Abstract: At 2:30 p.m. on April 1, 2019, an employee was working on a crew assigned to service a Watson Hopper Model Payzone 550 oil well. The crew was pulling and running rods on the rig and the employee was assigned to work on the 14 inch wide derrick platform. The crew was pulling 7/8 inch guided rods out of the hole and while pulling up on the 63rd stand the rods drug and the blocks started to swing. A coworker (an operator) addressed the swing by stopping all movement and letting the blocks settle before proceeding. As the 66th stand was latched at the floor, the employee knocked on the mast three times to signal the coworker to begin the lift. The coworker began the lift in 5th gear with a steady pull watching as the blocks went were raised until they reached the bottom of the rod board, at which point he looked down to judge the stopping point for the next connection. The rods began to drag once again and the blocks began to swing again. The coworker was looking down at this point and did not notice the swinging blocks above. The employee, still positioned on the platform, was located between the mast and the moving blocks. The blocks are approximately 15 1/2 inches wide and there is a clearance from the platform of about 4 inches. The swinging blocks struck the employee pushing him against the mast and crushing his chest area causing a pulmonary contusion, requiring hospitalization.