Human And Organizational Error In Operations Of Marine Systems:Occidental Piper Alpha And High-Pressure Gas Systems On Offshore Platforms
Authors: Moore W.H. , Bea R.G. 
Published: October 2008

The paper establishes methodologies for formulating qualitative and quantitative models to identify and evaluate the impacts of human and organizational errors (HOE) on offshore operations. Qualitative and quantitative models of simultaneous production and maintenance related to Piper Alpha disaster are used as a case study to illustrate the identification and assessment of alternatives to minimize the effects of HOE in high pressure gas system operations. Quantitative data is limited in availability and detail to assist evaluations of HOE management alternatives. However, when this data is combined with a realistic structuring of the human, organization, and system com orients of marine systems, then useful results can be developed to guide judgments to improve the reliability of these systems.

INTRODUCTION

Available data on the performance of marine systems during the last two decades indicates that approximately 6570 of catastrophic marine related accidents are the result of compounded human and organizational errors (HOE) during operations.

In spite of this experience, there is no structured, general, qualitative and quantitative approach to assist engineers, operators, and regulators in the evaluation of alternatives to help minimize human and organization errors in marine systems. To be able to realize significant improvements in the reliability of marine systems, guidelines and procedures should be established to include explicit consideration of human and organizational errors as an integral part of the design, construction, and operation of offshore structures.1 This paper examines methodologies used to mitigate the impacts of HOE during operations of offshore structures. A case study of the Piper Alpha disaster is used to illustrate examination of the effects of HOE in simultaneous offshore maintenance and production operations of high pressure gas systems. Influence diagrams are developed to illustrate the interactions of the multiple accident events, decisions, and actions and to evaluate their contributing HOE factors. The models are used to examine HOE management alternatives reduce the likelihood of failure events.

BACKGROUND

Development of accident framework models is the third of five tasks in the Joint Industry Protect titled Management of Human Error in Operation of Marine Systems conducted by the Department of Naval Architecture & Offshore Engineering at the University of California at Berkeley during the past three years. The five tasks are:Identify, obtain and analyze well documented case histories and databases of tanker and offshore platform accidents whose root causes are founded in HOE.Develop a classification framework for systematically identifying and characterizing the various types of HOE.Develop general analytical frameworks based on a study of real-life case histories of major marine accidents to characterize how HOE interact to cause such accidents.Formulate quantitative analyses for the case histories based on probabilistic risk analysis (PRA) procedures using influence diagrams. Perform quantitative analyses to verify that the analyses can reproduce the results and implications from the case histories and general marine casualty statistics.