Applicability: shipowners, ship operators, ship managers, ship masters, designers, shipbuilders and manufacturers.

The International Convention on the Control of Harmful Anti-Fouling Systems on Ships (AFS Convention) currently prohibits the use of harmful Organotins in anti-fouling paints used on ships.

The IMO has published amendments to the AFS Convention, given in Resolution MEPC.331(76), which come into force on 1 January 2023.

These amendments introduce new requirements that ban the future installation of anti-fouling systems which contain a toxic substance called cybutryne (CAS No. 28159-98-0). The amendments also include requirements for ships that already have installed an anti-fouling system containing cybutryne.

The key amendments include the following requirements:

All ships shall not apply or re-apply anti-fouling systems containing cybutryne on or after 1 January 2023.

All ships* bearing an anti-fouling system that contains cybutryne in the external coating layer of their hulls or external parts or surfaces on 1 January 2023 shall either:

  1. Remove the anti-fouling system; or
  2. Apply a coating that forms a barrier to this substance leaching from the underlying non-compliant anti-fouling system.

The above actions must be implemented at the next scheduled renewal of the anti-fouling system after 1 January 2023, but no later than 60 months following the last application to the ship of an anti-fouling system containing cybutryne.

* Existing coatings on the following ships are excepted from the requirements: 

  1. Fixed and floating platforms, Floating Storage Units, and Floating Production Storage and Offloading installations that have been constructed prior to 1 January 2023 and that have not been in dry-dock on or after 1 January 2023;
  2. Ships not engaged in international voyages; and
  3. Ships of less than 400 gross tonnage engaged in international voyages, if accepted by the coastal State(s).

What should shipowners and ship managers do now?

Operators should ensure that from 2023 only approved anti-fouling coatings are installed that do not include the banned substance cybutryne. Plans should be made for existing coatings that contain cybutryne to be removed or covered with a sealer coat. Details of approved anti-fouling coatings can be found at LR Approvals, by searching under approval category ‘Manufacturers /Workshops Approvals’.

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