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U.S. Department of Transportation U.S. Department of Transportation Icon United States Department of Transportation United States Department of Transportation

The Role of Human Factors in Cargo Tank Rollovers


To evaluate/constructively shape the human factors that play a role in cargo tank rollovers.


In previously completed Agency research on cargo tank rollovers, driver error was identified as the primary cause of the rollover 78 percent of the time. An analysis of Police Accident Reports determined that little can be determined from the crash data. A National Highway Traffic Safety Administration (NHTSA) study reported that, “Results for injury and property damage indicated that 88.5 percent of crashes are not associated with rollover or loss of control. The odds of rollover increase as cargo weight increases, but loss of control and cargo weight appear independent. The odds of rollover were about 2.6 times greater for cargo weight in the 5,001–20,000 lb category compared to the 0–5,000 lb category. The ratio increases to 7.4 when comparing the heavy category to the light category. For loss of control, the comparative odds ratios were 0.9 and 1.0, respectively, suggesting no association between loss of control and trailer cargo weight. The odds of rollover were 2.6 times greater on ramps than in other locations, and the odds of loss of control on straight sections of road were 2.2 times greater. Tank trailers were much more likely to roll over than van trailers. The odds ratio is approximately 3.5. For loss of control, the association was not as strong, but the odds of loss of control were 1.8 times greater for tanks compared to vans.”


This research seeks to obtain opinions from a wide range of carrier experts (from carriers with excellent safety records) on best practices for preventing rollovers. This includes discussion of topics such as a driver’s behavior and health, carrier safety culture, dispatching practices, fatigue management, etc. Study findings will be used to support recommendations for development of online training to promote adoption of best practices for avoiding cargo tank rollovers.


A report identifying the best practices for addressing human factors in cargo tank rollovers and recommendations on how the Agency could proceed to develop an online training curriculum to promote these best practices.



August 2016: Phase I awarded
April 2017: Phase II awarded
October 17, 2017: Updated project work plan
June 2018: Develop a draft proposed curriculum and present it at a National Tank Truck Carriers (NTTC) Safety conference


FY16 Funding: $100,000
FY17 Funding: $100,000

Current Status:

Project completed.

Project Manager:

For more information, contact Nicole Michel of the Research Division at


Pipeline and Hazardous Materials Safety Administration