(Richmond, IN)--Firefighters spent hours at Richmond’s Purina plant Tuesday. A drier had caught fire and was put out by employees. "However, the fire had extended into the ventilation system." said Battalion Chief Tim Brown. The building was never in jeopardy. Here’s what made the fire tricky. "It was difficult to get to the fire because of the vent system. There were only a few access panels to where we were able to get to the fire," Brown explained. Firefighters were on the scene for more than five hours. The incident caused production to be stopped. Employees had been evacuated before firefighters arrived.