On a Saturday in a plant manufacturing bitumen and road surfacing materials, an explosion occurred followed by fire over the upper part of a tank containing fluxed bitumen. The cup forming the tank’s upper section and a vent were both torn off by the deflagration. All lights in the adjacent workshop were destroyed. As fire-fighters equipped with water hoses responded, the turbulence caused bitumen to overflow from the tank. Continuous sprinkling after fire extinction sufficiently cooled the tank to the point of avoiding a secondary accident; only the heat insulation on a nearby tank was damaged. The site was placed in safe operating mode by turning off all electricity and gas supply. The extinction water confined in the retention basin was pumped and disposed. The tank involved in the accident had been filled to 1/3 its capacity, with the 60 m³ total bitumen content held at constant temperature by a heated oil coil. According to the plant operator, the safety system, which called for shutting down the heating device when bitumen reached 150°C, had been operating normally; however, given the exceptional outdoor temperature (38°C), a pressure surge was still unavoidable. The tank had not been fitted with a pressure sensor, and the vent (found on the ground some 10 metres away) appeared to be in good condition. The operator conducted an in-depth investigation to determine the origin of the accident and proposed to Inspection Authorities for Classified Facilities a study and implementation of measures intended to reduce the probability of recurrence for this type of accident.