Merchant shipping transports almost 90 % of the goods that are bought and sold across the world. Within the logistics chain of global freight transport, the human factor plays a key role in ensuring that the vessels reach their destinations without major problems, because behind all the onboard technology there are a large number of people both on board the vessels and ashore.

Most of the studies published relating to marine accidents conclude that human error is mainly responsible for such accidents, up to 70-80 % of them. However, "the conclusions of many of these studies do not go any further, and do not explore who the people involved in the cause of the accident are, whether they are crew members or other parties, such as shore and port staff, inspectors, shipping company staff, etc. So, it is interesting to explore whether these mistakes were made by the crew members on board the stricken ships simply due to mental fatigue as a result of having been on board for too long, for example, or whether the mistakes arose as a result of misunderstandings between the crew members and shore personnel, etc.", said Javier Sánchez-Beaskoetxea, lead author of the study and lecturer in the Department of Nautical Sciences and Marine Systems Engineering at the UPV/EHU.

"In this paper, based on the reports of a large number of accidents published by the US National Transportation Safety Board between June 1975 and September 2017, we tried to determine what percentage of human error could be attributed to the crew or other people, and we also presented a detailed classification of the type of human error," explained Sánchez-Beaskoetxea.

Downward trend

"The results show that when crew error plus non-attributable crew error are added together, the total percentage of accidents attributable to human error is 75 %, which is similar to that found in the literature reviewed," said the lead author of the paper. However, "the percentage of human error for which the crew was responsible is 46% of all the accidents analysed. So, human error in shipping accidents is not always crew error. The crew is to blame for less than fifty percent of human error," stressed the UPV/EHU researcher. "Other factors have to be taken into account: technical failures, and mistakes made by the people working around the vessels (shore and port staff, inspectors, shipping company staff, etc.).  For example, if the pilot who assists the ships in port gives you bad advice and an accident occurs, the responsibility does not lie with the crew," said Sánchez-Beaskoetxea.

Yet "some interesting findings emerge in the study if we look at human error on different types of vessels. For example, human error on cargo and passenger vessels is 82%, but crew error is only 43%. Human error extends mainly to pilots because the ship is exposed to greater risk when navigating narrow channels or during berthing/casting off. Pilots are some of the most important people in shipping safety, they are the ones who give advice, but they do not belong to the crew," said Javier Sánchez-Beaskoetxea. "Human error on fishing vessels is 51% and crew error is almost 47% in all cases; however, crew error on tugboats increases to almost 58%," he added.

In the short and medium term, the research group intends to conduct a similar study based on reports from other countries that also have a large number of published cases, such as the United Kingdom, in order to compare whether the conclusions that have emerged in this study could also be extrapolated to other countries.