DNV has presented the most frequent detainable and ISM-related deficiencies identified during PSC inspections of DNV-classed vessels in Q2 2025.
According to DNV, in the 2nd quarter of 2025, 73 DNV-classed vessels were detained. Most of those detentions, more than 80%, were recorded in the Tokyo and Paris MoUs, and the majority of the detentions involved containerships and bulk carriers. A total of 252 detainable deficiencies were recorded during the PSC inspections, leading to 73 detentions.
The details of the deficiency categories are as follows:
The categories of the most recorded detainable deficiencies are shown in the following figure:
A special comment should also be given to the rigging of pilot ladders, which fall under the “Safety of Navigation” category. An incorrectly rigged or broken transfer arrangement poses a significant danger to anyone using it. PSC Officers (PSCOs) may conduct follow-up inspections outside of regular timeframes if they receive information about such deficiencies.
ISM-related deficiencies remain one of the primary reasons why DNV-classed vessels are detained. These deficiencies are not isolated cases but are often the result of multiple other, potentially non-detainable, deficiencies. Collectively, these causes may indicate a broader challenge with the implementation of a vessel’s ISM system.
PSC inspections include checks on the ISM system to confirm that conditions on board and the operation of the vessel align with international conventions and legal requirements. By examining how the ISM system is applied in practice, PSC inspections can help identify systemic weaknesses that could compromise safety or lead to non-compliance.
The Paris MoU, for example, describes ISM-related deficiencies as deficiencies where ”there is a failure, or lack of effectiveness, of the implementation of the ISM Code” (Paris MoU – General principles applied in an inspection, 3.5). If a PSCO in the Paris MoU considers a deficiency to fulfil the above requirement, it is clear grounds for the PSCO to carry out a more detailed inspection. If during such inspection the PSCO concludes that the deficiencies provide objective evidence of a (serious) failure of the ISM system on board, the PSCO will report a (possibly detainable) ISM deficiency (Paris MoU – Guidelines for the Port State Control Officer on the ISM Code, 1.2). Hence, the category “Fire Safety”, for example, may be considered both a “detainable deficiency” as well as an “ISM-related deficiency”. When isolated, a deficiency may be non-detainable, but because it can lead to a deficiency in the ISM system, which in turn can be detainable, it may be an indirect cause for detention.
The following figure shows the most frequent ISM-related deficiencies recorded by category during PSC inspections on board DNV-classed vessels worldwide:
Within these categories, the following sub-categories stand out in their number of occurrences:
Part of maintaining a well-implemented ISM system is clear and consistent communication between the ship and shore teams, alongside a thorough review of reports and audit outcomes.
