Emerald Group Publishing Limited
Copyright © 2000, MCB UP Limited
The TBT ban for antifoulings
Keywords Anti-fouling paints, Environmental impact, International coatings
A worldwide ban on tributyl tin in marine antifoulings is due to be in place by 1 January 2003. A number of press reports, particularly in the marine press, have suggested that all present alternatives to TBT do not work. A statement from International Coatings Ltd of Gateshead, UK, a world leader in marine coatings, says that this is incorrect.
International Coatings gives the example of its tin-free Intersmooth Ecoloflex SPC antifoulings which are based on self-polishing, copper acrylate polymer technology and are said to be suitable for up to 60-months in-service periods, as opposed to the rosin-based, ablative tin-free products, which are typically only suitable for up to 36-months drydock interval. The Intersmooth Ecoloflex SPC products contain biocides which show reduced environmental impact compared to TBT.
International Coatings claims that Intersmooth Ecoloflex SPC products can give equivalent performance to TBT SPC coatings, proven through its experience on over 1,200 deep sea and over 2,000 coastal applications (full ships). Therefore the company does not oppose the dates for the TBT ban agreed in the draft International Marine Organisation (IMO) assembly resolution at its meeting in London last summer. Their advice to ship operators is to gain experience with antifoulings such as Intersmooth Ecoloflex SPC antifoulings to confirm in-service performance for themselves on their own vessels.
At the London meeting, which was the 43rd meeting of the IMO's Marine Environmental Protection Committee (IMO-MEPC43), delegates agreed that a legally enforceable ban on antifoulings containing TBT by 1 January 2003 is best achieved by adoption of a "free-standing" IMO convention specific for antifouling products. This convention will be independent of existing IMO conventions and will also contain a mechanism to ban other products in future if they are deemed unacceptable for the marine environment. If a global TBT ban is to be legally enforced by 1 January 2003 as agreed, it is imperative that the final text for the new antifouling convention is agreed by MEPC and presented to a diplomatic conference of IMO in 2001 at the latest. After discussions in the plenary session of MEPC43, a "roll-call" vote was taken of country delegates and a majority decision taken to proceed and convene an IMO diplomatic conference in 2001 to ratify an antifouling convention.