Presentation on theme: "High Potential Near Miss Dropped Object Dropped Wrench While Man-riding 17 th Sept 2010 Incident Investigation Findings Rowan JP Bussell Presented by :Steve."— Presentation transcript:
High Potential Near Miss Dropped Object Dropped Wrench While Man-riding 17 th Sept 2010 Incident Investigation Findings Rowan JP Bussell Presented by :Steve McWilliam, Shell Egypt N.V.
229 th Sept 2010 OVERVIEW OF INCIDENT 17 th September 2010 at 17:15 hrs. After completion of a liner cement job, a floorman was instructed to ride the man-riding winch to close the lo-torq valve and remove the cementing line. Employee ascended with hammer and TIW wrench and prior to closing the valve, the wrench weighing 1.8 kg fell 14 metres to the drill floor. No injuries occurred.
429 th Sept 2010 WHAT HAPPENED Liner was pulled back 2.5 metres after tagging bottom and cement job performed. The operation of closing valve was done after pulling back the liner running tool to the circulating position – hence working height of 14 metres. Work Permit, Job Safety Analysis and man-riding checklist were in place for the job (more details in later section)
529 th Sept 2010 WHY DID IT HAPPEN (Immediate Causes) Snap hook connector not used correctly – tether should pass through the eye of the connector to prevent accidental drop-out. Tools aloft hammer was correctly tethered but not the wrench. Snap hook connector did not have locking device. The above two conditions would allow the tether to drop out if the connector rotates – confirmed by reenactment. Although disputed by floorman, the tool could have been removed from the connector to perform the task. Correct Incorrect
629 th Sept 2010 CONTRIBUTING FACTORS (Failed / Missing Barriers) (1) The running string was not spaced out or positioned to minimise the height at which this activity was performed. The rig procedure for Working At Heights, identifies the risk of dropped objects and specifies the use of tool tethers and tools aloft register. However, the requirement of only one tool per tether and the requirement to only use approved tethers through the eye of the connector is not explicitly stated in the procedure. A pre-man-riding checklist was completed by the AD on the man-riding floorman prior to the job. However, this check was not effective in identifying the use of non-compliant tether. The checklist was only available in English so Egyptian buddy-buddy checks not possible The requirement to use checklist and the responsible person is not identified in the Working at Height procedure
729 th Sept 2010 CONTRIBUTING FACTORS (Failed / Missing Barriers) (2) Although snap hook connectors have been ordered as part of tool aloft kit from a reputable North Sea provider, the supplied connectors without locks are not aligned with the DROPS Forum handbook Reliable Securing. Zip tie is not an approved tether and its short length (~30cm) may result in requirement to remove tool from connector to more easily perform the task. Zip tie was connected for purpose of hanging it on a hook outside the drillers cabin. There is no dedicated tools aloft tool for this job. Although the TIW (kelly cock) wrench is not the correct tool for the job, it was the best available at the time. The dedicated lo-torq wrench is a straight rod that is more difficult to use especially when working at heights.
829 th Sept 2010 ROOT CAUSES (1) DROPS Forum requirements for locking connectors has not fully penetrated the tool suppliers. Examples of tool tethers from UK suppliers Compliant with DROPS Reliable Securing Handbook Non-compliant with DROPS Reliable Securing
929 th Sept 2010 ROOT CAUSES (2) Ergonomic tools aloft tool for closing lo-torq valves at height does not appear to exist. Due to the frequency of man-riding activities on the JPB, there is a possible perception that it is routine activity, even though it is covered by PTW. As a result, thoroughness / quality of pre-manriding checks inadequate Insufficient challenge by the team to minimise the number and height of man-riding operations.
1029 th Sept 2010 OTHER OBSERVATIONS All personnel involved (AD and 3 floormen) had attended the Tools at Height training and competency assessment forms completed. Red Zone procedures were in place for controlled drill floor access and the area had been cordoned off for this job. Requirement for man-riding during cementing operations : Cementing operations requires 5 man-riding activities to connect / disconnect lines and open / close valves. Floating drilling operations predominantly use pneumatic plug dropping heads due to the ban on man-riding activity while block is moving (drill string is compensated while cementing)
1129 th Sept 2010 ACTIONS Corrective Action 1.Take snap hooks (without locking) out of service and temporarily replace with 4-part shackles with split retention pin. 2.Procure snap hooks with locking mechanism for use with tools aloft kit. 3.Review the availability and suitability of pneumatic plug-dropping head for future casing and liner cementations 4.Conduct systematic review of all man-riding operations with aim to eliminate or reduce height of activity. This to include list of tools required for the job 5.Design / Procure a dedicated tool for closing lo-torq valve at heights 6.Translate the man-riding check-list into Arabic 7.Revise the Rowan man-riding procedure to specify more details on type and use of tethers and snap hooks or shackles with secondary retention. Specify responsibilities and use of man-riding checklist i.e. buddy checks and final check by supervisor before man-riding. 8.Feedback incident learnings to supplier of tool aloft kit and DROPs Forum. 9.Review compliance against the DROPs Reliable Securing and close out gaps.
Background : This bulletin is an extension of the previous Early Learning Bulletin, subsequent to the full investigation and significant incident review. It also includes the recommendations considered most appropriate for lateral learning value. What happened: After cementing the liner, a floorman was instructed to man-ride to close the lo-torque valve and remove the cementing line from the cement head. The floorman ascended with hammer and wrench but before the valve could be closed, the wrench weighing 1.8kg fell 14 metres to the drill floor. No injuries occurred. SENV WELLS Learning From Incidents Fountain: 564176Location: Egypt – NW Demiatta Date: 17th Sept 2010 Investigation Findings: Zip tie is not an approved lanyard. Its short length (~30cm) may have required the tool to be removed from the connector to perform the task. The snap hook connectors were supplied as part of a kit from a reputable North Sea provider, but were not compliant with the Shell DROPS ABC Best Practice or the DROPS Forum Reliable Securing handbook which requires connectors to have a locking device. Snap hook connector was not used correctly; cable tether should pass through the eye of the connector to prevent accidental opening of the gate. There is no dedicated tools aloft tool for this job. Tools At Height video shows use of non locking connector. Red Zone Procedures (controlled drill floor access) as well as physical barriers for this particular job were in place and provided mitigation against serious injury. DROPS gap analysis is only conducted against the mandatory requirements and a good level of compliance had been achieved. However, there are a lot of further best practices in the DROPs ABC that may not be captured in the gap analysis. NM: Dropped Wrench While Man-riding Lateral Learning Recommendations: Check the type of snap hook connectors in the tools aloft kit to ensure they have a locking device Review the tools aloft kit to ensure that it contains tools to perform all foreseeable working at heights tasks. When rolling out the Tools At Height training, indicate the use of non- compliant connector when Peter clips the tool on the tether. Once a good level of compliance has been achieved against the DROPS mandatory requirements based on gap analysis, it is recommended to systematically review compliance against the DROPS ABC Guide. Non-compliant (non-locking) connector and tether Compliant connector with locking