Proceedings of the

The 33rd European Safety and Reliability Conference (ESREL 2023)
3 – 8 September 2023, Southampton, UK

Evaluating Differences between Maritime Accident Databases

Spencer A. Dugana and Ingrid B. Utne

Department of Marine Technology, NTNU, Norway.


Maritime accident statistics are used as a key part of the IMO's formal safety assessment (FSA), a risk assessment methodology to guide policy decisions in the maritime industry. Under-reporting of maritime accidents can inhibit the accuracy of results derived from the FSA, therefore having a direct influence on maritime policy. The objective of this work is to perform comparisons between accident databases, and to investigate the degree to which underreporting is biased by factors including the type of accident, degree of severity, and ship type. This study analyzes databases of reported maritime casualties from 1) IMO GISIS, 2) IHS Fairplay, and 3) the United States Coast Guard CGMIX. The databases are subset to an eight-year period and for commercial ships greater than 100 gross tonnage (GT) to enable a direct comparison. The reporting rates for the GISIS and IHS databases are calculated for accident type, accident severity, and ship type. Results indicate that the GISIS and IHS databases contain significantly fewer non-serious accidents than serious accidents. Further biases were observed by accident and ship types. Founderings, fires / explosions, and strandings are more likely to be reported than other accident modes. Hull / machinery damage is the accident mode with the lowest reporting rate.

Keywords: Maritime accidents, Under-reporting, Reporting rate.

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