Discuss the following with respect to the AFS (Anti-fouling Systems) Convention.

The International Convention on the Control of Harmful Anti-fouling Systems on Ships (AFS Convention 2001, in force 2008) bans the application and presence of organotin compounds (specifically tributyltin, TBT) as biocides in anti-fouling paints, because of their harmful effects on the marine environment (especially toxicity to non-target organisms and contamination of mariculture). Salient features:

• Prohibition of organotin (TBT) anti-fouling paints; a ship may not bear such paints.
• Requires that any ship applying or bearing organotin be treated: the coating may be coated with a "seal coat"/barrier to prevent the release of organotin compounds or the paint removed; otherwise the ship is not permitted.
• It applies to ships of 400 GT and above engaged in international voyages, and also to fixed/floating platforms, floating storage units and floating production storage units.
• It requires surveys and certification: an International Anti-Fouling System Certificate (AFSC) for ships > 400 GT, and a Declaration on Anti-Fouling System for ships 24-400 m in length? (ships of 24 metres and above but < 400 GT need a Declaration) - to be in force: ships of 400 GT and above international need the AFSC; ships of 24 m or more but below 400 GT need a Declaration.
• Ships are also required to be checked for the anti-fouling system during occasional inspections (e.g. PSC), and the Record of the anti-fouling system is carried.
• Benefits: protection of the marine environment from toxic TBT; reduced contamination of the food chain and mariculture; protection of ship hulls from fouling with newly developed safe coatings while preventing a "false sense of security"; harmonised global standard so ships can trade without conflicting national bans.

Modern TBT-free (copper-based or biocide-free/low-release silicone/fouling-release) antifouling coatings:

• Avoid the environmental persistence, bio-accumulation and high toxicity of TBT; they cause less harm to non-target marine organisms and coastal/mariculture areas.
• Environmentally acceptable - meet the AFS standard and local regulation (e.g. in the EU/US and within special areas requiring low-leach coating).
• Provide long-lasting fouling protection (self-polishing/co-polymer and biocide release) comparable to or better than TBT coatings, reducing fuel consumption, resistance/weight and maintenance.
• Fouling-release (silicone) coatings offer low surface energy and reduced drag, improving fuel efficiency and reducing GHG emissions and hydrodynamic resistance over time.
• Safer for operators (lower toxicity during application) and can be cleaned/regenerated, extending docking intervals.

Vessels of 400 GT and above engaged in international voyages:

• Require an International Anti-Fouling System Certificate (AFSC) issued after survey by the flag Administration or Recognised Organisation.
• The survey confirms the anti-fouling system was not applied, or that no organotin is present, or that the vessel has been treated with an acceptable sealing coat/removal so as not to release organotin compounds.
• The survey is carried out at initial survey (before first issue), at such occasions as repair/renewal of the AF system (e.g. drydocking) with inspection, and an "occasional"/re-establishment survey after significant repairs. In practice, in-water or drydock surveys by the RO at docking intervals verify the coating.
• No statutory periodic renewal such as with SOLAS, but the certificate is issued and renewed at intervals when work affecting the AF system occurs; a signed Record (the AF System data) is attached.
• The certificate must be carried and is checked by port State control.

For ships of less than 400 GT (but typically 24 m or more depending on flag rules) or those not engaged in international voyages, the ship is required to carry a Declaration on Anti-Fouling System instead of a full certificate. This Declaration, signed by the owner or the owner's authorised representative (and in some Administrations verified by the RO), states that the anti-fouling system complies with the AFS Convention (no organotin used). There is generally no statutory inspection required, but the Declaration must be available on board and can be verified at inspections. For all ships (including small and those under 24 m), the fundamental requirement remains that no organotin anti-fouling may be applied, and the "seal coat"/removal option applies for existing vessels.