Abstract: On May 24, 2011, Employee #1, rig operator and team leader, and an oilfield service rig crew were removing and replacing a down well pump. They set the rig up on the well and started prepping the well for the pump removal. The pumping unit was placed in the down stroke position with the horse head down and the counterweights up in the vertical position. Employee #1 then engaged the pumping unit brake, but had some difficulty. A coworker helped him and they both pulled on the brake control handle; however, it did not appear to be holding, and a restraining chain was ran through the spokes of the gear box pulley down to the unit frame. The well bridle was unhung and the horse head removed from the end of the walking beam. They next removed the polish rod and laid it down. They were starting to remove the sucker rods to which the pump was attached, but found that the rig traveling block would contact the end of the pumping unit walking beam. Employee #1 and the coworker went to the back of the unit to put in the up stroke position. Employee #1 stepped on the unit frame to unhook the binding chain and the coworker went to the unit brake handle to control the counter weight descent. Employee #1 was seen struggling with the boomer that put the chain under tension, when the coworker heard a noise and saw the counterweights starting to move slowly. The coworker warned Employee #1 that the chain had become loose from the frame and wrapped around the pulley shaft with it free end flailing. Employee #1's attention was on the chain and he stepped back. The south counterweight contacted his upper torso. The counterweight continued to push him down into the unit frame where the counterweights swing through. Employee #1 was caught between the counterweight and the gear box pedestal. His fellow employees were unable to remove him and summoned for emergency medical personnel. Employee #1 sustained crushing forces from the objects that asphyxiated him.