IRATA Safety Notice: Rope Failure caused by unauthorised lift
IRATA Safety Notice- keeping our industry safe
1. The incident A team was performing a potential dropped objects inspection on the forward side of a derrick, from the top of the derrick to midway down using double rope access techniques. A level 1 technician was positioned on his ropes under the crown waiting for his colleague to pass him a tool. At this point the level 1, while still waiting for the tool, felt his main working rope being tensioned towards the bow of the ship, causing him to be pulled away from the derrick in the opposite directions of his two anchors. The tension rope caused his descending device to fail catastrophically (the broken descender device was found more than 50m away from the base of the derrick) and the main rope, that his descending device was on, then snapped at the source of the tension below, causing the technician to swing back in towards the derrick on his back up line. The Level 3 immediately contacted the drill floor, via radio, calling for all activities on the drill floor to be stopped. The level 1 secured himself to the derrick structure and a second set of ropes were deployed by the level 3 who abseiled down to the level 1, once satisfied that the level 1could abseil down without any assistance, the level 3 gave another descending device to the level 1, the level 3 then abseiled down to the next safe level and was soon followed by the level 1, on the new set of rigged ropes, to the same level. All work at height was stopped until further notice. During the incident the snapping rope “whipped” up hitting the top of the level 1’s left leg and knee causing abrasions and severe bruising. Upon investigation of the incident it was found that a member of the drill crew had requested a basket to be lifted by the deck crew but no one had gained authorisation to do this lift. The port forward crane was used to carry out this lift. As the crane moved to carry out the unauthorised lift, the level 1’s rope ends became entangled in the crane boom causing the tension in the lines which led to the incident.
2. Incident analysis 2.1 The deck crew ignored the rope access teams’ barriers and signs and operated the crane without any authorisation from their supervisor. The deck foremen was aware of the rope access activities but he wasn’t consulted about the crane lift over to the drill floor. A sentry in the exclusion zone could have helped prevent this incident. (See ICOP Ref 2.11.8) 2.2 The driller should have been contacted before anyone entered the drill floor; this rule was disregarded by the deck crew carrying out the unauthorised lift. 2.3 Wind direction assisted with the snagging of the ropes. 2.4 There wouldn’t have been any conflict with the crane, even if it did cross the barriers as the rope access work was only supposed to be carried out from the top of the derrick down to the monkey board level (inside the wind wall onto a walkway). The level 3 and team did not recognise the potential hazard of rigging the ropes over the wind wall to deck level. 2.5 The rope access company’s procedures requires rope ends to be kept in bags if there is a risk of them coming into contact with cranes, tugger winches, etc. There was no control of rope ends, by the rope access team, in accordance with company procedures.
3. Control measures implemented
Create a standing Instruction for simultaneous operations, to guarantee that all lifting ops
must be authorised by the deck foreman, that considers crane use while working in derricks
The addition of regular training in company procedures will be implemented.