The Philadelphia Inquirer

PHILADELPHIA – Consumer Reports magazine on Thursday withdrew its Jan. 4 assertion that nine of 12 models of infant car seats “failed disastrously” when subjected to the crash tests that federal officials use to rate vehicles’ safety for adults.

The move came after the National Highway Traffic Safety Administration questioned the magazine’s methodology in one of two key tests. The agency said the magazine’s side-impact test subjected the seats to the equivalent of a broadside crash by a vehicle traveling at more than 70 mph, about twice as fast as Consumer Reports said it intended.

To doublecheck its own analysis, NHTSA put 11 of the 12 seats through its own version of Consumer Reports’ side-impact test. (The agency was unable to find one of the models the magazine reviewed.)

“All 11 passed with flying colors,” said NHTSA Administrator Nicole Nason.

Both NHTSA and Consumers Union, publisher of the nonprofit magazine, issued brief statements Thursday about the NHTSA’s test and the magazine’s decision to withdraw the car-seat report, which was removed from Consumer Reports’ Web site but appears in the February edition of the printed magazine.

Consumer Reports said it planned “further tests of the performance of those seats in side-impact collisions.”

It’s not clear what that new testing will show. The magazine’s initial report said seven of the 12 car seats also failed to adequately protect infant-sized dummies in its front-impact test.

“We didn’t have any questions about the way they conducted the front-impact tests,” Nason said. However, she said that when NHTSA re-created that test, meant to simulate a nearly head-on collision between two similar vehicles each traveling at 35 mph, “none of the seats separated from the bases” – one of the failures highlighted in Consumer Reports’ critique.

News of the magazine’s Jan. 4 findings left many car-seat users confused. “Parents were panicked,” said Nason, saying the report prompted more than 400 calls to the agency.

Monica Taylor of Fairmount, Pa., was among the worried. Her daughter was a few days old, and she was shocked at the poor performance reported for a seat the magazine had previously praised, the Britax Companion. Now she’s taking a wait-and-see stance.

“At the time, Consumer Reports said that was far and away the safest,” Taylor said.

Nason praised Consumer Reports’ quick response to NHTSA’s rebuttal.

“It was a significant error, but they took the right action to withdraw the report,” Nason said during an interview.

Others familiar with crash-test design were more critical.

“This is a very basic error – it’s an error that many of us, if we’re not thinking about the physics, could make,” said Adrian Lund, president of the Insurance Institute for Highway Safety, which also conducts vehicle crash tests. “But clearly, if you’re conducting tests and presenting them to the public, this is not the kind of error you should make.”

Lund said crash tests use varied methodologies that are designed to be comparable but that differ in ways that can sometimes be confusing.

NHTSA’s side-impact crash test certainly qualifies. It is designed to mimic the forces of collision in which a vehicle crossing an intersection at 17 mph is broadsided by a similar vehicle traveling at 34 mph.

To rate how sample vehicles and their occupants can withstand such forces, though, NHTSA’s testers do something different: They crash a barrier moving at 38.5 mph into a stationary test vehicle.

When Consumer Reports set out to see how infant seats would perform in such a crash, Lund said, it used its own test design, in which the infant seat is strapped onto a benchlike device called a “test buck.” The test buck is then mounted on a sled that is accelerated as if it were a car that had been broadsided.

Lund said Consumer Reports’ test failed to account for all the interactions of an actual crash.

He said a crash like those NHTSA uses to test side impacts would only cause the test buck to accelerate to about 18 or 19 mph. But he said Consumer Reports’ outside laboratory accelerated the test sled to about twice that speed – which Nason said was equivalent to a car’s being broadsided at about 70 to 80 mph.

“It’s extremely impressive that any of the seats held together,” Nason said.

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(c) 2007, The Philadelphia Inquirer.

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AP-NY-01-18-07 2041EST