The following is a real-life example of what went wrong and what corrective measures resulted from incidents in the oil and gas industry. It’s taken from hazard alerts issued by WorkSafe Saskatchewan.

What happened:
A Saskatchewan drilling rig worker died when a twin clevis link used in a tugger hoisting assembly failed, dropping a 1,200-pound (544-kilogram) drill pipe onto him.

At the time of the accident, the drilling crew was laying drill pipe down the v-ramp on the rig. This involves using a tugger line to pick up pipe from the mouse hole. Workers stand behind the pipe and push it over the edge of the rig floor onto the v-ramp. The pipe is then lowered with the tugger line, via the rig’s v-ramp, to the catwalk below.

The rig worker was under the pipe being pushed when the twin clevis link broke.

What caused it:
An investigation showed that the twin clevis link did not meet acceptable standards. In this incident, the clevis link was not designed for overhead lifting, not manufactured from Grade 80 alloy-based steel, and should not have been used for that application. Only Grade 80 or better alloy-based steel rigging and components should be used in overhead lifting applications.
Only a cotter key kept the tugger line and tail chain attached to the twin clevis link. Investigators noted that more secure fastening was required. In addition, the tail chain was too small to work properly with the clevis link.

Effective prevention:
The occupational safety and health regulations require employers in the industry to ensure the right tools, equipment and components are provided and used correctly.

Therefore, employers must:

• Ensure that the rigging is safe.
• Ensure that workers are trained to use it correctly.
• Ensure that rigging is regularly inspected at intervals recommended by the manufacturer.
• Provide the necessary information, instruction, training and supervision to protect workers.
• Ensure the workplace is competently supervised and that supervisors comply with regulations.
• Train workers to recognize hazards and work safely. Before starting work, an employer must ensure that no worker is permitted to perform work unless trained.