Bulk Carrier Guide Online
Bulk Carrier Guide Online
Home ||| Bulk Cargo ||| Planning ||| Care ||| Safety||| Self unloaders

Sampling and Testing of Bulk Cargo,Decision to Load & Awareness During Loading

Sampling and testing procedures for bulk cargoes that may liquefy should be carried out to international standards such as the test procedures described in Appendix 2 of the IMSBC Code.

Flow Moisture Point – the maximum water content, expressed as a percentage, at which a sample of cargo will begin to lose shear strength. Cargoes with moisture content beyond FMP may be liable liquefy.

Transportable Moisture Limit - is defined as 90% of the FMP. From the ship operators and master’s perspective the important figures for the laboratory to determine are the TML of a representative sample of the cargo to be loaded and its actual moisture content. It is a requirement of SOLAS that the average moisture content of any type of granular cargo in any cargo space must not be higher than the TML. This is an important point; it is of little use to the vessel if an average moisture content of all cargo is provided. This may lead to dry cargo in some holds and cargo liable to liquefy in others which will put the vessel at risk.

In order to find the TML the laboratory must first determine the FMP of the sample using one of the prescribed techniques.

Loading a cargo above, at or near its FMP represents an unacceptably high risk for vessels and for this reason a safety margin is allowed – this gives the TML.

After determining the FMP the moisture content of the cargo is obtained by drying samples of the cargo in accordance with Section 4.6.4 of the Code.

If the moisture content of the cargo sampled is below the TML then the cargo should be safe to load.

However, there is no way for the vessel’s operators or master to determine whether or not the sampling and testing procedures used by shippers are adequate and/or accurate. In some cases such as with some nickel ore cargoes, the subject of their own briefing, not only can the techniques used for testing be deficient, but also the inhomogeneous nature of the cargo itself makes FMP determination using the techniques described in the IMSBC Code problematic as they are designed for more homogeneous cargoes.

Can Test

Bulk cargo can test 1
Fig:Bulk cargo can test -stage 1( before )
In order that the vessel can make its own assessment of the likelihood of the cargo to liquefy the IMSBC Code describes a shipboard method known as the “can test”. Master’s can refer to the IMSBC Code (2009 Edition), Section 8, page 33, for details. The test involves filling a small can with the sampled cargo and repeatedly banging it on a hard surface. The appearance of the material at the end of the test can be used to form an opinion regarding the suitability of the material for shipment.

Bulk cargo can test 1
Fig:Bulk cargo can test -stage 2( During )
This test should not be a substitute for proper laboratory testing using an appropriate methodology. However, if can tests carried out on a cargo presented for loading indicate a propensity for liquefaction, this is a major warning sign that the cargo as a whole may be unsafe for carriage.
Bulk cargo can test 3
Fig:stage 3( after a failure on this occasion )
Expert advice should then be sought. If shippers present significant amounts of material that fails the can test, this is an indication that the cargo as a whole is unsafe, and that documentation provided may be flawed. It should also be borne in mind that a negative result from the can test (i.e. no free moisture or fluid condition is seen) does not necessarily mean that the cargo is safe for shipment.

Advice to Owners and Masters on Loading

Although it is the shipper’s duty under SOLAS to test and certify that a cargo is safe to load experience has shown that in some cases this does not always occur. Therefore, the actions of owners and masters before arrival and, most importantly, at the load port are crucial in ensuring that a vessel is protected from loading a cargo that may liquefy. Masters and ship operators should always bear in mind the possibility that the information contained within the shipper’s declaration, for whatever reason, may not accurately reflect the true condition of the cargo.

Documentation and Information

Members must ensure that cargo interests have provided the necessary cargo documentation, that the information is up to date (moisture content should be taken within 7 days of loading for cargo that may liquefy) and takes into account any recent events (e.g. heavy rain) that may change the characteristics of the cargo.

The master should be made fully aware of the characteristics of the cargo to be loaded. The provision of the information to the vessel should ideally take place well in advance of loading to enable the master to prepare for the planned loading, including the appointment of surveyors and or cargo specialists to protect Member’s interests if thought necessary.

Master to be aware of any known problems with a particular cargo or of any recent abnormal precipitation at the load port or point of origin of the cargo. There are no circumstances in which it is considered prudent to load cargo liable to liquefy without first having received the appropriate cargo documentation relating to the cargo to be shipped on that vessel i.e. a properly completed shipper’s declaration, and a signed TML and moisture content certificate indicating that the cargo is safe to load.

