Commentary: Gas-Guzzlers Are Safer? Pure Bunk

By John Carey

If Americans' cars, SUVs, and pickup trucks went farther on each gallon of gas, the country would reap big rewards: less pollution, less potential global warming, and less dependence on Middle Eastern oil. But whenever Congress tries to pass measures to boost mileage demands, Detroit screams bloody murder: Higher standards will kill thousands of Americans, it argues, since higher-mileage cars are lighter and less safe.

The claim has a grain of truth. If I crash a Geo Metro head-on into your Chevy Suburban at high speed, I'll be dead, while you might get away with minor injuries. In a collision, "everyone would agree that you tend to fare better in the heavier vehicle," says transportation and energy policy expert David L. Greene of Oak Ridge National Laboratory.

But beyond that, the argument is bunk. "An increase in fuel economy does not have to translate into a decrease in safety," says Adrian K. Lund, chief operating officer of the Insurance Institute for Highway Safety. Indeed, new studies show not only that drivers of pickups and SUVs are killed at a higher rate than drivers in, say, Toyota Camrys, but also that a higher-mileage fleet could actually reduce overall deaths. There's no need to drag people out of SUVs and force them into Geo Metros. Our environmental and safety goals can be achieved with market mechanisms, such as increasing gas prices, rather than mandated fuel standards.

The first myth to be busted is that better gas mileage means smaller--and less safe--cars. My own trusty 1989 Honda Accord is rated at 34 mph on the highway: darn good. But today, I can buy a same-size Toyota Corolla with 32% more horsepower, much better crash protection, and a 40-mpg highway rating. With innovations such as variable valve timing, even many of today's big cars and trucks can get a healthy mileage increase--enough to save several million barrels of oil a day. "It is technically feasible and potentially economical to improve fuel economy without reducing vehicle weight or size," concludes a recent report from the National Academy of Sciences.

Additional mileage gains would come from making vehicles lighter--not smaller--by switching to high-strength steel, aluminum, and plastics. These materials cost more, but would allow manufacturers to maintain the dimensions of today's cars. In safety terms, that means plenty of "crush space," which softens the impact.

Meanwhile, the relationship between weight and safety tends to get misstated. Opponents of higher corporate average fuel economy (CAFE) standards often cite a 1997 study by the National Highway Traffic Safety Administration (NHTSA). It estimated that for every 100-pound reduction in car weight, 250 more people die each year. Thus, the 700-lb.-per-vehicle weight loss from 1976 to 1993, caused largely by CAFE standards, led to an extra 2,000 deaths in 1993.

But this study was seriously incomplete. It used data only up through 1993 models--before most cars came with side-impact protection, air bags, and other features. "If you think about the advances in safety technology, there have been tremendous improvements since 1993," says John German, Honda's manager of environment and energy analysis. So Honda commissioned DRI to redo the NHTSA study with data up to 1997 models. The result? A 100-lb. reduction in vehicle weight wasn't associated with more deaths.

Similarly, a new analysis by Marc H. Ross of the Physics Dept. at the University of Michigan and Tom Wenzel of Lawrence Berkeley National Laboratory finds that real driving risks have little to do with weight. Drivers of Ford Explorers are 61% more likely to die than drivers of 1,000-lb.-lighter Toyota Camrys. "People buy SUVs thinking that they will get a safety benefit because of the weight, but that benefit is outweighed by the increased rollover risks," explains Oak Ridge's Greene.

And while some small cars, such as the Dodge Neon, have high fatality rates, others, like Honda's Civic, have lower driver-death rates than the average SUV. Part of that is due to differences among drivers. But to Ross, a key conclusion is that better design and construction trump size and weight.

Size does matter when really big vehicles crash into much smaller ones. But this problem is as much a matter of design as weight. The high frames of pickups and truck-based SUVs typically override a car's crash protection, acting like battering rams. "Being hit by an SUV is twice as risky as being struck by a car of the same weight," says Hans C. Joksch, a scientist at the University of Michigan Transportation Research Institute. Some vehicles are even worse. In Ross and Wenzel's analysis, Dodge Rams are more than five times as dangerous to other drivers as are Buick LeSabres or Honda Accords.

As a result, the current trend of making lower-riding SUVs and pickups should bring a big safety benefit. More gains would come from making these trucks lighter and more fuel-efficient. One way to do this is to raise CAFE standards. But higher fuel-economy standards can have an unintended effect: By making vehicles go farther per gallon, they reduce the cost of driving. That may make people drive--and crash--more.

A better approach is to harness market forces. Raising gas taxes a few cents per month over many months would give consumers an incentive to buy higher-mileage vehicles, argues Leonard Evans, a former traffic and safety researcher at General Motors Corp. The slow phase-in would be relatively painless economically, since carmakers would have time to design and build the fuel-sipping cars--and the savings from higher efficiency would offset the slowly rising price of gas. And since the pocketbook hit would be biggest for heavy gas-guzzlers, they would get the biggest percentage boost in fuel economy through new technologies. The bottom line: America would use less gas, and its roads would be safer for everyone.

Corrections and Clarifications The photo in ``Gas guzzlers are safer? Pure bunk'' (Environment, Sept. 9) depicted a Dodge Ram 3500 Quad Cab SLT but listed specs for the 1500 model. The 3500 weighs approximately 6,200 pounds, with 11/15 mpg. The data on death rates, however, were for all models of Dodge Ram.

Carey covers science and the environment.

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