Module 17 - Marine Environment
Anti-fouling and Boat Maintenance
What you will learn
Select a compliant anti-fouling system and use a protect-collect-dispose maintenance sequence that keeps residues out of soil, drains and water.
A product being sold for marine use does not remove the skipper or owner's responsibility to confirm suitability, follow its instructions and contain the waste created during preparation and removal.
Current UK anti-fouling controls are broader than the old shorthand that only TBT is banned. MCA MGN 398 Amendment 1 records that ships must not apply or reapply organotin compounds acting as biocides, and must not apply or reapply anti-fouling systems containing cybutryne. Existing coatings and survey or declaration duties have further vessel-specific provisions, so use a compliant system and obtain competent advice when a coating history is uncertain.
The RYA's practical sequence is Protect, Collect, Dispose. Protect the ground, water, drains, neighbouring boats and people before work begins. Collect wet scrapings, sanding dust, flakes, wash water and contaminated consumables at source. Dispose through the boatyard or local waste route specified for the material rather than leaving rain or wind to move it.
Follow the product's preparation, personal-protection, application and disposal instructions and the yard's rules. Dry sanding, pressure washing, solvents and cleaning products can each create a different exposure or waste stream. 'Biodegradable' or 'eco' marketing does not prove that a product may be released directly into the water; minimise use and keep residues out of the marine environment.
Plan the work area before opening the tin
A yacht is being prepared on a hardstanding near a surface-water drain, and the history of the old anti-fouling coating is incomplete.
1. Confirm
Identify the existing and proposed systems as far as possible, check compatibility and obtain yard or competent advice where the history is uncertain.
2. Protect
Use the required personal protection, ground sheets, screening, extraction and drain controls before disturbing the coating.
3. Collect
Capture scrapings, dust, washings, used abrasives, containers and contaminated protective material at source.
4. Dispose
Keep waste segregated and use the facility or local service specified for that material.
Sense check: If wind or rain could carry residue to soil, a drain or the water, the work area is not yet protected.
Common mistake or limitation
- TBT-only wording is incomplete: current UK controls also prohibit applying or reapplying cybutryne-containing systems.
- Rain, sweeping and pressure washing are transport routes for contamination, not disposal methods.
- A general biodegradable claim does not override the product instructions, yard controls or the need to keep concentrated residue out of water.
Recap
- Current controls cover organotin biocides and cybutryne, not TBT alone.
- Protect, Collect, Dispose turns maintenance guidance into an auditable work sequence.
- Product approval does not permit waste or concentrated cleaning residue to enter water.
Optional quick check
Section 7 of 8
What should happen to anti-fouling sanding dust on a hardstanding?
Sources and factual review
Reviewed 20 August 2026 - Compass Revision editorial review.
Continue studying Marine Environment
This public lesson is part of Revision Module 17. Full revision access adds the guided Learn, Practise and Test flow, flashcards and revision progress.