Abstract: Employee #1 was assisting the company owner in precision testing the air conditioning fan drive shaft bearings inside a roof-mounted air conditioning unit. Employee #1 was operating the probe as the owner was reading the meter. When they finished testing one set of bearings, they moved approximately 4 1/2 ft to the left to test the bearings on the other fan. Employee #1's loose outer shirt became entangled in the rotating drive shaft. He was pulled under the drive shaft and the electric lighting extension cord he had been holding became entangled around the drive shaft. The cord struck him continuously as he lay under the shaft, until the fan could be de-energized. Employee #1 was injured by the whipping extension cord.