PHMSA urges tank car owners to upgrade fleets to DOT-117s

The Pipeline and Hazardous Materials Safety Administration (PHMSA) yesterday issued a safety advisory to DOT-111 tank car owners and shippers of flammable liquids to voluntarily upgrade their tank car fleets to the newest and safest available design, the DOT-117 tank car.

The safety advisory — issued in coordination with the Federal Railroad Administration — was prompted by the Feb. 3 Norfolk Southern Railway derailment in East Palestine, Ohio, PHMSA officials said in the safety advisory.

Data from the U.S. Environmental Protection Agency shows that 16 DOT-111 tank cars — some of which were carrying flammable gases and liquids and combustible liquids — were involved in the derailment and subsequent fire. Seven of those tank cars experienced head and/or shell breaches, with three cars releasing contained hazardous materials. Another three DOT-111 tank cars that were not carrying hazardous materials also released product, two through the bottom outlet valves and one through a leak in the top fittings.

Three DOT-117 and six DOT-105 tank cars were involved in the derailment, PHMSA officials said. Only one of them, a DOT-117 tank car carrying petroleum lube oil, released any product as a direct result of the derailment. The contents were nonhazardous.

The DOT-111 tank car design has a lower ability to survive derailments and fires without releasing its contents compared to current tank car designs, PHMSA officials said.

The concern over DOT-111 tank car survivability during derailments has been recognized for more than a decade. In 2011, the Association of American Railroads published an update to their tank car design standards, known as CPC-1232, that called for upgrades to DOT-111 tank cars built for use with flammable liquids, specifically petroleum crude oil, alcohols and ethanol and gasoline mixtures. The CPC-1232 called for safety features missing from the DOT-111 design, including a metal jacket, head protection, a thermal protection system, top-fitting protection and the use of bottom outlet handles that could be removed or would not activate in derailments.

In 2015, PHMSA and FRA published a final rule that created a new tank car specification, DOT-117J, to address the safety deficiencies of the DOT-111s. The DOT-117J includes safety features similar to AAR’s CPC-1232. The rule also created a pathway to retrofit existing DOT-111 tank cars to the DOT-117 standard, known as DOT-117R.

"PHMSA believes that it is possible, and in the clear safety interest of the public, for tank car owners and shippers using DOT-111 tank cars to acquire the DOT-117J, or even DOT-117R, specification tank cars," PHMSA officials wrote in yesterday's safety advisory.

PHMSA and FRA may take additional action if the National Transportation Safety Board’s investigation of the East Palestine derailment reveals the need for further regulation, they added.