the rig, where the flow might have been directed overboard or where the rig itself might have been disconnected from the well and repositioned. Had the rig been able to disconnect, the primary fuel load for the fire would have been eliminated.

OBSERVATIONS

Evacuation

Observation 4.1: The actions of some crew members in requiring due consideration of additional survivors before launching lifeboats, despite the fearsome fires engulfing the rig, are commendable and were important in the highly successful evacuation.

Observation 4.2: The attempts to start the standby diesel generator and restore power for damage control were acts of bravery.

Observation 4.3: Conditions of explosion, fire, loss of lighting, toxic gas, and eventual flooding and sinking could have resulted in many more injuries or deaths if not for the execution of the rig’s evacuation.

Rules for Rig Propulsion Control Systems

Observation 4.4: American Bureau of Shipping (ABS)20 rules require that propulsion control systems for MODUs shall “in general” comply with the Steel Vessel Rules. This requirement may give rise to ambiguity concerning primary control and monitoring systems on MODUs.

RECOMMENDATIONS

Summary Recommendation 4.1: Instrumentation and expert system decision aids should be used to provide timely warning of loss of well control to drillers on the rig (and ideally to onshore drilling monitors as well). If the warning is inhibited or not addressed in an appropriate time interval, autonomous operation of the blind shear rams, EDS, general alarm, and other safety systems on the rig should occur.21

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20 As a classification society, the role of ABS is to verify that marine vessels and offshore structures comply with rules that the society has established for design, construction, and periodic survey (ABS 2011).

21 Although it was presented in Chapter 3, the recommendation is also presented here to underscore that the rig, riser, BOP, and drilling equipment are an integrated system.



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