have a good chance of getting head restraints that will protect them. This marks a sea change."
The restraints in some vehicles are active. That is, they're designed to move into position during a rear impact. Such head restraints are rated good by both the Institute and the Research Council for Automobile Repairs, a consortium of international research centers funded by automobile insurers. The automatic good ratings will continue until comparative dynamic tests for whiplash protection are available. The Institute and others are planning such tests. "Until then, we're crediting the advanced systems and giving them good ratings. We'll do this until a dynamic test protocol is in place," Lund says. "Our testing to date indicates such ratings are warranted."
Saab's active restraint and General Motors' "catcher's mitt" design both feature a head restraint that moves up and forward as an occupant's torso loads the seatback in a rear-end collision. All Saabs since the 1999 model year have such restraints, as do current Buick LeSabre, Pontiac Bonneville, and Oldsmobile Aurora models. Nissan offers a similar active head restraint design in its Maxima and Infiniti I30, Q45, and QX4 models.
"It's encouraging to track all the manufacturer activity aimed at improving head restraints," Lund says. "Generally speaking, restraints are getting higher and closer to the head, and many more adjustable restraints now come with locks to keep them in position."