The IMP tributyltin ban - what it means for operators

Citation

(2000), "The IMP tributyltin ban - what it means for operators", Pigment & Resin Technology, Vol. 29 No. 3. https://doi.org/10.1108/prt.2000.12929cab.001

The IMP tributyltin ban - what it means for operators

The IMP tributyltin ban - what it means for operators

Keywords: Anti-fouling paints, Hazardous materials, Biocides, Environment

At the 21st International Maritime Organisation (IMO) Assembly, held in London in November 1999, the draft resolution from the IMO's Marine Environmental Protection Committee (MEPC) proposing that tributyltin (TBT) containing antifouling paints be banned between 2003 (new applications) and 2008 (presence on ships hulls), was formally adopted

There was also agreement that an IMO diplomatic conference, dedicated to antifouling paints be held in 2001, in order to establish a global antifouling convention. This is expected to be the final step in the process of banning TBT containing antifouling paints world-wide, and must go ahead to meet the deadlines set in the IMO resolution (see below).

The critical paragraph in the resolution is as follows:

THE ASSEMBLY AGREES that the legally-binding instrument to be developed by the Marine Environment Protection Committee should ensure a global prohibition of the application of organotin compounds which act as biocides in antifouling systems on ships by 1st January 2003, and a complete prohibition of the presence of organotin compounds which act as biocides in antifouling systems on ships by 1st January 2008.

The IMO's resolve to end the application and use of TBT antifoulings has therefore been clearly stated. Clarification is required concerning the statement "complete prohibition of the presence of organotin compounds which act as biocides in antifouling systems on ships by 15 January 2008". However, options by which this statement may be satisfied could be either:

1. 1.

   applying a suitable sealer coat over existing TBT antifoulings; or

2. 2.

   complete removal of existing TBT antifouling system(s).

The acceptability of alternative (1) will not be known until nearer 2001 and clearly the implications of post sealer application mechanical damage, exposing the underlying TBT antifouling system(s) must also be clarified.

The IMO resolution will obviously have a significant impact on antifouling selection - especially for ship operators contemplating new buildings or major refurbishment of vessels with existing TBT systems. If the complete removal of a TBT antifouling system is required before 2008 then obviously significant costs will be involved in terms of surface preparation, waste disposal, application, new underwater coating system materials and dry-dock time. Therefore, operators should now think very carefully before applying TBT-based antifoulings.

International offers what it believes to be a range of well proven alternatives to TBT antifoulings, which also show reduced environmental impact. For example: TBT free, Intersmooth Ecoloflex SPC products, based on copper acrylate technology claim a successful track record of nearly 5,000 vessels world-wide and are capable of up to 60 months in-service periods. In comparison, the Rosin-based, ablative or controlled depletion polymer (CDP) tin free, antifouling systems offer reduced performance levels over typical maximum in-service periods of up to 36 months. Its biocide-free, Intersleek fouling control products are said to be suitable for fast ferries, and now deep sea scheduled ships - and in the case of the latter vessel category, have reportedly already proven themselves over five year in-service periods, in severe fouling environments.

International's advice remains that ship operators should seriously consider the well proven, tin free or biocide free alternatives now available in the marine market, and gain experience, wherever possible, in order to confirm in-service performance on their own vessels.

Details available from International Coatings Ltd, Tel: +44 (0) 191 469 6111; Fax: +44 (0) 191 438 3711.