Coordinator's comments (3) :
We understand that all member countries of the C.G. except Japan do not designate any material as a material which may liquefy by their legislation.
2.3. Method of judgment of the application of the requirements
Japan has developed the procedure for judging the application of the requirements as proposed to the sub-committee. (DSC 2/12/1 and DSC 4/5/5)
In the C.G., we would like to investigate the methods for judging the application, broadly.
Action requested : C.G. members are invited to explain about the method for judging the application of the requirements in your country. Examples of the answer are as follows:
(A) Any problem on the judgment has not been experienced.
(B) There is no special method for judging the application. Judgment of the application of the requirement sometime be problem of ours.
(C) The application of the requirements is judged based on the result of the flow table test or the penetration method.
(D) The application of the requirement is judged based on the comparison of the actual moisture content of the cargo at shipment and its transportable moisture limit.
Australia
Cargoes which are known to liquefy and cargoes which may liquefy during carriage are tested to determine the average moisture content and the Transportable Moisture Limit. Whilst all three methods currently listed Appendix D of the BC Code are acceptable, the Flow Table Method is most commonly used in Australia.
Canada
See item 2.2 above. It is mainly based on the flow table test.
Poland
Before shipment is accepted, actual moisture content of the cargo is checked and its TML is estimated by Flow Table method or the penetration method.
Coordinator's comments (4) :
We understand that the requirement for cargoes which may liquefy is implemented as follows:
(a) If there is any doubt, the requirement is applied to the material;
(b) To determine whether the requirement should be applied or not to a cargo, moisture content at shipment and the T.M.L. are compared.
It is obvious that the method (a) is sufficient to prevent liquefaction and we also recognize the effectiveness of the method (b) for judgment on the application of the requirement. Furthermore, we consider that a method for determining the application of the requirement is needed to make a judgment on materials without experience of carriage onboard. Without the procedure for determining the liquefaction potential, such as the procedure developed by us, in the case that the experience of carriage of the cargo is not enough, the requirement should be applied to the cargo, even if the cargo is supposed to be not liable to liquefy, until the experience will be gained.
3. Investigation of materials suitable for the test for evaluating the liquefaction potential
3.1. Basic understanding
To evaluate the effectiveness of the liquefaction potential test, it is necessary to conduct the tests for various materials.
It is obvious that the result of the liquefaction potential test for typical fine granular mineral concentrate indicates "the material which may liquefy" and that one for very coarse materials such as ordinary iron ore indicates "the material is not liable to liquefy". Therefore, the data obtained by the liquefaction potential test using typical fine granular materials or very coarse materials are not significant in regard to the evaluation of the effectiveness of the test.
Taking these issues into consideration, we would like to look for comparatively fine granular materials which are transported in bulk regardless of moisture content and comparatively coarse granular materials which are subject to the requirements for liquefaction materials, as stated in the terms of reference.
Between DSC 5 and 6, subject to approval for the continuation of its work, we would like to conduct some tests using the materials found through the investigation to evaluate the effectiveness of the liquefaction potential test.
Action requested : C.G. members are invited to take note the above understanding and make comment on this understanding.
