A group of carriers have been caught violating the sulfur regulations on several occasions in Northern Europe, and those carriers' violations are often at the more serious end of the scale, concludes a new major study in the Baltic and North Sea.

Several Nordic Universities and authorities are behind the study, which has looked in to the regulations in the so-called SECA zone since its introduction in 2015. The study shows that a small number of vessels and carriers repeatedly violate the regulation.