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NHTSA’s Proposal to Upgrade Rear Impact Crash Protection to Have a Significant Impact on Accident Litigation

Earlier this month, the National Highway Traffic and Safety Administration (“NHTSA”) issued a notice of proposed rulemaking aimed at upgrading standards for underride protection in trailers and semi-trailers. NHTSA is looking to make the standards more stringent to improve underride protection in higher speed crashes. Although many trailers currently sold would be compatible with this new more stringent standard, the annual estimated incremental cost to ensure compliance of every trailer and semitrailer in the U.S. is $13 million dollars.

There is universal agreement safer equipment is in the best interests of everyone on the roads. In addition, from a risk-management perspective, underride accidents can be some of the most significant accident litigation insurers and trucking companies are forced to deal with. If the speeds involved are high enough (also known as an excessive underride crash), a passenger vehicle rear ending a trailer can result in the rear of the trailer or semitrailer entering the passenger compartment of the vehicle causing serious injuries or death. In many of these accidents, the operator of the truck was doing nothing wrong, likely sitting in traffic or at a light, while the operator of the passenger vehicle was not paying attention to their surroundings. No matter what the relative fault of the parties with respect to causing the accident, these accidents are likely to lead to litigation against the trucking company, with the plaintiff arguing the rear impact guard was not compliant with standards or sustained unrepaired damage. In my experience, I have never encountered a “minor” underride case. More stringent standards will place an increased burden on companies to inspect and monitor their fleet to make sure they are compliant with standards. The failure to do so could be costly.

Read more in the full NHTSA release and see the below an article I co-authored concerning rear impact guard litigation and how fleets can manage the risk. The advice in this article will continue to be of vital importance in risk management.

[text_box title="The Underride Guard: Controversy and Protecting Your Company, In Transit, August 12, 2013, at 1 "] The Underride Guard: Controversy and Protecting your Company

Every trucking professional is aware of how important it is for drivers to be properly trained. Keeping a proper lookout and monitoring surrounding vehicles is essential to roadway safety. Unfortunately, proper training and safe driving habits alone may not be enough to avoid the inside of a courtroom after an accident. Imagine that one day your driver is traveling down the road, observing the rules of the road and monitoring the traffic around him. As he slows and comes to a stop for traffic, he feels a sudden impact from behind. The driver of a passenger sedan behind him, perhaps following too closely, fails to notice traffic slowing, and rear-ends the trailer at a high rate of speed. The passenger sedan comes to rest under the trailer and its driver appears seriously injured.

Unfortunately, many of the underride guards on trailers today are not strong enough to prevent vehicles from underriding trailers in high speed accidents. Even though the truck driver in our example did everything right, he and his company may be sued by the driver of the vehicle that rear-ended the trailer. This is especially true if the underride guard was visibly deteriorated or if it had been repaired or replaced in the past.

Injury Statistics
According to the National Highway Traffic Safety Administration (“NHTSA”), approximately 423 people die and 500 people are injured each year in passenger vehicle accidents after striking the rear of trailers. (Insurance Institute for Highway Safety, Underride Guards on Big Rigs Often Fail in Crashes; Institute Petitions Government for New Standard (March 1, 2011), available at Federal regulations on underride guards are designed to prevent cars from sliding under the rear of trailers, crushing the vehicle and exposing the occupants to serious risk of harm.

History of Underride Guard Regulations in the United States and Canada
Underride guards were not federally regulated until 1952. (NHTSA, The Effectiveness of Underride Guards for Heavy Trailers (October 2010), available at The original standards required underride guards, but did not specify any size or strength requirements. (NHTSA, 2010). Currently, underride guards manufactured after January 1998 are regulated by Federal Motor Vehicle Safety Standards 223 and 224, which apply to all vehicles with a gross vehicle weight rating of 10,000 pounds or greater. (NHTSA, 2010). Safety standard 223 outlines strength and energy absorption standards, while standard 224 regulates the size and shape of the underride guards.

