A 250-tonne casting of molten glass took place on a furnace in a factory manufacturing hollow glass following perforation of a refractory block in the vicinity of the siphon at the base of the 1st tank block. The intervention of plant employees, combined with the deployment of fire nozzles plus the shutdown of machinery and the workshop’s electrical installations, prevented ignition of the site’s buildings. The casting operation was completed 2 hours after the arrival of fire-fighting teams. All glass had remained within the retention facility associated with the furnace. The hydraulic system was kept on until the next morning. Since internal lift pumps had gradually been obstructed by glass fines, a specialist pumped the cooling water that had accumulated in the basement and discharged it into the factory’s containment basin. This water quantity (50 m³) was subsequently treated at the site’s wastewater plant. Wear of the refractory block at the low point of the furnace, at the end of its life cycle phase, caused this accident. The furnace was then definitively shut down, given that completion of its useful operating life had been scheduled within the upcoming 3 months. No redundancies had to be announced, but the factory proceeded with planned layoffs.