Two employees were participating in a training in the main control room and were tasked with turning on an electric motor that was located in the adjacent steam flake room. The pull switch was engaged and a soft start initialized but failed. An employee pushed the reset button and performed the start sequence again. When the machine spooled up to full speed, a flame shot out of the electric cabinet and an explosion blew the concrete roof off the building. Employee 1 went for the north door and became trapped under an electrical cabinet that fell over. Employee 2 exited through the south door. One employee sustained a fracture. Both employees sustained burns and were hospitalized.