Antifouling rules: is copper antifouling still allowed, and what are the alternatives?

Questions about an antifouling ban usually mean copper, and what is still allowed. The position is clearer than talk on the pontoon suggests: antifouling is a biocidal product and may only be sold and used if it is approved. In Great Britain the Health and Safety Executive is responsible for biocides, in the EU the national authorities under the Biocidal Products Regulation. Copper compounds are approved active substances, so an approved copper antifouling is allowed and not banned as such.

Tin based paints such as TBT are a different matter. They were restricted after damage to shellfish and then banned worldwide by a convention of the International Maritime Organization. An older boat may still have traces under many layers, so take care when stripping and keep the dust out of the water. Why antifouling at all? Weed, barnacles and mussels slow the boat, raise fuel use and block cooling water intakes and the log. How much growth you get depends on the area: warm salt water grows far more than many inland waters.

Local rules come first. Some harbours, inland waters and countries restrict biocidal paints further or require hulls to be cleaned, so ask the marina, the club or the navigation authority before painting, and ask again when you keep a yacht abroad. The alternatives include hard coatings scrubbed several times a season, silicone foul release coatings, antifouling wraps, ultrasonic systems, boat wash stations in some harbours and dry stack storage. Whatever you choose, sand only with extraction, on a wash down area with a trap, and dispose of residue as hazardous waste.

Worth remembering

Check the local rules first, then choose the paint.