What happened

An explosion tore through the C air-separation train at Henan Coal Gas Group's Yima gasification plant. The final official toll was 15 people killed and 16 seriously injured, superseding early reports of 10 dead, 19 injured and five missing. Investigators found that oxygen-rich cryogenic liquid had leaked into the cold box's perlite insulation for weeks. The plant continued operating despite rising oxygen readings and a visible crack because its backup air-separation system was unavailable. Rapid vaporisation produced a perlite eruption and cold-box collapse, which ruptured a nearby 500-cubic-metre liquid-oxygen tank; the oxygen-rich release then intensified explosions and fire among surrounding combustible materials. Authorities classified the event as a major production-safety responsibility accident. The marker is deliberately placed at city level because a reliable public plant coordinate was not established in the reviewed sources.

When cited sources give different casualty, damage or spill figures for this event, they’re reported side by side above rather than merged into one number. See how confidence levels work.