On Thursday, the NTSB released its preliminary report on the derailment of a Norfolk Southern train carrying toxic chemicals on Feb. 3 and the subsequent release of hazardous materials.

The report states that the NTSB identified the 23rd railcar as the first to derail, noting that a “surveillance video from a local residence showed what appeared to be a wheel bearing in the final stage of overheat failure moments before the derailment.”

Speaking to the press yesterday, NTSB Chair Jennifer Homendy apologized to the East Palestine community for the “devastating” event and stated that it was “100% preventable,” adding, “We call things accidents. There is no accident; every single thing we investigate is preventable.”

Homendy stated, “The critical threshold as per Norfolk Southern is above 200 degrees ambient. Upon passing the 3rd detector with a temperature of 253 degrees [Fahrenheit] above ambient … a critical alarm sounded, instructing the crew to slow down and stop the train to inspect the hot axle and if warranted to set car no. 23 out.”

As the investigation continues, the NTSB will “focus on the wheelset and bearing; tank car design and derailment damage; a review of the accident response, including the venting and burning of the vinyl chloride; railcar design and maintenance procedures and practices; NS use of wayside defect detectors; and NS railcar inspection practices.”