NHTSA has recognized that “[t]he importance of careful attachment hardware material selection and attachment design cannot be overemphasized.” 61 Fed. Reg. 2004, 2136 (Jan. 24, 1996). It has declined, however, to require the use of a particular type of attachment material or set specific strength requirements for attachment materials because such specifications are virtually impossible in light of the many different possible underride guard and trailer configurations. NHTSA believes that adequate performance can be achieved through a number of different attachment methods and to attempt to anticipate how a particular manufacturer chooses to secure its underride guards would be impractical. 61 Fed. Reg. at 2013. This decision not to state specific requirements leaves manufacturers free to choose appropriate designs. 61 Fed. Reg. at 2013. According to NHTSA, testing has shown the importance of factoring in the strength of the attachment point when designing an underride guard, making the attachment hardware design dependent. 61 Fed. Reg. at 2013.

Insurance Institute Testing in 2010
These regulations have come under a significant amount of scrutiny in recent years because of the inability of some underride guards to prevent injuries to motorists and their passengers. In 2010, the Insurance Institute for Highway Safety (“Insurance Institute”) conducted a number of tests comparing the strength of three different underride guards on trailers manufactured in the U.S. and Canada. All of the underride guards tested complied with U.S. standards and two of the underride guards tested met the more stringent Canadian standards, which require underride guards that are 75 percent stronger than those in the U.S. (Lisa Stark, Truck Underride Accidents: Drivers Endangered When Cars Slide Under Trailers, (October 5, 2012), available at

In each test, a 2010 Chevrolet Malibu, known for its 5-star safety rating, was caused to collide with the rear of the trailers at 35 MPH. In the first test, the Malibu struck each trailer squarely from behind. This pure frontal impact test revealed that trailers manufactured under the Canadian standards were more successful in preventing an underride accident than the trailers manufactured pursuant to American standards. The Insurance Institute also performed some additional tests where the Malibu did not strike the trailer directly from behind but instead the impact was offset to one side of the trailer. All of the underride guards, even those manufactured to the Canadian standards, performed poorly when the impact from behind was indirect, making this type of accident even more likely to result in injury.

The testing by the Insurance Institute, as well as figures on the amounts of deaths and injuries occurring in underride situations, have led to escalating calls for increased strength regulations for underride guards. In a 2011 interview with ABC News, a spokesman for NHTSA stated that “it is well aware of the scope and severity of the truck underride issue.” Stark, supra. However, no action was promised. As the calls for reform grow it will be up to NHTSA to determine if and when to issue new standards.

Actions Motor Carriers Can Take to Help Reduce the Severity of Rear Impacts
As demonstrated by the testing conducted by the Insurance Institute, the present design of underride guards is a work in progress. Until such time as more stringent regulations are created in the United States and Canada, rear underride guard accidents will continue to occur. However, there are steps motor carriers can take to reduce the severity of rear impacts.

One method centers around prevention maintenance. During regular audits of fleet vehicles, checks should be performed on the entire structure of the underride guard. Loose or missing bolts should be noted. Deformities to the frame which result from accidents should be noted. Rust and corrosion to bolts and frame pieces should be monitored. All of these forms of damage and wear contribute to the degradation of the underride guard’s strength and reliability.

NHTSA rules require damaged underride guards to be restored to “like-new” condition. This means that the manufacturer of damaged underride guards should be contacted to ensure that proper repairs are made to bring the underride guard back to an essentially new condition. Short cuts, such as re-using original bolts after they have been damaged, should not be taken. Another common problem involves bent frame members, which necessitates either total replacement or the proper calibration tool to bring the members back to their original shape and position. Often times, proper maintenance requires repair kits from the manufacturer and direct consultation with the trailer manufacturer.

In summary, although underride guards cannot prevent all accidents, if serviced and maintained properly, they may reduce the risk of many severe injuries and deaths. In order to best ensure compliance with appropriate regulations, it is incumbent on motor carriers to employ a safety audit program which specifically monitors the wear and tear on underride guards, and returns them to “like-new” condition per the instructions of the manufacturer. These actions will help to reduce the severity of rear impacts and possibly save lives, while at the same time lowering motor carrier risk from these types of accidents. 

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