Abstract: Employee #1 three coworkers were at a gas well and pipeline worksite when air pressure began to build up in the well, at the same time that there was a clog in the flowline joint. The pressure increased until there was a sudden and violent release of pressurized air from the gas well. Employee #1 and coworkers were struck by the air and flowline and were either knocked or thrown to the ground. Employee #1 was killed; the three coworkers were transported by ambulance to the hospital. The employees were not sufficiently trained on how to react in an emergency in which the well was experiencing very high pressure and the flowlinw was clogged. Had they closed off the blowout preventer, the flange of which was connected to the clogged flowline joint, the well would have been secured while they unclogged the flowline.