Driller's Inattention Results in Dropped Blocks

Cause & Consequence

• Moving, flying or falling object

Incident Location

Any Location Type

Incident Activity

Drilling, workover

Lessons Identified

• An excess amount of slack in the drill line allowed the blocks and top drive to free fall once the bit broke through the bridge.

• Due to simultaneous operations the driller was not paying full attention to the weight indicator and was distracted by other operations going on at the same time.

Incident Recommendations

To address this incident, this company did the following:

• The rig manager and driller were instructed that if the driller is distracted in any way during simultaneous operations he shall stop the job to regain focus on the task and keep constant attention on the weight indicator.

• The crew was reminded that a JSA for washing and reaming shall be reviewed and/or updated to point out possible hazard scenarios and the information shall be shared among all crews throughout the fleet.

• The company installed a new block dolly system that will stay in the mast at all times. This will prevent the blocks from hanging out over the top drive creating slack in the drilling line during similar operations or events.