During a March 6 hearing, National Transportation Safety Board Chair Jennifer Homendy told the Senate Commerce Committee that the board’s examination of the February 2023 East Palestine, Ohio, derailment raises serious questions about the decision to conduct a controlled burn of tank cars containing vinyl chloride.
Homendy said shipper OxyVinyls was on scene and repeatedly advised contractors and responders that polymerization — the runaway chemical reaction Norfolk Southern’s contractors cited as their justification — was not occurring. "OxyVinyls informed them that polymerization was not occurring and there was no justification to do a vent‑and‑burn," Homendy said. Temperature monitors, she said, showed cooling and stabilization hours before the decision to vent and burn.
The chair characterized the contractors’ assessment as lacking the scientific basis necessary to justify an explosive mitigation action and said the on-scene decision makers were not always provided full information from the shipper. "They did not have that scientific background to address that," Homendy told the committee. That, she said, undercut the rationale given to incident commanders and state officials.
Committee members described the findings as extraordinary and troubling. Senator Vance said the evidence suggests on-site personnel provided incomplete or inaccurate information to local leaders and residents and raised the possibility that decisions prioritized operational or timeline considerations rather than available science. Members signaled legislative follow-up and additional oversight to ensure incident commanders and communities get comprehensive technical input when responding to hazardous-material incidents.
Homendy said the NTSB’s docket documents the shipper’s on-site communications, recorded temperature data and the board’s interviews with contractors and emergency personnel. She said NTSB staff will continue its factual and cultural safety reviews and provide more detailed findings into the record.