An explosion occurred at 9:25 am inside one of a silo’s 6 metal cells, which had been filled with 1 tonne of corn starch. No injuries were reported and property damage was minor (burnt filtration sleeves); the vents located on the upper part of the container shell were left open. During the deflagration, the 200-m³ volume cell (content: 110 tonnes) had been simultaneously in an emptying phase in the direction of the neighbouring enclosure and in a filling phase from the pneumatic transport line of the crushing circuit. According to the operator, an electrostatic discharge between the stainless steel ball of the manual level measurement device (in the high position at the time of the incident) and the cell roof caused ignition of a suspended starch cloud; the ball hanging from a non-conducting nylon rope was insulated and become charged during container filling. Following the accident, the cell was cleaned, the filtration box replaced, vents repaired and manual level measurement devices of the 6 containers replaced by analogue probes.