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Archive: Hull performance management California debates new performance standards

Since September 2011 California State Commission developed new regulations on biofouling which were subjected to several public hearings and reviews and comments by stakeholders. California is proposing — and coatings makers are fighting vividly against — performance standards that would establish a ranking system to determine if a ship’s hull is “clean” enough to enter state waters. The main focus of the proposed regulation is to avoid the invasion of species. After enormous technical efforts to avoid the invasion of species by the release of ballast water, questions arose on the importance of hull fouling, especially in niches like sea chests, rudder, stabilizers etc.

The changes involve amendments the commission is proposing to Article 4.8 Biofouling Management Regulations for Vessels Operating in California Waters (see www.slc.ca.gov).

The standards would apply to new vessels delivered on or after Jan. 1st, 2014, and to existing vessels after completion of their first out-of-water maintenance on or after that date.

The Lands Commission is operating under a statutory directive from the State Legislature to establish regulations “governing the management of hull fouling on vessels arriving at a California port or place.” 

The mandate requires that the fouling plan “must be based on the best available technology economically achievable.” The fouling regulations had to be established by January 2012. Despite four iterations of proposed amendments and consistent and repeated comments by ACA and other industry stakeholders, the CSLC staff remains tied to an “unworkable and scientifically unsupportable idea of numeric performance standards,” ACA said in a release.

The proposed standards would apply to all vessels carrying or capable of carrying ballast water operating in the water of California. Among the draft requirements:
  • Niche areas of a vessel (areas more susceptible to biofouling, such as sea-chests and sea-chest gratings, bow and stern thrusters, fin stabilizers, propellers and propeller shafts, rudders, and out-of-water block marks) must not be “significantly in excess” of 5 % macrofouling (Macrofouling is defined as large, distinct multicellular organisms visible to the human eye such as barnacles, tubeworms, or fronds of algae).

  • All other wetted portions of the hull must not be “significantly in excess” of 1 % macrofouling.

ACA’s working group and others in the industry have urged the commission to delete the performance standards from the proposal and confine its provisions to those in the IMO Guidelines for control and management of ships’ biofouling to minimize the transfer of invasive aquatic species (IMO 2012).

The problem is that the IMO guidelines contain no numerical ranking system of the fouling degree and set up no requirements of tolerable coverage by fouling organisms. The assumed association between fouling degree and the number of invading species in the fouling community can vary indeed and is influenced by numerous factors. Nevertheless, with increasing fouling degree the probability of invading species in the fouling community increases as well.

It is well known that numerical performance standards for the fouling degree on hulls don’t exist up to now. In contrast to standards developed by ASTM or CEPE for simulated field tests on panels. These tests are necessary for the approval of biocides and biocidal products under the regulation of the EU-BPD. But there is no numerical performance test for the hull.

The basic question behind is to avoid the use of ineffective biocides and products. In reality the performance of an antifouling coating depends on the profile of the ship (traded waters, service speed, activity level). Most professional antifoulings are designed and recommended by paint manufacturers under these auspices. If the profile of the ship is changed due to new charter contracts or missing contracts, the antifouling coating may not perform as intended. But hull management is actually driven by aspects of fuel consumption and reduction of emissions. Taking into account the fact that even microfouling increases the probability of invasion as well as friction and fuel consumption/emission, ship operators are more and more interested in “clean hull condition”.

The approach of the California initiative raises fundamental and important questions which are up to unresolved but necessary to clear right from the approval scheme to the practice in service.




IMO (2012): Guidelines for the control and management of ships’ biofouling to minimize the transfer of invasive species.

Paint Square News, June 27th, 2012  



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