Safety equivalence assessment for a small passenger ferry with a periodically uncrewed bridge
针对定期无人驾驶桥楼的小型客轮，提出一种安全等效性评估方法，通过定量风险分析和事件树模型，证明其安全水平不低于现有方案。
A small passenger ferry with a periodically uncrewed bridge creates new opportunities for using waterways for transport of people. The International Maritime Organisation has a guideline for approval of alternative designs. The guideline requires novel concepts to demonstrate a safety level equivalent to or better than existing solutions. Published research on how to use this guideline for a vessel with a periodically uncrewed bridge is however missing. Quantitative risk analysis essential for proving safety equivalence also needs to be advanced. The objective of this paper is therefore to develop a method for performing safety equivalence assessment for this vessel. Existing watchkeeping regulations are used as input to the hazard identification and analysis algorithm developed. A generic event tree model is developed for structuring the accident scenarios enabling risk quantification. Novel and published data are collected and analysed enabling calculating both individual and societal risk which then are assessed against commonly recognized risk acceptance criteria adapted to the analysed use case. When risk is found to be in the ALARP-region, a “delta analysis” is performed to compare the novel vessel with the today’s solution. Risk equivalency is then demonstrated for the small passenger ferry with a periodically uncrewed bridge.