Abstract: At approximately 9:40 a.m. on February 26, 2014, Employee #1, a mechanic, was working for a drilling company. The company specialized in environmental drilling to determine the presence and absence of subsurface contamination. Employee #1 and two coworkers, were assigned to a three-man crew and tasked with re-spooling 0.625 in. wire rope back onto the drum on Rig Number S1095 (Air Rotary Rig TH50). While re-spooling the wire rope, Employee #1 maintained tension on the wire rope, as one coworker operated the controls to the winch line lever and the other coworker, the lead mechanic, ensured the wire rope was spooled correctly onto the drum. As the wire rope continued to spool, Employee #1 released tension on the wire because the block itself provided tension while the wire traveled vertically. The bolts on the outer face of the block caught the lip of the lower drill table. Employee #1 grabbed the block (Single-sheave Block Number 280) with his hands in order to pull it free. Employee #1's right hand was caught in the pinch point created by the sheave and the wire rope. Once freed, the block continued to travel vertically resulting in a serious injury to his right hand. Employee #1 was transported to a medical center, where he was treated and hospitalized for the serious hand injury, which possibly involved a hand amputation.