Short Review of Customer-made Fouling and Damage
Prevention
Systems for Ship Hulls and Associated Technologies
LimnoMar
Last update February 2020
The following should deliver a rough overview of the fouling prevention system in use and on the
market to demonstrate the most dominant systems and those of minor application. Unique fouling
prevention solutions are rare, if existing at all. The selection of an effective and vessel-tailored
fouling prevention system should fulfil the following criteria: Minimal fouling on current exposed hull
areas and in niches to achieve optimal performance, biosecurity and access to global ports. As
integral part of biofouling management it will reduce emissions, fuel and costs on the long run.
Biocidal SPCs/CDPs
Effective after recommendation by respective paint company according to a defined and constant
operational profile of vessel 60 – 72 months (low to high activity, global waters, restricted lay-off
periods)
Effective after recommendation by respective paint company according to no defined and varying
operational profile of vessel, has be combined with regular in-water cleaning after a couple of month
depending on activity level, traded waters and service speed, appropriate, smooth cleaning may only
remove the leached layer
Precautious measurements: Additional paint layers may have to applied to compensate abrasion due
to cleaning
Products: More than 1,400 registered at Lloyds List, standard fouling prevention systems
Biocide-free SPCs
Exclusively effective after recommendation by respective paint company according to clearly defined
operational profile of vessel which will be kept 60 months (low to high activity, global waters,
restricted lay-off periods)
Products: One product of one company with four variations related to operational profiles of vessels
Foul Release Coatings, biocide-free
Effective after recommendation by respective paint company according to operational profile
preferably for vessels with high activity, high service speed and short lay-off periods (ferries, offshore
service vessels, container ships with predictable operational profile
Effective without damage over 60 months
Vessels with varying traded waters, low service speed, low activity level and extended idle periods
regular softly cleaning necessary to avoid biofilm formation and stronger adhering bryozoans and
tube worms
Due to fragility mechanical impact protection by oversized fenders (cruise ships), or lateral protecting
bulges (ferries), no service in drifting ice
Fig. 1 Foul release coatings, silicone based
Fig. 2 Oversized fenders to protect foul release coatings in port
Fig. 3 Lateral bulge to protect the hull and underwater hull coatings on ferry
Foul Release Coatings, biocidal
Foul release coatings, based on silicone backbone with incorporated biocide in extruding hydrogel
Effective after recommendation by respective paint company according to operational profile
recommended for vessels with low activity, low to medium service speed and extended lay-off
periods (bulkers, tankers, cruise ships)
Effective without damage over 60 months
Due to fragility mechanical impact protection by oversized fenders (cruise ships), or lateral protecting
bulges (ferries), no service in drifting ice
Products: 2 products
Mechanical Impact Coatings
Glass fibre or glass balls enforced epoxies
At boot-top for vessels with extended container ships, bulkers, tankers with frequently varying
loaded draught and for flat bottom of vessels operating near soft sediment seabed
Fig. 4 Fender damage on boot-top coated antifouling paint, container ship
Fig. 5 Damage on boot-top coated with antifouling paint, tanker
Fig. 6 Mechanical damage (abrasion on flat bottom of vessel operating in shallow waters near or in contact
with soft bottom of seabed
Vessels with large boot-top area: Container ships, tankers, bulkers
Products: Couple of products frequently in use with antifouling paint on top
Hard coatings without any foul release properties
Glass fibre or glass globules enforced epoxies, no different to most of anti-corrosive paints, some
with ice-class
No inherent fouling protection, coatings have to be cleaned weekly, otherwise strongly adhering
macrofouling will develop which can be removed either by abrasion of the upper layer of the coating
or by hydro-blasting (min. 1,000 bar) with remaining base plates of barnacles and basic attachment
of other fouling organisms
Recommended for fresh water or vessels with defined operational profile permanently trading
between fresh-, brackish- and sea water, vice versa at high activity
Fig. 7 Hard coating after one year in service, before cleaning
Products: 3 -4 products, offered as cleanable coatings, essentially not different from glass fibre
enforced anticorrosive epoxy coatings
Hard Coatings with foul release properties
Hard coatings which withstand impact of cleaning by rotating brushes or hydro-jetting but possessing
inherent properties to reduce the adhesion of fouling organisms
Can be cleaned and should be cleaned according to in-water inspections and foul degree, most
favourable to be cleaned in the biofilm stage
Products: 2 products
Cleaning Technologies
Cleaning without any collection and filtration
Majority of in-water cleaning companies use diver steered cleaning tools with rotating brushes with
different stiffness
More than 30 companies globally active
Cleaning with own collection and filtrations system
An increasing number of in-water cleaning companies use divers steered cleaning tools with rotating
brushes or ROVs using hydro-jetting. Collected fouling is concentrated in a bag or pumped to a
filtration and treatment unit
Approx. 6 companies globally active
Fig. 8 In-water cleaning toll with rotating brushes, collection- and filtration system
Filtration Technologies in combination with In-Water Cleaning
Ballast water treatment facilities on board or mobile systems which can be moved inside of ports or
between adjacent ports
Systems which meet the D2 standard and are certified will offer the most sophisticated filtration
technology.
To avoid connectivity problems between cleaning tools with collection systems via water draining
tube, it may be an option to pump the water with the removed fouling organisms in a barge, one
shell tankers out of service etc. To pump the effluents in an intermediate storage would either allow
to collect water from several cleaning actions or in cases when the amount of water to be filtered is
to voluminous to get ready before the vessel has to leave the port
Fig. 9 Mobile blast water treatment facility
Marine Growth Protection Systems (MGPs) for niche areas
If accessible sea chests, thrusters and stabilizers are coated with those antifouling paints as applied on the hull
In addition cathodic protection, ultrasound and enclosure systems for the cooling system to be filled in port
with hot water, preferably freshwater
Products using copper anodes: 3 at the market
Products using ultrasound, UV-light and heat: 10 products