Arc furnaces used for melting and refining steel generate large amounts of smoke and dust that can cause severe pollution in and around the furnace building unless a satisfactory depollution system is provided. This paper discusses a water analogue model study conducted at Neyrtec's Research & Test Centre to design an efficient furnace-pollution collection system in which the gas flow to be processed was optimized. The study showed that this flow could be 25–30 per cent lower than the value recommended by dust collection plant suppliers on the basis of standard design procedures. A fullscale collection system based on the design developed with the model has just been completed. The fullscale system confirmed the excellence of the collection efficiencies and the validity of the model results.