Abstract: Employee #1 and a coworker were cleaning a cement mixing machine that supplied cement to a concrete block making machine on a lower level. After opening the disconnect switch and locking it out, they entered the mixing machine bin and used air-powered chisels to clean the interior surface. Employee #1 received a phone call and went downstairs to the office to answer t while the coworker continued cleaning. When the coworker finished, he went behind the mixer as part of the cleaning procedure to hammer on a hopper that was not visible from the front of the machine. After cleaning the hopper, he walked around the machine to the wall opposite and to the right of the mixer, but within view of it. He looked at the mixer but did not see anyone, and unlocked the disconnect box. The coworker then closed the circuit to the mixer, and pushed the START button. When he looked at the mixer again, he saw Employee #1 caught between the mixer blade and the inside of the bin, facing toward the back of the bin. Employee #1 was extricated from the machine and rescue services were called. He was killed.