THE GOODS : Few Safety Zones With Rear-End Crashes

When the federal government mandated that auto makers install a high-mounted brake light on each new vehicle a decade ago, expectations were that the rule would result in a 50% reduction in urban rear-end crashes.

The initial results were quite good, but as the years passed something predictable happened: Motorists became accustomed to seeing the third brake light and no longer respond as quickly when it comes on.

The actual reduction in urban rear-end crashes since the introduction of the lights has amounted to only 5%, according to a new study by the Insurance Institute for Highway Safety.

Meanwhile, the medical and economic toll from whiplash injuries that result from rear-end accidents has continued to climb.

Injured motorists annually file 4 million accident claims in which whiplash is the most serious injury, costing $10.2 billion. Another 2 million accident claims include whiplashes with more severe injuries.

Whiplashes are supposed to be prevented by headrests, but the vast majority of headrests in new models perform poorly, the safety institute said.

The study looked at 164 car models and found just 42 have acceptable or even marginally acceptable headrests, while 117 were rated poor. A smattering of Volvo, Honda, Porsche, BMW, Mercury, Nissan and Saab models were rated good or acceptable.

When the government first required head restraint, many auto makers designed seats with high backs to protect the neck when the head jerks back in a rear-end collision. But increasingly, they have migrated to adjustable headrests that provide less overall protection, the study asserts.

It doesn’t take much of an accident to injure a neck. Typically, the injuries result from collisions below 12 miles per hour and in the vast majority of the cases the cars don’t even have to be towed away.

The occupants inside these cars would fare well if manufacturers provided restraints that met two general guidelines: They should be high enough to reach about two inches above the top of the occupants’ heads and they should be positioned within three inches of the backs of the heads. Adjustable headrests should be kept in the proper placement for the heights of occupants, and are safer if they are the type that lock into position.

* Vartabedian cannot answer mail personally but will attempt to respond in this column to automotive questions of general interest. Do not telephone. Write to Your Wheels, 1875 I St. N.W. #1100, Washington, D.C. 20006.