At 2:10 p.m., a fire broke out in a pizza cooling “gyro” in a fresh pizza and sandwich production facility. The sprinkler system was triggered, and the staff used fire extinguishers to put out the fire before the fire brigade arrived. The firemen evacuated the personnel.

Of the employees present, 25 were treated for smoke inhalation, 5 of whom were taken to hospital for evaluation. The glycol water from the sprinkler system was recovered for processing in the site’s wastewater treatment plant (WWTP). More sustained monitoring of the WWTP was scheduled for the following days. The conveyor of the cooling gyro for one of the pizza production lines had been damaged in the fire. The pizza dough, which was in the resting phase at the time of the incident, was lost, and the pizza bases had been cooked but not topped. This food waste was destined for methanation or animal feed. The combustion waste from the conveyor belt was sent to a landfill for disposal.

The fire had been caused by an ember on the pizza cooling gyro’s conveyor belt. The ventilation system used to cool the pizzas rapidly had fanned the heat source, causing the fire to start. The chronology of the accident was as follows: the oven’s belt had shifted, causing the oven to stop. The employees took up position at the oven’s exit to recover the pizzas still inside and prevent them from entering the cooling gyro. The oven’s conveyor belt was then allowed to operate empty to ensure no material was still present. Despite these precautions, an ember was able to pass over the cooling gyro’s plastic conveyor.

The operator took the following measures:

• slaving of the cooling gyros’ shutdown with the oven alarm;
• water downpipes added at each oven outlet for the production lines not so equipped (water hose used for the line involved);
• review of the procedures for managing oven shutdowns with a bypass for emptying the oven in the event of a shutdown;
• study the technical feasibility of replacing the plastic conveyor with a plastic conveyor with better thermal resistance or a metal conveyor.