Tubing string ejected from well

Cause & Consequence

• Moving, flying or falling object

Incident Location

Drilling unit

Incident Activity

Well services / intervention

Incident Info Source

Step change in safety

Specific Incident Equipment

Hydraulic Workover Snubbing Unit

Lessons Identified

The HWO controls were NOT fail safe. Equipment design did not preventthe operator having both sets of slips partially open when the pipe weight is <4500lbsThe investigation identified system failures in the management of the HWO unit, specifically with regard maintenance, operating procedures, competence and supervision.Defined competency for safety critical positions were not adhered to in the selection of personnel, the client failed to verify competence of these individuals.

Incident Recommendations

Design of snubbing unit controls to incorporate fail safe interlock system.

Competency verification of contractor staff