Slickline Hand Jarring results Lost Time Injury

Whilst carrying out well services operations on an NUI (Normally Unmanned Installation), a member of the well services crew sustained an injury to their lower right leg.

At the time of incident the injured person (IP) was in the process of hand jarring the wireline and in doing so he placed his right foot on top of the horizontal section of the wire to apply downward pressure. At the same time, he pulled the vertical section of the wire with his hand in order to jar the wire. As he carried out the 1st jar, the tool string, which weighed 130kg, dislodged from a hung up point in the wellbore and dropped a further 2-3ft. This caused the wire at surface to come under tension and spring upwards 3ft causing the IP's right foot to move upwards, which in turn caused him to twist and fall over.

The IP's resulting injury was a double fracture to the lower leg.

What Caused it:

• Risk awareness / hazard perception by wireline crew as to potential stored energy in wireline

• Requirement to hand jar was not considered when placing equipment on site

• Wire line impact on the injured person lower leg caused the stored kinetic energy from the wire to travel through his leg, resulting in a double fracture to his tibia/leg bone

• Operator placed foot on top of wire to assist in jarring operations

Corrective Actions Taken:

• Vendor's procedures amended to include a statement on correct body position for hand jarring operations

• Specific hand jarring risk assessment added to permit pack and permit to work system

• Improved training on the risks associated with hand jarring