At around noon, slow-burning embers formed in a pellet cooler at a livestock feed mill. A technician opened the door to the pellet press to clear its die and dump jammed feed onto the ground after the pellet die overheated following a jam when a batch was started. The insulating plate under the door was not correctly positioned, allowing embers to accidentally fall into the cooler located below. The line was then restarted. The stream of air stoked the embers, which spread to the 1.2 t of pellets in the cooler. Upon reaching its temperature set point (65 °C), the safety thermostat on the cooling air discharge pipe tripped, turning off the fan, closing the air damper, stopping the circuit, and causing an alarm to appear in the control room. The maintenance workers turned on the spray bar inside the cooler. The first-response team safely shut down the mill and evacuated the workers. The fire was under control when the firefighters arrived. The firewater was contained in the pellet tower’s pit. It and the wet pellets were pumped up by a specialist firm to be disposed of via the approved routes. The plant resumed production at 2:00 p.m. The pellet line was restarted 24 hours after the fire.

The operator took the following measures:

• An automated system that enables feed to fall directly into the sack of waste when the door of the press is opened has been installed.

Existing procedures are kept up to date (annual calibration of temperature sensors; operating check of automatic safety systems and sprinkler systems inside the coolers; regular simulation exercises involving employees).