In-water cleaning can be suitable for removing light fouling
(e.g. the slime layer) with gentle techniques that minimize both the
release of toxic substances from the anti-fouling and the degradation
of the anti-fouling coating system.
Before undertaking any in-water cleaning, check with the
local authorities for regulations regarding the in-water cleaning
of boat hulls and/or the discharge of chemicals into the water column.
If possible, use appropriate technology that captures biological,
chemical and physical debris so that it can be disposed of to an appropriate
onshore facility.
When cleaning an area coated with a biocidal anti-fouling
coating system, use cleaning techniques that minimize the release
of biocide into the environment. In-water scrubbing of large and distinct
biofouling (e.g. barnacles, tubeworms or fronds of algae) generates
waste or debris that may create a pulse of biocide that could harm
the local environment. Biocide in the sediments could affect future
applications by the port authority for the disposal of dredge spoil.
In-water scrubbing may also prematurely deplete the anti-fouling coating
system which would then rapidly re-foul. Scrubbing your craft in-water
is not recommended as an alternative to out-of-water cleaning beyond
the specified service life of an anti-fouling coating system.
Craft with biocide-free anti-fouling coating systems are
likely to require regular in-water cleaning. It is important to use
cleaning techniques that do not damage the anti-fouling coating and
impair its function.