Organisations have advocated the latter course. If this were done on a worldwide basis, vessels everywhere would burn an LSF. After all, the principle is applied on land. Vehicles, aircraft, heating systems and other consumers are supplied with LSFs. The proposal has been met with strong reactions-refineries are not geared to do this in the quantities needed, costs would be incurred and reorganisation required. However, to a limited extent this is happening with the introduction of ECAs in, for example, the Baltic, North Sea and some other coastal regions. There, sulphur in fuel is restricted to 1.5% and this level will be successively reduced to 1% then even further in the course of the next few years. Residual fuel sold for ship bunkers outside the sulphur-controlled zones continues to have a high sulphur content.