Minimum requirements to ice management barrier systems

Abstract

Ice management (IM) is defined as all activities carried out with the objective of mitigating hazardous situations by reducing or avoiding actions from any kind of ice features to a protected unit (e.g. a drilling vessel). The IM activities are risk-reducing barriers. Barriers consist of technical, operational or organisational barrier elements and barrier functions are ranging from ice detection, ice forecasting, ice alerting, physical ice fighting, and disconnection procedures of the protected unit. Operators in Norwegian Arctic waters must comply with regulatory requirements as stated by the Petroleum Safety Authority Norway (PSA) regarding risk management and with requirements as stated in ISO 35104 “Arctic operations — Ice management”. Both ISO 35104 and the PSA regulations require data collection from operations, but information on how to monitor is limited. This paper describes a part of the PSA minimum requirements to barrier systems and a set of Boolean barrier elements for flexible modelling of a wide range of operational IM barrier systems. The Boolean event model may serve as a modular specification of operative barrier systems to include performance requirements and for defining compensating measures for operators if IM barriers are impaired. Further, the Boolean barrier models may serve as specifications for data collection of standardized system and equipment boundaries, functions and failure modes. The IM barrier system model may be the basis for qualitative and quantitative analyses and for verification of the IM systems.