A third generation of antifouling coatings has been introduced, a series
that is certain to last the required five-year interval between drydockings,
and can therefore compete with tin-based products.
Tin-based antifouling coatings have proven an effective and economical means of protecting underwater hulls, but tin has been found to have harmful effects on marine life in coastal areas; it not only keeps algae and barnacles from attaching to the bottoms of ships, but also impacts on other marine organisms. This led to the introduction of a ban on tin for boats under 25 meters in the western world in the 1980s, and work has been under way ever since to develop new tin-free coatings that can improve the environmental performance of larger vessels too. The International Maritime Organization (IMO) is pushing for a complete ban on tin-based antifouling coatings; a draft resolution has been tabled for a complete ban on the application of coatings containing tributyltin (TBT) from Jan. 1, 2003, and for all TBT-based coatings to be removed from all vessels by 2008.