Brent Bravo Utility Leg Fatality – Jan 2005 Report Findings from the Shell Investigation Team
Brent Bravo Utility Leg Fatality – Jan 2005 Agenda • Brent Bravo • Summary of what happened on the 1 st January 2005 • Results of the Investigation • Findings and Actions
Brent Bravo Utility Leg Fatality – Jan 2005 • Situated 116 miles north-east of Shetland • Concrete Platform • Exports gas from the rest of the Brent Field into the FLAGS pipeline system • Three legs – one accessible (utility shaft), 2 flooded.
Brent Bravo Utility Leg Fatality – Jan 2005 Key Observations • The circumstances of this incident and the incident of September 11 th, 2003 are completely different • At no time during the incident was there a hydrocarbon gas atmosphere in the leg • Both men followed the correct alarm response procedures in evacuating the leg • The platform personnel did an excellent job responding to the incident
Brent Bravo Utility Leg Fatality – Jan 2005 What happened • Normal platform operations prior to incident • Two Electrical Technicians, on night shift, were in the leg at the 76 metre level installing services for a planned inspection of pipework below the 76 metre level. • At around 02: 20 hours both men smelled H 2 S and at the same time 1 of 4 portable gas monitors at the worksite alarmed at 5 ppm H 2 S None of the fixed toxic gas monitors nor any of the hydrocarbon gas monitors went into alarm. • • Both men donned their Draeger Rebreather sets and, in accordance with procedures, started to evacuate the leg by climbing the internal stairs. • At the 81 metre level one of the men stopped and activated the platform GPA and then continued to climb the stairs.
Brent Bravo Utility Leg Fatality – Jan 2005 What happened (con’t) • • ---- EL 124 m • • • At a stair landing just below the 124 metre level one of the men (Graeme Burns) stopped climbing and sat down on the stair landing The other man continued to climb the stairs out of the leg believing Graeme was taking a rest and would soon follow. The second man reached the top of the leg at 02: 33 hours and informed the leg sentry that Graeme was following behind him. Several tannoy messages were given by the OIM to tell Graeme that the leg was gas free. A two man rescue party was sent into the leg and found Graeme laying on the stair landing where he originally stopped – just below 124 metre level. Graeme was given CPR by the rescue team and the medic was called to the scene. The rescue party were unable to resuscitate Graeme.
Brent Bravo Utility Leg Fatality – Jan 2005 Cause of Death • The Death Certificate indicates Graeme died as a result of a heart attack caused by a coronary artery thrombosis. • We have no further information about the cause of death, but what we do know is: – Graeme had a valid UKOAA offshore medical certificate – The gas monitor that alarmed reached a maximum H 2 S value of 6. 7 ppm (the other portable showed zero, and neither personal meter alarmed during the event). The 6. 7 ppm is well below the Theshold Limit Value - Short-Term Exposure Limit of 10 ppm – All of the gas detectors were independently tested and found to be operating correctly – The rebreather set was also independently tested and found to be operating correctly
Brent Bravo Utility Leg Fatality – Jan 2005 Investigation Findings H 2 S in the Leg Background • By design the bottom of the leg contains seawater to a depth of approximately 35 metres. • A consequence of this seawater is that H 2 S gas is produced by naturally occurring Sulphate Reducing Bacteria (SRB) • The H 2 S is managed by continuous sparging with air and diluting with fresh seawater and when required chemical treatment. • The Threshold Limit Value – Short Term Exposure Limit for H 2 S exposure is 10 ppm (meaning the value to which nearly all workers can be exposed to for up to four, 15 minute intervals per day without adverse health effects). Findings • The seawater had been treated with a chemical scavenger a week before the incident • At the 76 metre level, the reading was 0 ppm in the days prior to the event • The gas monitor that alarmed reached a maximum H 2 S value of 6. 7 ppm. • Laboratory examination of the portable gas monitors indicated they were working correctly at the time of the incident and giving accurate readings.
