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LTI: worker lost his thumb

What happened?

During drilling operations, a worker got his thumb caught under a part of a drill being lowered into position, resulting in the amputation of the thumb just above the knuckle. The incident occurred during operations to retrieve core samples from the borehole. Our member notes that an Inner Barrel is deployed by freefall to latch into the Bottom Hole Assembly (BHA) of the drill string. The Inner Barrel was lifted into position by winch, attached to the Overshot, and lowered into the casing, ready to be deployed. On this occasion, whilst deploying (de-latching) the Inner Barrel from the Overshot the assistant driller positioned his hands as shown in the photograph to depress the latch release keys. As the Inner Barrel dropped under its own weight his left thumb was caught between the latching ring and the top of the casing resulting in the amputation of the thumb just above the knuckle.

The IP was taken to the nearest hospital. The medical team were unable to save the tip of his thumb.

What went wrong?

  • Bypassing safety controls: the injured person failed to understand or use safety-critical equipment or follow procedures applicable to this task;
  • ‘Line of Fire’: the injured person got in the way of falling/moving objects.

What actions were taken?

  • Full review of all aspects of this task including revision of task work instruction and method statement;
  • Drill crews have been reminded to use the appropriate Lay Key intended for this task.

Members may wish to refer to:

Safety Event

Published: 28 April 2020
Download: IMCA SF 14/20

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