Metallurgical failure analysis was requested after a pressure regulator and valve on a helium tank was involved in an oilfield accident. J.E.I. Metallurgical, Inc. was asked to determine if a design defect or any damage to the regulator played a part in the subject accident. The necessity of warning labels for the regulator was also considered. Visual and x-ray examinations were performed on the regulator. No obvious design or manufacturing defects were revealed. The subject accident was determined to have occurred as a result of improper usage of the helium valve.