NTSB report suggests overheated wheel bearing may have derailed toxic train in Ohio

Federal investigators on Thursday released a highly anticipated preliminary report about the February 3 derailment of a train carrying hazardous materials in East Palestine, Ohio, where residents are now worried about health and environmental effects.

Norfolk Southern Railway’s (NS) train 32N featured two head-end locomotives, a distributed power locomotive, and 149 railcars—20 of which were transporting combustible liquids as well as flammable liquids and gas, including vinyl chloride.

Thirty-eight cars derailed, including 11 containing hazardous materials “that subsequently ignited, fueling fires that damaged an additional 12 non-derailed railcars,” according to the new National Transportation Safety Board (NTSB) report. Amid fears of an explosion, crews conducted a “controlled venting of the five vinyl chloride tank cars.”

While the release of hazardous materials and its short- and long-term impacts on residents and the region have garnered national attention—and the U.S. Environmental Protection Agency this week ordered Norfolk Southern to pay for cleaning up contaminated soil and water—the NTSB’s four-page report has put focus on a potential cause of the derailment: a wheel bearing failure.

Citing Allan Zarembski, director of the Railway Engineering and Safety Program at the University of Delaware, The Washington Post reported Thursday that “an overheated bearing is perhaps the most common cause of a failed axle in a derailment.”

“In recent years,” the newspaper added, “railroads—including Norfolk Southern—have added sensors on tracks that measure the temperature of bearings to determine whether overheating could pose a derailment risk.”

Train 32N, which Norfolk Southern workers say they knew was unsafe, passed three hot bearing detector (HBD) systems—designed to detect overheating and provide audible real-time warnings to crews—before it derailed, the NTSB report says. At milepost 79.9, the suspect bearing from car 23 was 38°F above ambient temperature; at milepost 69.01, it was 103°F; at milepost 49.81, it was 253°F.

NS crews are supposed to stop and inspect potential problems when alerts indicate that there is “a difference between bearings on the same axle greater than or equal to 115°F,” or there is a bearing between 170°F and 200°F, the publication notes. If the recorded temperature is greater than 200°F, the instruction is to “set out” the railcar.

In this case, the HBD system at milepost 49.81 “transmitted a critical audible alarm message instructing the crew to slow and stop the train to inspect a hot axle,” the document details. “The train engineer increased the dynamic brake application to further slow and stop the train. During this deceleration, an automatic emergency brake application initiated, and train 32N came to a stop.”

“After the train stopped, the crew observed fire and smoke and notified the Cleveland East dispatcher of a possible derailment,” the report continues. “With dispatcher authorization, the crew applied handbrakes to the two railcars at the head of the train, uncoupled the head-end locomotives, and moved the locomotives about 1 mile from the uncoupled railcars. Responders arrived at the derailment site and began response efforts.”

The report was put out as U.S. Transportation Secretary Pete Buttigieg visited East Palestine—the day after an appearance there from former President Donald Trump, who is seeking the GOP’s 2024 presidential nomination and whose administration rolled backback Obama-era rail safety regulations.