In a refining station of an electric steel plant, an explosion ripped through a dome covering a ladle containing 240 t of molten steel. Seven workers were injured, including one who was seriously injured and had to be evacuated. The station and control room were extensively damaged. Production operations had to be shut down. A rupture of a donut-shaped cooling ring (an elliptical perforation measuring 15 x 7 cm) at the base of the arch of the refining station resulted in an influx of water into the molten steel causing the explosion. Damages were evaluated at 0.6 MF and operating losses at 29.3 MF.