Australia and Brazil have implemented a new schedule to the International Maritime Solid Bulk Cargoes Code reclassifying sea-borne iron ore cargoes, according to a circular published by The International Group of P&I Clubs on January 23.

The move would see mining majors Vale, BHP, Rio Tinto and others re-categorizing their iron ore cargoes to meet the new requirements.

Market sources surveyed by Platts Monday said the amendments were, however, unlikely to have any immediate commercial impact on cargoes shipped out of Brazil and Australia.

As per the amendments, whether or not an iron ore cargo should be categorized as iron ore fines is to be determined by the goethite content of the material and its particle size distribution.

Cargoes re-categorized as iron ore fines, or Group A cargoes under the IMSBC Code, are required to be tested under a new procedure to determine the transportable moisture limit, or TML.

Shippers are also required to comply with specific weather precautions for Group A cargoes, including ensuring that the moisture content of the cargo is maintained at less than its TML during loading operations and voyage.

These amendments were agreed upon in a September 2013 meeting of the International Maritime Organization's Sub-Committee on Dangerous Goods, Solid cargoes and Containers, and detailed in an IMO circular dated November 15, 2013.

It was decided at the time that these amendments would come into mandatory effect from January 1, 2017, although signatories to the Safety of Life at Sea Convention 1974 were invited to undertake early implementation voluntarily.

Brazil implemented the amendments on December 27, 2013, followed by Australia on January 1, 2014.

Brazilian miner Vale has re-categorized its iron ore fines mined from Carajas, Brazil, as Group A cargoes, the IG P&I said in its circular.

Cargoes with a minimum of 35% goethite content by mass are classified as Group C cargoes, meaning these are neither liable to liquefy nor to possess chemical hazards.

In terms of particle size distribution, cargoes containing 10% or more fine particles less than 1 mm in size as well as 50% or more particles less than 10 mm in size are classified as Group A cargoes, meaning these cargoes may liquefy if they are shipped at a moisture content exceeding their TML.

But should these cargoes have more than 35% goethite content by mass, they would be classified as Group C cargoes for the purpose of sea transport.

In general, the TML for iron ore fines is about 15%, as previously reported.

The amendments came about following a research project undertaken by Rio Tinto, BHP Billiton, and Vale to analyze the behavior of iron ore fines cargoes carried by ships, the IG P&I said.