Backup Cause & Consequence
Moving, flying or falling object, Slip, trip or fall on same level
Backup Contributing Factor
Complacency, Control of work, Culture
Description of Process
Hand jarring during slickline operations
Description of Incident
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
Good Practice Guidance
Site / task specific risk assessment to be carried out by the team prior to commencing hand jarring
Only hands to be placed to on wire during jarring operations
No other body part (including legs) to be place on, over or under the wire
Jarring only to take place between unit and bottom sheave and not in the vertical position
Operator to be in a position to pull wire back so that a sudden tension will result in the wire moving away from the operator
Operator to be positioned a safe distance from the sheave to prevent entrapment with sheave
Suitable level work site for operators free of potential tripped hazards to be provided
Contact Details
Colin Esslemont, Wells HSE Lead, Centrica Exploration & ProductionRate this alert
Average Rating
Latest Alerts & Moments
Our searchable catalogue of hundreds of Safety Alerts and Safety Moments are all designed as learning resources that can help improve workplace safety.