Maritime shipping is one of most efficient modes of transport today. With the growth in world trade, ship traffic in the world’s oceans has greatly increased over the past few decades, making maritime safety increasingly challenging. Safety in maritime transport includes various aspects such as human safety at sea and at port, and also environmental safety and sustainability. In order to enhance navigational safety and prevent collisions at sea, several navigational rules have been developed over the past 40 years. In 1972, the International Maritime Organization (IMO) published the International Regulations for Preventing Collisions at Sea (COLREGS), which set the international rules of the road for maritime navigation.
Despite the considerable effort by the maritime authorities, safety is still a concern especially in heavy traffic areas. The European Maritime Safety Agency (EMSA) has reported 20,616 marine casualties and incidents worldwide from 2011 to 2017. Globally, the combination of collision (23.2%), contact (16.3%), and grounding/stranding (16.6%) shows that navigational casualties represent 53.1% of all casualties with ships. Furthermore, human error is found to be behind 75% of 15,000 marine liability insurance industry claims analyzed by Allianz Global Corporate & Specialty (AGCS). It is worth noting that an incident involving a fully loaded ultra-large container ship can easily result in a US$1bn–$2bn insurance claim, including damage to cargo, hull, salvage and wreck removal costs.