Overview
- Authorities said the fire was brought under control, confinement orders were lifted, and highway, rail and river traffic reopened after air monitoring found no toxic risk to residents.
- The Lyon prosecutor’s office launched a criminal investigation for involuntary injuries, tasking the DCOS and the labor regulator DDETS to determine causes and responsibilities.
- Officials updated the toll to six injured employees, including three gravely burned, and confirmed that one of the severely injured workers died on Tuesday.
- Elkem reported the explosion occurred in a separate pilot laboratory during a routine devolatilisation of hydrogen‑containing silicone oils, with hydrogen likely involved in the blast.
- The Saint‑Fons site is a Seveso high‑threshold facility previously hit by incidents, including a fatal 2016 fire and a reported hazardous leak earlier this year, and it underwent several inspections in late 2025.