An explosion occurred on a zone dedicated to destroying pyrotechnic products. The bags containing pyrotechnic waste (fouled packaging and rags) were planned for destruction without first being opened. They contained a quantity of explosives in excess of the designated limit, which caused shortly after ignition inside the furnace a violent reaction comparable to the detonation of 0.5-2 kg of TNT. Technicians were sheltered offsite and did not sustain any injuries. The site furnace was seriously damaged: a crater was formed in the ground, a door was thrust a distance of 40 m, roof gratings were damaged, etc. The operator verified the waste sorting procedure and provided personnel with additional training; moreover, the operating protocols for waste destruction preparation steps were all updated.