Some of the valves on railroad tank cars designed to keep volatile, toxic chemicals from exploding were damaged in the Ohio derailment last month as the train burned, investigators said Thursday.
Melted aluminum from protective covers on the valves raised the risk that the devices could malfunction, the National Transportation Safety Board said in an update to its probe of the Feb. 3 wreck in East Palestine.
No one was reported injured, but the massive derailment has reverberated through national politics and raised new concerns about the safety of toxic materials being shipped on U.S. railroads.
