|May 16, 2014|
Previously published on May 14, 2014
On April 3, 2014, the National Transportation Safety Board (NTSB) provided seven safety recommendations to the National Highway Traffic Safety Administration (NHTSA) addressing tractor trailer safety. The recommendations comprise four general topics:
- Mitigation of blind spots to protect passenger vehicle occupants, pedestrians, cyclists and motorcyclists
- Protection of passenger vehicle occupants from being injured as a result of their vehicle underriding (sliding under) the container of a tractor trailer during a side impact
- Protection of passenger vehicle occupants from being injured as a result of their vehicle underriding the rear of a tractor trailer
- Improving traffic safety data concerning trailers involved in crashes.
The NTSB stated that blind spots exist on the front, sides and rear of a tractor trailer. It stated further that the blind spot on the right side of the tractor trailer is of particular concern because it impinges on a large portion of the driver’s field of view and is disproportionately involved in collisions involving pedestrians, cyclists and passenger vehicles. The NTSB discussed three potential countermeasures to mitigate blind spots, including enhanced mirror systems, advanced technologies to detect vehicles in road-users’ blind spots, and specific technologies to alert tractor trailer drivers to other vehicles traveling in their blind spots. The NTSB recommended that the NHTSA require that newly manufactured tractor trailers with gross vehicle weight ratings (GVWRs) of more than 26,000 pounds be equipped with visibility enhancement systems, such as side view assistance systems with sensors that monitor blind spots after the driver engages his turn signal and rear cameras on the back of the trailer to help the driver see behind his trailer during reverse maneuvers.
Side Underride Protection Systems
The NTSB stated that side impacts constituted 15 percent of fatal two-vehicle collisions between large trucks and passenger vehicles during 2011, more than 15,000 injuries from 2001 to 2003 and 43,629 collisions from 2005 to 2009. The NTSB stated that side underride collisions are a serious safety problem because they defeat crumple zones, prevent air bag deployment and can compromise a vehicle’s safety cage. The NTSB recommended that the NHTSA require newly manufactured trailers with GVWRs of more than 10,000 pounds to be equipped with side underride protection systems. It also recommended that the NHTSA require that newly manufactured truck-tractors with GVWRs of more than 26,000 pounds be equipped with side underride protection systems.
Rear Underride Protection Systems
The NTSB stated there were 15,329 collisions where passenger vehicles collided with the rears of tractor trailers from 2005 to 2009; that these types of collisions constituted 19 percent of fatal two-vehicle collisions in 2011; and from 2008 to 2009, 633 fatal accidents involving tractor trailers were rear-end collisions. The NTSB indicated that during a rear-end collision, rear underride may occur. Similar to side underride, a rear underride can defeat the safety features of a passenger vehicle. The NTSB noted that the NHTSA promulgated a rule effective in 1998 strengthening rear underride guards, but the NTSB reported that studies have shown the limited effectiveness of rear underride guards required by the 1998 rule. The NTSB recommended that the NHTSA revise requirements for rear underride protection systems for newly manufactured trailers with GVWRs of more than 10,000 pounds.
Crash Data for Trailers
The NTSB indicated that while most collisions involving tractor trailers consisted of side and rear impacts to trailers, police reports provide less information for trailers than other types of motor vehicles. It noted that few accident report forms include spaces for trailer VIN or license plate numbers. The NTSB stated that trailer data is essential because of the number of collisions involving the trailers and because it would allow for a more efficient analysis of safety regulations. The NTSB recommended that the NHTSA add trailer VIN number and model year to the fatality analysis reporting system for trailers with GVWRs of more than 10,000 pounds and that the NHTSA work with the Model Minimum Uniform Crash Criteria Guideline expert panel to include the trailer license plate and VIN numbers in the next edition of MMUCC Guideline: Model Minimum Uniform Crash Criteria.
Additional safety regulations are likely to result from the NTSB’s recommendations. New tractor trailers probably will be outfitted with additional equipment to keep other drivers, pedestrians and cyclists safe. Following an accident, owners of tractor trailers that are not compliant with the new safety rules may face arguments asserting that if the driver and/or company merely had updated their tractor trailer, people might not have been injured.
Additionally, the increase in the collection of data by police about trailers involved in accidents will help the NTSB, NHSTA and others develop more analysis about accidents involving trailers. Increased scrutiny of trailers may in turn drive additional changes in the safety of trailer design and the impact of trailers on highway safety.