The Ivanhoe/Rob Roy Safety Case Development

Abstract

Abstract The development and submission of installation safety cases is an activity which has and will in the future utilise a significant level of operators' manpower. The Amerada Hess Ivanhoe/Rob Roy fields safety case was prepared and submitted initially to the HSE as an early voluntary submission for a floating production system and then as the formal safety case submission in June 1993. This paper will detail how the safety case was developed starting from the ‘Forthwith Studies’ defined by the Cullen Report. It will detail the various development stages of the document and the changes that were carried out before a satisfactory format was reached. A particular strength identified in the voluntary safety case was the hazard identification and mitigation section, which also includes the hazard inventory. This section will be presented in detail with examples in some of the main hazard groups, namely (i) loss of containment, (ii) dropped object, (iii) marine impact and helicopter crash, (iv) marine system faults, (v) loss of structural integrity and (vi) environmental hazards. The methods used to firstly identify the hazards associated with the installation, then qualitatively risk rank and finally, perform quantified risk assessment will be presented. Detailed information on the dropped object studies will be specifically highlighted. This paper will provide an insight into the development of a safety case which has been reviewed by the HSE, as part of the voluntary safety case exercise. The sharing of the Amerada Hess experience will be of great benefit to those involved in the development of installation safety cases, particularly in the area of floating production systems.