By Justin Hyde
DETROIT, Oct 14 (Reuters)
- Cutting the weight of the average car or truck would likely increase
the risk that its occupants could die in a crash, according to a federal
study released on Tuesday that could play a role in future fuel economy
standards.
But the same study said heavier trucks -- pickups and sport utility
vehicles weighing more than 5,000 pounds -- could shed 100 pounds with
no change in their safety and reduce the danger they pose to other vehicles
in accidents.
The report by the
U.S. National Highway Traffic Safety Administration may bolster the
case of some automakers, most notably General Motors Corp.(NYSE:GM -
News), which had argued that tougher federal fuel economy standards
might force them to build lighter, less safe vehicles.
"Automakers
believe that the report confirms what we've known for a long time --
that downsizing and down-weighting vehicles has an adverse impact on
safety," said Alliance of Automobile Manufacturers (News - Websites)
spokesman Eron Shosteck.
Some environmental
groups and Honda Motor Co. Ltd. (Tokyo:7267.T - News) have rebutted
those arguments, saying previous studies did not include the effect
of modern safety technology in crashes, and that size and design were
more important to safety than sheer mass.
David Friedman,
research director for the Union of Concerned Scientists Clean Vehicles
program, said the study did not account for the fact that lighter vehicles
tend to be cheaper, smaller and sold with fewer safety features.
"The fundamental
problem with this study, and the same problem they've had before, is
it's not looking at weight reduction. It's looking at design changes,"
Friedman said. "There's a lot of technology you're giving up with
this weight reduction."
DOES HEAVY MEAN
SAFE?
The NHTSA study
looked at cars and trucks built between the 1991 and 1999 model years
that were involved in fatal crashes between 1995 and 2000. It analyzed
two weight classes of cars and trucks, and then estimated how the fatality
rates might have changed had the vehicles weighed 100 pounds less.
In three of the
four groups -- both car groups and trucks weighing less than 3,870 pounds
-- it found deaths in crashes would have increased from 2 percent to
4.3 percent, with the highest increase for light cars.
For trucks weighing
more than 3,870 pounds, NHTSA said the increase was not statistically
significant. NHTSA said its researchers adjusted the data to account
for differences in driver age and gender, rural versus urban driving
and other variables such as night driving.
"What I would
hope that this report does is put to rest any nonsense ... that you
can build small, lightweight cars that are just as safe as heavier vehicles,"
said Adrian Lund, the chief operating officer for the Insurance Institute
for Highway Safety. "Clearly, physics make a difference."
Vehicle weight had
been a central argument in last year's debate over tougher fuel economy
standards for trucks. The average weight of cars and trucks sold in
the United States has been rising in recent years -- with a corresponding
drop in average fuel economy -- as consumers opted for larger and more
luxurious vehicles.
Many automakers
have long argued that if fuel economy requirements rise too quickly,
the only way to meet them is by drastically cutting vehicle weight.
When it raised the standards this year, NHTSA said it believed automakers
would not need to cut weight to meet the tougher rules.
But Friedman said
the study's own calculations for the death rates in accidents by vehicle
type contradicted such conclusions. For example, in vehicles built between
1996 and 1999, NHTSA found mid-size SUVs had higher death rates for
drivers than small SUVs or mid-size passenger cars.
"What I fear
is this study for many is going to reinforce the fallacy that weight
determines safety. And that's not good information for consumers and
that's not good information to base policy on," he said.
