Differences in deficiency types causing ship detentions at the Black Sea Region during the Covid-19 pandemic and pre-pandemic

Port State Control (PSC) is a crucial process that controls the compatibility of ships with maritime standards and regulations. PSC’s duty is to provide a safe and secure maritime environment, as well as the protection of coastal regions, through inspections. After the outbreak of the Covid-19 pandemic, the PSC inspection process, and the number of inspections and detentions, has changed. This study aims to find the most influential deficiency types that cause ship detentions both before and during the pandemic with the Entropy-based Grey Relation Analysis (GRA) method and to study the hidden relationships of deficiency types by examining the frequency of co-occurrence of them with the Association Rule Mining (ARM) method, before and during the Covid-19 pandemic. Detention data was gathered from the Black Sea Memorandum of Understanding (MoU) Region covering the 1st of January 2018–31st December 2021 period. GRA analysis reveals that deficiencies related to Fire Safety and Emergency Systems are found as the most crucial deficiency types for ship detentions in both pre-pandemic and pandemic periods. ARM analysis indicates that there is a strong relationship between International Safety Management (ISM) and Certificate and Documentation (CD) during the pandemic. The findings of this study imply that changes in the PSC regime during the pandemic period led to sub-standard inspections. Based on these results and implications, this study gives recommendations to improve the efficiency of PSC inspections during the pandemic and similar conditions.