Risk Identification and Assessment for the Offshore Demonstration of Submarine Cables

Offshore demonstration of submarine cables is conducted under uncertain marine conditions and complex offshore operations, requiring a systematic risk assessment. This study divides the demonstration process into four phases (loading/unloading, transport, installation/decommissioning, and offshore testing/maintenance) and identifies potential hazards through expert workshops. Hazard items were first identified using a checklist-based review and a task-based hazard identification (HAZID) workshop, in which offshore work procedures were decomposed into step-by-step tasks and potential accident scenarios were derived. Based on these identified hazards, the analytic hierarchy process (AHP) was applied to evaluate the relative risk level of each phase, and a risk matrix (Likelihood–Severity, LS) was used to assess the risk level of individual hazards. The AHP results indicate that the installation/decommissioning phase poses the highest risk (36.9%), followed by offshore testing/maintenance (29.1%), transport (22.6%), and loading/unloading (11.4%). In the LS analysis, cable damage during installation/decommissioning and lightning strikes during offshore testing/maintenance were evaluated as the highest-grade hazards. These findings provide a risk profile that spans the entire offshore demonstration cycle of submarine cables and offer a basis for prioritizing safety management, allocating resources, and planning operational procedures.