Decision to Load

The master’s decision to commence loading is critical in avoiding the problems associated with cargoes that liquefy. High loading rates mean that vessels can have many thousands of tonnes of cargo loaded in just a few hours.

To safeguard a vessel and its crew and to avoid the delays, disputes and other problems associated with discharging a cargo that is unsuitable for transportation the master must satisfy himself, as far as can be reasonably determined, as to the suitability of the cargo for loading. If at all practicable the master should arrange to view the cargo stockpiles to be loaded onboard as the condition of the stockpiled cargo may indicate potential problems with liquefaction. Samples collected from these stockpiles may be Can Tested for signs of liquefaction before loading.

Where doubt exists as to the characteristics of the cargo to be loaded the master should delay the start of the loading operation and contact his owners. In such circumstances it is advisable to appoint an independent surveyor or cargo specialist for advice. Always remember that removing unsuitable cargo from the vessel can be highly problematic. In the case of cargoes known to liquefy and which have resulted in problems for vessels, e.g. iron ore fines ex India during the South West Monsoon season, it will be to owners’ advantage to appoint independent surveyors to sample and inspect the cargo to be loaded prior to a vessel’s arrival and to assist the master throughout the load.

Awareness During Loading

As the first cargo comes aboard the vessel the master and his officers should endeavour to take samples and test them using the Can Test as described in Section 8 of the IMSBC Code. Ideally, further such testing should take place at regular and frequent intervals during loading to ensure that the condition of the cargo coming onboard is safe throughout the loading operation. The location of the sample may be critical. A wet cargo exposed to sunshine for a few days may be dry on the surface but still have a high moisture content at the base or at intermediate layers. It is therefore important that a cross section of the cargo is sampled.

The characteristics of the cargo within the hold should also be monitored for signs of excess moisture. Cargo monitoring throughout the loading operation is necessary to try to detect cargo that may liquefy being loaded. Where a master is in any doubt as to the suitability of the cargo for transportation loading should suspended, owners informed, the Association contacted and an independent surveyor or cargo specialist called in to assist the master with the further assessment of the cargo. Weather conditions during the load may also require the suspension of the loading operation. Loading cargoes liable to liquefy during heavy rain is an unnecessary risk. Where the vessel is engaged in carrying a cargo that is not listed in the IMSBC Code then Section 1.3 of the Code should be followed.

Cargo Unsuitable for Shipment Already Aboard

Suspect cargo should be sampled by an independent laboratory and, if found to be beyond its TML, then the safest option is to discharge the cargo. This sounds simple but unfortunately experience has shown that once a vessel has loaded wet cargo getting rid of it at the load port can be highly problematic for the vessel.

Commercial reluctance on the part of the shippers and ports to accept/unload the unsuitable cargo can lead to severe delays and larges costs. In the worst cases these situations can drag on for months. There may also be damage to valuable commercial relationships should such a dispute arise. It is always best for the vessel’s safety and in the owner’s interest that iron ore fines unsuitable for shipment are identified before they come onboard.

Our detail pages illustrated many safety aspects of Bulk carrier

Home page |||Bulk carrier types ||| Handling of bulk coal |||Cargo planning ||| Carriage of grain |||Risk of iron ores |||Self unloading bulk carriers |||Care of cargo & vessel |||Cargoes that may liquefy |||Suitability of ships |||Terminal guideline |||Hold cleaning |||Cargo cranes |||Ballast handling procedure |||Bulk carrier safety |||Fire fighting systems |||Bulk carrier General arrangement

Operation of sea going bulk carriers involved numerous hazards . Careful planning and exercising due caution for all critical shipboard matters are important . This site is a quick reference to international shipping community with guidance and information on the loading and discharging of modern bulk carriers so as to remain within the limitations as specified by the classification society.
It is vital to reduce the likelihood of over-stressing the ship's structure and also complying with all essential safety measures for a safe passage at sea. Our detail pages contain various bulk carrier related topics that might be useful for people working on board and those who working ashore in the terminal. For any remarks please Contact us

Copyright © 2010 www.bulkcarrierguide.com All rights reserved.

Although every effort have been taken to improve the accuracy of content provided the publisher of this website cannot gaurantee for errors. Disclaimer Privacy policy Home page