Safety of Marine Operations Involving Dynamically Positioned Vessels

Abstract

Dynamically positioned (DP) vessels are widely used in marine operations in the offshore oil & gas industry. The risk caused by DP vessels’ position loss is not negligible, and managing DP safety in marine operations is indispensable. This paper presents an overall framework for DP safety management in offshore marine operations. It consists of the following three key steps, i.e. 1) Identification of position loss scenarios, 2) Risk analysis in terms of position loss frequency and consequences, and risk evaluation, 3) Mitigation of risk via measures to eliminate the risk, or to reduce the likelihood of position loss, as well as to mitigate the consequence in marine operations given DP vessel position losses. Case studies from DP shuttle tankers and DP mobile offshore drilling units are presented to illustrate key principles in each of the above three steps. Quantitative risk analysis and evaluation approach is highlighted, and the associated challenges are described. Recommendations to further improve DP safety management in offshore marine operations are proposed.