Bow-Tie Risk Model

A risk-assessment diagram that places a single hazardous event (the knot) at the center, maps the threat causes on the left and the consequences on the right, and shows preventive barriers on the cause legs and mitigating barriers on the consequence legs. Used in maritime security and SMS work to make controls explicit for events like a piracy boarding or a cargo fire, it traces directly to ISM Code risk-management practice and ISO 31000 principles. Each barrier names an owner and a degradation factor.