An explosion took place on the furnace of a refinery’s atmospheric distillation unit. A violent thunderstorm was responsible for generating various incidents in this unit, as a result of power outages. The furnace was thus turned off and then back on about 4 hours later. Approximately 45 min after start-up, the boilers were activated due to the lack of fuel and experienced a pressure loss on the steam network. An air pressure drop followed at the level of the system instrumentation, with the collapse of the gas fuel network, along with a pressure drop at the level of the pilots, including those of the specific furnace which were extinguished. The explosion actually happened inside the furnace by means of self-ignition of the accumulated gases. The origin of this accident stems from the poor meteorological conditions: an unfortunate lightning/thunderstorm combination.