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Safety Recommendation Details

Safety Recommendation H-14-003
Synopsis: These recommendations address four topics: (1)mitigation of blind spots to protect passenger vehicle occupants, pedestrians, cyclists, and motorcyclists from being struck when drivers of tractor-trailers fail to detect their presence; (2)protection of passenger vehicle occupants from being injured as a result of underriding the sides of tractor-trailers; (3) protection of passenger vehicle occupants from being injured as a result of underriding the rears of trailers; and (4) improving traffic safety data concerning trailers involved in crashes. The NTSB is issuing seven safety recommendations to NHTSA regarding the safety of tractor-trailers.1 Information supporting these recommendations is discussed below.
Recommendation: TO THE NATIONAL HIGHWAY TRAFFIC SAFETY ADMINISTRATION: Require that newly manufactured truck-tractors with gross vehicle weight ratings over 26,000 pounds be equipped with side underride protection systems that will reduce underride and injuries to passenger vehicle occupants.
Original recommendation transmittal letter: PDF
Overall Status: Open - Acceptable Response
Mode: Highway
Location: Washington, DC, United States
Is Reiterated: No
Is Hazmat: No
Accident Reports:
Report #: None
Accident Date: 5/17/2011
Issue Date: 4/3/2014
Date Closed:
Addressee(s) and Addressee Status: NHTSA (Open - Acceptable Response)

Safety Recommendation History
From: NTSB
Date: 11/13/2017
Response: We note that you are researching the effectiveness of side guards in preventing vehicle underride. Pending the recommended protection system requirement for both trailers and truck tractors, Safety Recommendations H-14-2 and -3 are classified OPEN--ACCEPTABLE RESPONSE.

From: NTSB
Date: 5/7/2015

Date: 5/6/2015
Response: -From Mark R. Rosekind, Ph.D., Administrator: NHTSA completed a two-year research program with the University of Michigan Transportation Research Institute (UMTRI) to collect and analyze crash data on rear underride in fatal truck crashes. The study was expanded to analyze the incidence of side underride crashes through a clinical review of cases in the Large Truck Crash Causation Survey. The UMTRI evaluation recorded the occurrence of a light vehicle underriding the side of a cargo body or trailer in 52 of the 411 cases. However, the full dynamics of the crash event were unknown, and a full crash investigation was not performed. In response, the agency recently completed a more detailed analysis of the cases and determined that additional research was warranted. In 2015, NHTSA is planning a research study to evaluate the efficacy of side underride guards in preventing vehicle underride into heavy trailers. Specifically, the agency is looking into how side guard designs (of reduced weight) may assist in reducing underride relative to passenger car orientation, speed and impact location. Upon completion of this study, we will make a determination as to whether there is a need to regulate side underride guards, or whether further research is warranted. Factoring into this decision will be information about cost and weight. A recent SAE International paper, 2014-01-0565, estimated the weight of side underride guards for trailers to be 853 pounds.