HFO is the world’s dirtiest and most polluting ship fuel”, a residual waste product from the oil refining process that resembles tar. Ships use HFO as a fuel because it is relatively cheap, particularly for larger vessels (like containerships and tankers). Combusting HFO produces high levels of pollutants, particulate matter, black carbon, sulphur oxide and nitrogen oxide, each of which are linked to an increased risk of heart and lung disease. As Arctic waters become increasingly navigable, more vessels that carry HFO are passing through. Other risks associated with the use of HFO in the Arctic include threats to the food security, livelihoods and way of life of Arctic communities; risks to the Arctic marine environment; and harmful emissions that negatively impact the local and global climate”. Surprisingly, the Polar Code (see definition), which was a set of regulations that imposed stricter regulation for shipping in the Arctic, did not impose bans on the carrying or use of HFO, only discouraging it. Only in April this year did the IMO (see definition) call for the rapid implementation of a ban, set for 2021.