The operation at the time was running casing, which necessitated the use of hydraulic power tongs. The tongs were suspended by an air hoist and left energized between connections. During a break while running the casing, the decision was made to relocate a bag of protectors to the ‘V’ door. The hydraulic tongs were lowered to the floor left energized with the door open the tugger was removed. The tugger was then used to move the bag of protectors. Once the bag of protectors had been relocated it became necessary to hook the tugger back up to the hydraulic power tongs. A floorhand assisted the Tong Operator to reconnect the air hoist onto the power tongs and in so doing the floorman placed his right foot between the door openings. During the process of hooking up the air hoist, the spring on the lifting assembly engaged causing the gear mechanism to rotate which resulted in the floorman’s foot being caught. The resulting injury led to the partial amputation of the right foot forward of the ankle.