At 9 a.m., 4 successive explosions with 2 – 3 seconds between each one occurred on a powder manufacturing plant.
The explosions destroyed two dryers, a building for the weighing and dosage of hunting powders and a reinforced concrete building (unused since the last world war and waiting for demolition). The shock wave had an impact on buildings outside the factory up to 1 km (mainly broken windows). The costs of the internal damage were evaluated at 3 M euros, those of external damage to 2.5 M euros.
The explosion luckily took place on a sunday, the factory was closed and no-one was hurt. Ageing cellulose nitrate and nitroglycerin propellants lost their stabilizer, and self-ignited. The fire transited into an explosion as they were stored in a confined area. The first explosion made other stored products explode. In all, 2.9 t of pure cellulose nitrate and 4.6 t of a mixture of cellulose nitrate, nitroglycerine and additives were involved in the accident.
The operator reduced the stored quantities and suspended powders productions, looking for alternative processes.