Biofouling management


BIMCO's position on "Biofouling management" has been approved by the BIMCO Board of Directors.


In October 2001, the International Convention on the Control of Harmful Anti-fouling Systems on Ships (AFS Convention) was adopted by the International Maritime Organization (IMO). It sets forth requirements to prevent direct adverse impact on the environment from use of anti-fouling systems on ships. In July 2011, IMO also adopted a set of Guidelines to provide a globally consistent approach to managing biofouling reduction. In 2019, a revision of the IMO Guidelines was initiated.

High levels of fouling on a ship's hull and propeller significantly increases its drag resulting in poorer hydrodynamic performance and increased fuel consumption, which has a negative effect on a ship’s GHG emissions. There is therefore a strong economic as wells as an environmental incentive to combat biofouling.

Anti-fouling systems cannot maintain a fouling-free surface, so in-water cleaning between dry-dockings is required. There is a lack of in-water hull cleaning facilities worldwide. Some countries have adopted local regulations on hull cleaning prohibition, thus making in-water hull cleaning very difficult if not impossible.

According to the BIMCO Hull Fouling Clause, if as a result of the charterer’s orders, the ship lies idle for an extended period where hull fouling is likely to occur, the owners’ speed and performance warranty will be suspended until the hull has been inspected and, if necessary, cleaned at the charterers’ expense.

An industry group led by BIMCO has initiated the development of an in-water cleaning standard to enable and increase the quality and safety of in-water cleaning. It will ensure that in-water cleaning can be carried out in an efficient and environmentally sustainable way by ensuring the collection of materials and effluent.

BIMCO’s position

  • BIMCO is concerned about the increase in unilateral initiatives to legislate on biofouling, as they open up for potentially discriminatory and impractical regulations for the industry.
  • BIMCO supports the development of mandatory IMO regulation on biofouling based on the IMO’s guidelines provided ships can be ensured access to in-water cleaning.
  • More areas enabling environmentally sustainable in-water cleaning of hull and propeller should be allowed by coastal and port states.
  • BIMCO supports the development of innovative technologies such as ultrasonic anti-fouling and nano-structured surfaces.
  • BIMCO supports the GloFouling project funded by the UN and executed by the IMO to help implement the IMO guidelines on biofouling in developing coastal states.


Rasmus Nord Jorgensen
in Copenhagen, DK

VPS Bunker Alerts

Veritas Petroleum Services (VPS) publish regular Bunker Alerts based entirely on fuel samples and have kindly permitted BIMCO’s Members to access this information.

The Bunker Alerts are not intended to be an evaluation of overall bunker quality in the port or area concerned, but usually highlight a specific parameter within the fuel which has raised a quality issue.

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