By James R. Heale
Imagine a seat that flimsy
in the third row, inches from the rear glass, as in today's sport-utility
vehicles and car-SUV crossover models. The kids are buckled up back there,
you're stopped at a light - and a drunk doesn't notice and rear-ends you
at 30 or 40 or 50 miles an hour. The result is frightening to contemplate.
Chances of that happening are
growing fast because third-row seats have become a must-have feature in
millions of vehicles. To meet customer demand, third rows are being squeezed
wholesale into both SUVs and crossovers barely long enough to accommodate
them, leaving mere inches between the seat and the back of the vehicle.
Distance isn't the only criterion
for judging the safety of third seats; seat strength and design are key.
But every one of those seats is governed by a 32-year-old federal strength
and safety standard that won't be changed for at least a year.
Birth of a Trend
Watershed year for third-row seats was 1997: Dodge offered midsize, midprice
Durango with a third row, and Mercedes-Benz put one in its upscale ML
Previously, third rows were
for minivans and big SUVs.
Now, when third-row seats are
offered, they're taken. For example, 96% of Durangos had three rows last
If seating is the question,
aren't minivans the answer? "I hate minivans. I'd never in a million
years have a minivan," says Linda Steinberg of St. Louis, speaking
for thousands of minivan defectors.
But "when people started
turning away from minivans, they wanted SUVs to do everything their minivans
did," says George Peterson of consultant AutoPacific.
"The third row is pretty vulnerable to rear-enders - like about twice
as dangerous" as other rows, says safety consultant Mike
Brownlee, formerly in charge of defect investigations and rules compliance
for the National Highway Traffic Safety Administration (NHTSA). As more
third-row seats hit the market, injuries and deaths will increase, he
Seat safety has been under
fire for more than a decade. The proliferation of third-row seats, mainly
meant for kids, gives the complaints new vigor.
lawn chair could pass" the NHTSA minimums, says Kevin
Calcagnie, a Newport Beach, Calif., lawyer who has sued car companies
over seat-related injuries.
Ford Motor's director of safety
research, Priya Prasad, won't buy that, but he did provide the big-guy-squirming
example of what could overwhelm a seat no stronger than the feds require.
13 Years and Not Done
NHTSA plans to propose seat-standard
upgrades this summer - 13 years after the agency began its official rule-change
process in response to requests from safety experts. It'll take at least
a year to collect public and industry comments and fashion a new regulation.
The delay, NHTSA says, is proof of how complex the issue is, rather than
evidence of foot-dragging.
Here's the dangerous problem:
In a rear crash, the seat back - regardless of which row - acts as the
restraint system, just as the safety belt and air bag do in a front crash.
If a seat back is so rigid that it stays upright in a violent rear-ender,
the stiff seat slams its passenger forward at the moment of impact. Then
the passenger snaps backward against the stiff seat as the struck vehicle
halts. Severe whiplash can result.
If, on the other hand, the
seat is so yielding that it'll absorb lots of the crash force, the seat
back bends far enough backward that the passenger could fly out into whatever's
behind - solid glass or a tailgate, in the case of third-row seats.
The bounce-back from a yielding
seat also can cause whiplash. Plus, it takes close to 3 feet of space
for a yielding seat to lay back fully. A third row gets that much space
only in big SUVs, such as Chevrolet Suburbans.
The sweet spot is somewhere
between very stiff and fully yielding, but nobody's quite sure where.
There's no generally accepted crash-test dummy to measure rear impact
forces, and no universal rear-crash test to measure seat safety.
There were 2.3 million
rear collisions in 2000, according to the latest-available federal statistics.
That was 21.7% of all crashes. There were 2,980 fatal rear-end wrecks
in 2000, 6.2% of all fatal collisions.
The worst thing about a rear-ender
might be the driver's helplessness.
"A rear-end collision
is one you don't control. Somebody drives into you while you're sitting
at a light or something. In front, I can see what's coming and try to
avoid it," says Matthew Bernstein. He lives in Manhattan, drives
a crossover SUV with three rows, and calls it "a little nerve-racking"
because his kids are so close to the back.
A decade before third-row seats
became a must-have feature in SUVs and crossovers, they were merely a
practical accessory in minivans. Now there are millions
of minivans on the road with third-row seats, enough to generate
reliable accident data.
When a minivan with a
third-row occupant is hit from behind, the occupant is killed half the
time, according to
a Ford Motor analysis.
