It is fairly clear that an overheated wheel bearing caused the catastrophic train derailment in NE Ohio. Pictures showed sparks emitting from the train for about an hour before the crash. I worked on instrumenting truck weigh stations, and infrared sensors were used to detect overheated wheel bearings. Truckers thanked the station crew for saving their lives.

Such sensors are cheap and should be deployed along every railroad track that carries hazardous materials. Placing them about 30 minutes apart (depending on train speed) would detect such issues before they become fatal.

Now they say there was a sensor that detected the overheating, but the threshold may have been set too high. The train was trying to stop.