Changes to Underride Guards Sought as Study Finds U.S. Standard Inadequate

This story appears in the March 7, 2011, print edition of Transport Topics. Click here to subscribe today.

The federal standard for underride guards on trucks and trailers is inadequate and should be upgraded to protect the drivers of vehicles that crash into the rear of trucks, an insurance safety advocacy group said last week.

The Insurance Institute for Highway Safety made the claims, citing test crashes that showed the guards can “buckle or break away from their trailers — with deadly consequences” when hit by cars.

The institute, funded by insurance companies that write 80% of the automobile policies in the United States, also asked that all large trucks and trailers be required to have the guards, which are supposed to keep cars from “underriding” — i.e., sliding underneath the vehicle — if they hit the back of a truck or trailer. Some trucks currently are exempt from the rule, the group said.

The IIHS filed a petition Feb. 28 with the National Highway Traffic Safety Administration, which sets the standard for underride guards.

NHTSA already was looking at ways to strengthen the safety standard for the guards, according its administrator, David Strickland.

“In 2009, NHTSA identified underride performance in rear-corner impact crashes as a part of the current standard that needed improvement, and today’s IIHS report is consistent with our findings,” Strickland said in a statement.

On March 1, the IIHS published the results of crash testing it conducted last year on guards that meet the current U.S. standard, as well as the Canadian standard, which the institute said is more exacting.

In a televised interview March 1, Bill Graves, president of American Trucking Associations, said there is “clearly a step that needs to be taken” to address underride guards.

“What the federal government thought was adequate a number of years ago, when these specifications were developed, is probably not adequate today,” Graves said.

The federal government first required guards on trucks in 1953. A 1998 upgrade to the standard did not make the guards strong enough, the institute said. And not all trucks are required to have the guards, an exception that includes pole trucks and low-chassis trucks.

“As a result of NHTSA’s 2009 review, the agency initiated an in-depth field analysis to determine how we can improve current federal motor vehicle safety standard requirements. We expect to complete our review in 2012,” Strickland said.

NHTSA data show that, in 2009, there were 319 traffic fatalities among occupants of cars that crashed into the rear of trucks or trailers.

ATA spokesman Sean McNally said ATA sees the institute report as a first step in tackling the underride issue, but additional study is needed.

It is more important to prevent accidents in the first place “because even the best underride guards will not prevent a single crash,” McNally said.

Adrian Lund, president of IIHS, said in a statement that a car’s front-end design may earn top marks for minimizing injuries in some crashes, but hitting the back of a large truck is a “game-changer.”

Underriding the back of a truck or trailer makes “death or serious injury more likely since the upper part of the passenger vehicle’s occupant compartment typically crushes as the truck body intrudes into the vehicle safety cage,” he said.

The Canadian standard for such guards is higher in terms of strength and energy absorption, according to the group.

However, the crash testing showed that even the more exacting standard is still “not strong enough or comprehensive enough to prevent underride in crash configurations that cause many severe injuries.”

In the testing, a 2010 Chevrolet Malibu was crashed into the rear of parked trailers, sometimes hitting the middle of the underride guard, and sometimes hitting at an angle.

Trailers used for the tests were manufactured by Hyundai Trans-lead, a subsidiary of Hyundai Motor Co., San Diego; Wabash National Corp., Lafayette, Ind.; and Vanguard National Trailer Corp., Monon, Ind., a subsidiary of China International Marine Containers Ltd.

Hyundai Translead’s guards met the U.S. standard. The Wa-bash National and Vanguard National guards met both the U.S. and Canadian standards.

Vanguard National declined to talk about the institute’s report.

Tom Rodak, Wabash’s director of corporate marketing, said his company “designs and tests the safety performance of the trailers we manufacture to ensure they meet, if not exceed, government highway safety regulations.”

Glenn Harney, chief sales officer for Hyundai Translead, said on March 1 he had not yet read the institute’s report.

“Clearly, we are anxious to have the IIHS share their data with us and compare their findings to our own,” Harney said. “It is such a complex issue, we need to work closely with anyone who has testing that is different from ours.”

Harney also said Hyundai offers “a Canadian-certified rear underride guard,” but that the institute testing involved only Hyundai’s 2007 model, which was designed to meet the U.S. standard.