It's lucky, then, that third
rows are infrequently occupied - just 1% to 2% of the time, according
to accident statistics.
But when somebody is back there,
it's usually a child. Adults won't even fit many of the latest third-row
designs. Kids are least likely to be properly buckled up, studies show,
and correct use of the safety belt is key to surviving rear crashes, safety
experts note. Compounding the danger, today's third rows are pretty close
to the point of rear impact.
For example, GM's Buick Rendezvous,
a crossover SUV based on a minivan, has just 8 inches between the third-row
seat back and the tailgate glass. Ford's Explorer SUV has 13 inches. Honda's
Acura MDX has about a foot, depending on how the seat's adjusted. Suzuki's
XL-7 small SUV has about 13 inches of clearance, depending on the adjustment.
An extraordinarily well-designed
seat can help make up for lack of crush space. But there's more agreement
on what makes a good cup holder than what makes a crash-worthy seat.
"There is no litmus test.
It's largely judgmental," says Bob Lange, General Motors' executive
director of vehicle crash-worthiness. "There's no single evaluation
one can run that says, 'Yup, you got it.' There's a lot more art to it.
It's like Goldilocks - it has to be just right."
And "just right"
means different things to different automakers.
BMW Chairman Helmut Panke,
for instance, says that his marketing people have been lobbying for an
optional third seat for the BMW X-5 crossover SUV. But Panke says he hasn't
seen a design that he believes is safe, because the seat would be so close
to the rear of the vehicle.
Rival brand Volvo, on the other
hand, has a slightly bigger crossover SUV called XC90 coming late this
year with a third-row seat, and insists it is safe. "It was tempting
to put the third row farther back, but we have to have the crush space
for a high-speed (rear-end) crash," says Hans Wikman, XC90 project
"Whether there's 1 foot
or 3 feet in the rear, it comes down to the design," says Frank Paluch,
chief engineer at American Honda's research and development operation.
No Universal Design
In addition to disagreement
on how far back third-row seats safely can be placed, there's no universal
Ford's Prasad says most models
in the U.S. market have settled on about triple the NHTSA standard. NHTSA
requires a seat back to withstand 3,300 inch-pounds of force, a measure
of pressure equivalent to what 3,300 pounds could exert at the end of
a one-inch lever, or 1 pound could exert at the end a 3,300-inch lever,
or any combination of those that multiplies to 3,300.
In Prasad's earlier example,
a hefty driver pushing backward exerts more force than that. A safety
consultant's proposal to NHTSA 13 years ago suggested 56,000 inch-pounds.
"Everybody has migrated
to about 10,000 inch-pounds. The seat should not break if you are leaning
against it entering the car, or if you go into your hip pocket for your
wallet," Prasad says.
Lange says GM's standard is
"multiple times" the federal standard. Honda says its seats
are less than twice the federal standard, but safe because its vehicles
dissipate crash forces well.
Those are the closest to real
numbers that automakers provide. Car companies say their seats are safe
and exceed federal standards, but won't disclose the seat-strength numbers
to prove it.
NHTSA began looking into modifying
its seat-safety regulations in 1989 after separate petitions from safety
consultants Edward Harkey and Kenneth Saczalski, both focusing on seat
NHTSA's official position on
its long-running process: "There is genuine debate in the technical
literature regarding the risks and benefits of more-rigid seat backs vs.
those that yield, and we must ensure that any changes to the standard
are cost-beneficial without producing other safety problems. ... NHTSA
intends to issue a proposed upgrade to the seat back standard this summer."
The agency, in separate actions,
is toughening head-restraint regulations and fuel-system strength rules
before revising the seat standards. Proper head restraints will minimize
whiplash threats posed by stiffer seats, NHTSA believes. And fuel systems
that must not leak after 50-mph rear-enders, instead of 30-mph now, will
minimize fires, dangerous to people trapped inside because of flimsy seats.
Safety consultant Brownlee,
the former NHTSA official, says head restraints are key. "The company
line has been that you have to have forgiving seats. But the trick is
you have to have the seats and the head restraints acting in concert,
and then you're OK. The whole whiplash thing is a red herring," he
Without even an imperfect index
of seat safety, consumers have little but the chorus from car companies:
"Trust us; seats are safe."
Does that mean that people
in the back seat of GM's Buick Rendezvous, only inches from the back glass,
are as safe in a rear-end crash as those in the third row of GM's Chevy
Suburban, three feet from the back?
"Well," says GM's
Today March 1, 2002