BTS: Nearly Half of Tank Cars Carrying Class 3 Flammable Liquids Met New Safety Requirements

Tank cars move through Marietta, Ga., on July 20, 2015. (Photo by Todd DeFeo)

Nearly half (48 percent) of rail tank cars carrying Class 3 flammable liquids in 2019 met new safety requirements, up from a third (33 percent) in 2018.

That’s according to Fleet Composition of Rail Tank Cars Carrying Flammable Liquids: 2020 Report from the U.S. Department of Transportation’s Bureau of Transportation Statistics.

The report, measuring industry-wide progress in manufacturing and modifying rail tank cars that transport flammable liquids, has been submitted to Congress. This report tracks the fleet’s transformation carrying class 3 flammable liquids to be a fleet of DOT-117s, which meet new safety requirements.

Some class 3 flammable liquids are currently carried in rail tank cars, such as DOT-111s, which have fewer safety features. Federal officials expect the transformation of the fleet to be complete by 2029.

For crude oil alone, 73 percent of the tank car fleet in 2019 consisted of DOT-117s, up from 46 percent in 2018.

Non-jacketed DOT-111s, which do not meet the new safety standards, have not carried crude oil since 2016, and the percentage of all other tank car types hauling crude oil dropped from 66 percent in 2017 to 28 percent in 2019. DOT-111s were required to stop carrying crude oil in 2018.

Non-jacketed tank cars lack a layer of insulation and/or thermal protection between the tank shell and jacket that stabilizes the liquid’s temperature in the tank car and reduces the conductivity of heat from outside sources to the contents of the tank car. Non-jacketed DOT-111s are in the process of being phased out of the fleet of tank cars carrying Class 3 flammable liquids and will be completely phased out by 2029.

The report describes tank car safety upgrades’ progress from 2013 through 2019 by tank car type and flammable liquid type. Class 3 flammable liquids most commonly include crude oil, ethanol, and refined petroleum products.

In 2019, 112,685 rail tank cars were used to carry Class 3 flammable liquids, nearly as many as the 2015 fleet of 113,045 rail tank cars. In 2015, only 3 percent of the cars carrying crude oil and other Class 3 flammable liquids consisted of the DOT-117s, which meet the new safety standards, compared to 48 percent in 2019.

Survey results indicate that 7,938 DOT-117 and DOT-117R tank cars are projected to be built or retrofitted in 2020.

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