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5 April 2004, 04:52 pm
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International Maritime Organisation

The International Sailing Federation (ISAF) submitted draft Guidelines in support of Regulation A 5 to MEPC 49 under cover of MEPC 49/2/7. Since then there have been some significant changes to certain parts of the Convention, now in its final format.
ISAF have revised the Guidelines and these were submitted informally to the WG at MEPC 51. It was agreed that these would be circulated so that comments could be made in an Informal Correspondence Group. The revised draft is attached.

ISAF hopes that these Guidelines provide a simple system for identifying to Port Officers the vessels which qualify for Regulation A5 treatment and a "stand alone" guide for the user to Ballast Water Management procedures which are acceptable.

It might be helpful to give some explanation of the use of Ballast Water in a Sailing vessel. The dynamics of ballast water trim are different from those to be found in power driven commercial vessels. It is necessary for the trim and stability of a sailing yacht designed or constructed to use ballast water for the ballast to be trimmed as frequently as the direction and force of the wind changes. A sailing yacht will periodically alter course to bring the wind from one side of the boat to the other, a process called tacking. Ballast water on pleasure yachts may be continually pumped in and out and transferred from side to side as the boat tacks and the wind changes. Typically 60ft. boats of the type that undertake round the world sailing (Volvo 60's) have 4 tonnes of ballast water; larger boats have 6-8 tonnes; others have 4 tanks of 1.5 tonnes. A yacht may be changing tacks 6-8 times a day and sometimes 20-30 times. The number of tacks may well be less in a large cruising yacht on an ocean passage.

Whenever a sailing yacht tacks the ballast water will have to be transferred from tanks on the windward side of the hull to the other. In most boats part of the transfer will be by gravity and the rest will be taken up from the sea. The surplus in the tanks that have newly become on the leeward will be discharged. This process will be repeated each time the vessel changes tack. Whenever the wind moves aft the yacht will discharge most of the ballast water from all tanks to lighten the hull. In contrast a tanker, bulk carrier or other powered vessel using ballast water for stability will trim its ballast water tanks only when cargo is loaded or discharged. Dependent on the weather conditions it is possible that at least 95% of the ballast water carried by a sailing yacht will have been wholly exchanged in the first hours of any passage.

The Guidelines provide that Exchange is the primary form of control, the suggested procedures take account of the peculiar dynamics of sailing. It will be difficult because of space constraints to use mechanical or UV treatment to produce ballast water that satisfies the Convention standard. Filtration will not be practicable, as the small size of the filters will delay the transfer time between tanks.

The small quantity of residual ballast water remaining after a passage will have to be chemically treated. ISAF recognizes that the availability of chemicals for use will change over time as research continues. The guidelines have been drafted bearing this in mind and rely on the IMO Approval procedure. In due course ISAF would issue a list of approved Chemical available for use by Recreational Vessels.

Regulation A5 also applies to the very small number of pleasure yachts, which use Ballast Water and rely solely on power as a means of propulsion. These may have the facility to use 'big ship' means of Ballast Water Management. The draft makes it clear that such means are not precluded even if the ship is within the Regulation A5 size parameters.

ISAF would welcome any comments of this draft All feedback should be sent to Michael Devonshire via the ISAF Secretariat. A final draft is intended to be submitted to MEPC 52 and responses by 28 July would be appreciated.
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