A machine at a steel foundry was found to be jammed in the "up" position and could not be lowered. The plant maintenance mechanic, who was an experienced and careful worker, was called to repair it. Some time later, he was found trapped between two machines and crushed to death. The machines had recently been changed in design, necessitating more repairs than before. The pneumatically-operated machine was jammed in the "up" position because of an air line leak, and the air had to be left on during inspection to find the leak. Because of the air pressure, the jam suddenly gave […]