Abstract: Employee #1, a welding technician, descended a ladder into a cylindrical component which contained argon gas to check the quality of a pending welding operation near the top of the component. The component was approximately 7 ft diameter and 16.5 ft in depth. This could have been done with a mirror without entering the tank. The bottom openings were covered with removable pads and the only opening was at the top. Employee #1 did not inform management of his intent to enter and an unreported entry had also been made during the previous shift for the same purpose. An additional argon purge had been added during the previous shift and some of the bottom pads removed for ventilation and replaced at the end of the shift. Employee #1 had been informed of the above actions. The time lapse between replacement of the pads and entry of Employee #1 was three hours and twenty minutes. Entry had not been scheduled nor anticipated and the companies confined space procedures were not in place. No tests had been conducted prior to entry. The employee died of asphyxia.