As more hazardous materials are shipped in High-Hazard Flammable Unit Trains, reducing the risks of transporting these materials by rail remains a top industry priority. Dr. Xiang Liu received the Outstanding Paper Award from the Committee on Transportation of Hazardous Materials (AT040) earlier this year for his recent research on this critical safety topic.
The position of hazardous material (hazmat) railcars in High-Hazard Flammable Trains (HHFTs) and the number of classification yards they pass through can impact the risk of derailment and hazardous material release.
In a recent paper CAIT researchers and their collaborators from the University of Texas at Austin, University of Houston, Applied Research Associates, Inc., and National Yang Ming Chiao Tung University in Taiwan, examined the risks of transporting Class 3 flammable liquids by tank cars — specifically comparing the risks between high-hazard flammable unit trains (HHFUT) and HHFTs for shipping hazmat.
Over the past decade, the Federal Railroad Administration and other organizations have adopted requirements and regulations defining certain trains transporting large volumes of flammable liquids as HHFT and others as HHFUT depending on their composition and what they are carrying. These rules are designed to reduce the risks associated with transporting large quantities of flammable liquids.
This paper, “Quantifying the Influence of Tank Car Position and Train Configuration on the Risk of Rail Transport of Class 3 Flammable Liquids,” was published in the Transportation Research Record in 2024 and compared the two types of trains considering both mainline and yard operations.
Dr. Xiang Liu, Associate Professor at Rutgers’ School of Engineering and Director of the Rail and Transit Program at the Center for Advanced Infrastructure and Transportation (CAIT), led the award-winning study as the Principal Investigator.
The researchers deployed a probabilistic risk analysis methodology to quantify the transportation risk in terms of total expected release consequence (i.e., casualties) given the total amount of Class 3 flammable liquids transported in HHFUT and HHFT configurations with different tank car placement strategies While this is a good start, Dr. Liu added that in future work the methodology can be extended to different operating scenarios to help the industry better understand the risks and impacts of train configuration and tank car placement when moving hazmat.
“The U.S. is home to the largest and most cost-efficient freight railroad network in the world,” said Dr. Liu. “Keeping this system running safely and smoothly is critical to economic success and to connecting people with essential goods. Research like this is needed to ensure the industry understands potential risks with transporting hazmat and learns new methods to counteract risks.”
During the Transportation Research Board Annual Meeting earlier this year, Dr. Liu was presented with the Outstanding Paper Award from the Committee on Transportation of Hazardous Materials (AT040). This is the second year in a row that the TRB AT040 committee has recognized Dr. Liu’s team with the Best Paper of the Year Award in the area of hazmat transportation.
Safety is a core focus of the Rail and Transit Program that Dr. Liu leads. In another project with NJ Transit, his team is deploying cameras equipped with Artificial Intelligence at light rail grade crossings in New Jersey to collect and analyze real-time video data of pedestrian and vehicle travel. This AI-powered monitoring system can rapidly parse through video data to detect, analyze, and categorize safety events and near-miss incidents.
Equipping rail grade crossings with these AI-powered technologies will allow NJ Transit to collect and analyze previously unattainable safety data such as near-miss incidents. This information will serve as the foundation for data-driven safety countermeasures that can help protect communities, reduce service delays, and enhance rail reliability.
Dr. Liu also represents Rutgers and the New York-New Jersey Region in the Federal Railroad Administration’s National University Rail Center of Excellence (NURAIL). The first-of-its-kind center is dedicated to developing the future workforce while advancing research that enhances the safety, efficiency, and reliability of both passenger and freight rail transportation. The NURAIL initiative is led by the University of Illinois Urbana-Champaign and consists of nine consortium partners including Rutgers.
