Yesterday, the U.S. Department of Transportation (USDOT) repealed a May 2015 rulemaking that would have required the installation of electronically controlled pneumatic (ECP) brakes on certain tank cars, according to U.S. Sen. John Thune (R-S.D.). The USDOT had until Dec. 4 to publish a determination that the ECP rule either was justified or should be repealed.

The Federal Railroad Administration rulemaking had set a timetable for requiring ECP brakes on newer tank cars trains used to haul certain hazardous or flammable materials, such as ethanol and crude oil. ECP brakes issue electronic signals to simultaneously apply and release brakes throughout the length of a train instead of each car applying brakes individually —  a system the government considers more effective in emergency situations.

A provision in the Fixing America’s Surface Transportation (FAST) Act directed the National Academies of Sciences (NAS) to analyze the rule and reevaluate ECP braking results. In a report issued in October, NAS officials said the approach used to mandate ECP brakes over other technologies was incomplete and unconvincing, said Thune — who chairs the Senate Committee on Commerce, Science and Transportation — in a press release. NAS officials also could not conclude that ECP brakes’ emergency performance was superior to other braking systems, he said.

Moreover, a Government Accountability Office (GAO) study released in October 2016 found the UDOT’s justification for the rulemaking lacked transparency, said Thune. The FAST Act had required the GAO to conduct an independent evidence-based evaluation of ECP brakes.

“Repealing this rule puts sound science and careful study by the independent National Academies of Sciences and Government Accountability Office over flawed guesswork the [USDOT] used in 2015,” said Thune. “While new technologies offer potential improvement to railroad safety, regulators have a responsibility to fairly evaluate effectiveness and avoid arbitrarily mandating new requirements.”

The Association of American Railroads (AAR) had lobbied to repeal the rulemaking. AAR officials believe the widespread use of ECP brakes would not provide any meaningful safety benefits compared with existing braking systems, and that the brakes would impose very high costs on railroads for minimal safety benefits.