Brent Bravo Utility Leg Fatality – Jan 2005 Investigation Findings Gas Meters Background • The men had in their possession 4 forms of gas detection (2 Crowcon Tetra Portables and 2 personal gas detectors). • There were 11 fixed detectors at, above, and below the 76 metre level where the men were working. • Only one of the detectors gave an indication of H 2 S (one of the Crowcons) Findings • The Crowcon that alarmed reached a maximum H 2 S value of 6. 7 ppm. • It had not been reset at any time during the incident or after • Laboratory examination of the portable gas monitors indicated they were functioning normally and giving accurate readings
Brent Bravo Utility Leg Fatality – Jan 2005 Investigation Findings Draeger Rebreathers Background • Introduced in 2003 on all Shell UK platforms to replace existing rebreathers following trials at RGIT Montrose. • The sets are widely used in the military, nuclear, mining, and oil and gas industries Findings • Both men had been trained in the use of the Draeger sets and had been assessed as leg competent • Based on the video evidence, both men had not donned the units in strict accordance with the manufacturers recommendations • Laboratory examination of the unit worn by Graeme confirmed it was functioning normally • Andy reported the unit worn by him was also functioning
Brent Bravo Utility Leg Fatality – Jan 2005 Investigation Findings Medical Fitness of Personnel Working Offshore Background • The medical fitness requirement for personnel working offshore in the UK is the UKOOA Offshore Medical. • The UKOOA medical examination does not require a test of aerobic fitness such as the Chester Step Test. Although this is still part of the Shell Medical examination for offshore staff. Findings • Graeme had a valid UKOOA Offshore Medical Certificate
Brent Bravo Utility Leg Fatality – Jan 2005 Investigation Findings Other Issues Leg Entry Control • The procedure for the monitoring of personnel movements into and out of the leg was not being strictly followed in accordance with the OCOP Leg Competency Training • The Leg Competency training in the use of portable gas monitors only requires personnel to understand the meaning of the alarms – not how to reset and retest for harmful atmospheres Radio Communications • There was cross-channel interference during radio communications First Aid Response Time • The time taken to get First Aid support to casualties in the lower half of the leg, when using the stairs as access, is longer than the Shell standard of 4 minutes
Brent Bravo Utility Leg Fatality – Jan 2005 Immediate Follow-Up Actions (Underway) 1. • Emergency Escape Rebreather Training Immediately re-train all platform personnel in the use of the Draeger rebreathers (where applicable) – Show the instruction DVD – Have an appropriate person (medic, etc. ) physically demonstrate the use of the equipment – Encourage people to use the “buddy system” to check each others deployment in the event they are ever needed – Re-emphasise the advantages of the Draeger system – Carry out practical exercise by donning training sets (when available) 2. • Leg Entry Control For the concrete leg platforms, immediately test the application of the appropriate leg entry Operating Code of Practice (OCOP) to ensure the effectiveness of leg registers Carry out regular “spot checks” to identify all personnel in the leg at a point in time and then validate against the Leg Register detail. •
Brent Bravo Utility Leg Fatality – Jan 2005 Follow-Up Actions (Planned) 3. • Medical Fitness Review medical fitness requirements for personnel in the legs of concrete gravity base structures in consideration of the unique requirements for ingress and egress 4. Enhanced Training • As already agreed with the HSE previously, enhance rebreather training. • Review the requirements for Leg Competency and if necessary include requirement for training in the use of portable gas monitors 5. • Radio Communications Carry out planned work to upgrade radios to avoid cross channel interference immediately. 6. • First Aid Response Time Review First Aid response time for casualties in concrete legs and ensure the risks are ALARP Concrete Leg Working Environment Form a joint Shell/Sigma 3 team to evaluate additional improvement opportunities specific to the unique environment of concrete legs 7. •
Brent Bravo Utility Leg Fatality – Jan 2005 Summary • • • The circumstances of this incident and the on September 11 th are very different At no time during the incident was there a hydrocarbon gas atmosphere in the leg Both men followed the correct alarm response procedures in evacuating the leg The platform personnel did an excellent job responding to the incident The Death Certificate indicates Graeme died as a result of a heart attack caused by a coronary artery thrombosis. Graeme had a valid UKOAA offshore medical certificate The gas monitor that alarmed reached a maximum H 2 S value of 6. 7 ppm (the other portable showed zero, and neither personal meter alarmed during the event). The 6. 7 ppm is well below the Theshold Limit Value - Short-Term Exposure Limit of 10 ppm All of the gas detectors were independently tested and found to be operating correctly The rebreather set was also independently tested and found to be operating correctly There were other improvement opportunities discovered that are being actioned
Brent Bravo Utility Leg Fatality – Jan 2005 Requests of You Complete The Ones I already made to you on January 7 th • Immediately re-train all platform personnel in the use of the Draeger rebreathers (where applicable), as per my instruction on January 5 th – For installations using other types of rebreathers, do the same with your existing training package • For the concrete leg platforms, continue to test your application of the appropriate leg entry Operating Code of Practice (OCOP) to ensure the effectiveness of leg registers New Requests • Use elements of this slide pack to communicate to all platform personnel ASAP • Re-educate all platform personnel in the dangers of hydrocarbon vapour (next slide) • Confirm to your Ops Manager and Asset Leader via email when you have completed these requests • Ensure these same requests are handed over to your back-to-back
Brent Bravo Utility Leg Fatality – Jan 2005 Additional Observations Not Connected with the Incident There is evidence that these risks are still not understood by the workforce. Please re-communicate the dangers of breathing hydrocarbon vapour to all members of the workforce. Failure to respond to verbal commands 80% Hyper-excitation, loss of ability to take rational decisions Likely there is no impairment of functionality No impairment of functionality 60% 40% 20% 10% % Lower Explosive Limit A key finding from the September 2003 incident was a lack of awareness of the risks associated with the ‘Narcotic Effect of Hydrocarbon Gas’ 100%
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