Failed "D" Shackle
Description of the hazard
While pulling drill rods the “D” Shackle used to connect the hoist rope to the hoist plug failed catastrophically.
Apparent causes
The “D” Shackle was not appropriately rated for the loads being hoisted and lowered.
Recommendations
All elements of the hoisting system of a drill rig must be designed and used with a factor of safety of 6.
All elements of hoisting equipment (lifting tackle) must be manufactured to a recognised technical standard and must be conspicuously and clearly marked with the Safe Working Load of the piece of equipment.
All elements of the hoisting system must be inspected on a daily basis as a part of the pre-start check.