Around 5 pm, the personnel at a cattle feed plant noticed a fire outbreak at the end of a silo conveyor belt and alerted emergency services. The fire spread along the belt, which straddled the Rennes-Brest railway line, then reached a material handling tower and jumped to a 2nd conveyor belt. Rail traffic was interrupted for 2 hours. Fire-fighters controlled the blaze using 4 nozzles, battling the fire to within a few metres of a flat silo. No injuries were reported. A monitoring system was implemented in order to overcome any eventual resumption of the fire. The Inspection authorities for classified facilities performed an investigation. According to witnesses, the fire had spread over 100 m of conveyor belt length in some 20 minutes. The metal fairing protecting this belt from foul weather had created a “chimney effect” as the fire burned. Installed in 1999, this “type K” belt (with fire-retardant lining) was compliant with standard NF EN 20340 according to the manufacturer. The tests conducted in June 2005 by a third party on a portion of the belt spared from the flames showed that it still met the requirements of the standard for specimens inclined at a 45° angle, but was not compliant with requirements for a vertical specimen position with respect to the flame persistence criterion; these conclusions were challenged by the belt manufacturer. Regarding a “type K” model, the issue of durability of the self-extinguishable characteristic was raised (i.e. accounting for lining wear?). Heating of a thrust bearing at the level of the counterweight tensioning device had caused this fire. Subsequent to the accident, the operator planned to replace the metal part of the footbridge straddling the railway, in addition to installing “smoke domes” on the fairing in order to limit the “chimney effect”.