Moisture Management Plans for Group A cargoes: Two steps to ensure compliant shipping
Group A cargoes are defined as cargoes which may liquefy or undergo dynamic separation if shipped at a moisture content in excess of their transportable moisture limit (TML). For a Group A bulk cargo, controlling moisture is therefore a critical part of safe shipment to avoid catastrophic stability and structural risks to the vessel. Under SOLAS regulations and the IMSBC Code, cargo that exceeds its TML shall only be accepted for loading if the ship is specially constructed or fitted for carrying liquid-behaving bulk materials. The IMSBC Code requires the shipper to establish documented, systematic procedures in the form of a Moisture Management Plan (MMP) to ensure that Group A solid bulk cargoes are sampled, tested, managed, and loaded at a moisture content strictly below their TML.
Under paragraph 4.3.3 of the IMSBC Code, these procedures must be approved by the Competent Authority at the port of loading. But approval is only the first step. The plan must then be followed in practice, and each shipment must be supported by current moisture and TML certifications before loading.
What a Moisture Management Plan needs to contain
The International Maritime Organization (IMO) provides detailed guidelines which outline the required procedures for sampling, testing and controlling moisture to ensure full compliance with the IMSBC Code (MSC.1/Circ.1454/Rev.2 issued June 26, 2023). An MMP should be prepared in accordance with the IMO guidelines and should address, in substance:
Sampling: how representative samples are drawn from the stockpile or cargo stream. The sampling method employed must be appropriate for the material and the form in which it is available (e.g. stockpile versus moving stream) to ensure that the sample tested at the laboratory is as close as practicable to the cargo to be loaded.
Testing: Careful attention must be given to the testing methods, particularly when establishing the TML. The IMSBC Code provides various test methods tailored to specific material characteristics (e.g., the Flow Table test or the Proctor-Fagerberg test etc). Engaging qualified experts who have the specific technical know-how to choose the right test for your cargo is therefore paramount
Moisture control: Effective moisture management between sampling and loading completion is critical to ensuring the cargo remains safe. This requires strict oversight of stockpile conditions, active drainage, immediate responses to adverse weather, and clear triggers for re-testing. These continuous controls guarantee that the actual moisture content remains strictly below the TML right up to the point of loading.
Roles, records and frequency: Identifying who is responsible for each step, how results are documented and reported, and how often testing and monitoring occur.
The plan is the backbone of the whole process. Everything that follows - the certificates and the declaration to the Master- should follow the plan.
Two separate steps: approving the procedures, and certifying each shipment
There are two distinct steps required to ensure compliance, on two different timelines:
Step one: approval of the MMP
The MMP is submitted to the Competent Authority (in Australia, this is the Australian Maritime Safety Authority (AMSA)); AMSA reviews the procedures strictly against the IMO guidelines which AMSA enforces in Australia through Marine Order 34 and, if satisfied, issues the approval. This is the "Approval Certificate for the procedures for sampling, testing and controlling the moisture content" referenced on the AMSA 268 shipper's declaration. Importantly, this approval covers your procedures, not an individual cargo. The review takes time and should be initiated well before a loading window (e.g., 3-4 weeks for processing), not at the last minute.
The approval is valid for five years from the date of issue, with a mandatory initial verification endorsement required within twelve months of the original approval certificate's issuance. For this endorsement the shipper must contact their local AMSA office directly (with adequate time prior to the due date). This check is conducted by the local AMSA office and verifies that the approved procedures are actually being followed in practice. Note that without this endorsement, the approval will be invalidated and a new application will need to be made.
Step two: certification of each shipment
Separately from the Approval, for every cargo shipment, the shipper follows the approved procedures to produce a certificate/declaration of moisture content demonstrating that the actual moisture at the time of shipment is below the certified TML. These are provided to the Master before loading as part of the documentation supporting the Shipper’s Declaration. This certification is time-limited: the moisture content certificate must be issued within 7 days of loading, with re-testing required if there has been significant precipitation in the interim. The TML must be conducted within six months of loading. Regardless of this provision, the shipper must re-test the TML whenever a variation in the cargo's composition or characteristics is suspected.
Furthermore, you must apply to AMSA via the email address above for re-approval if:
You need to make changes to an MMP that has already been approved.
Your current Certificate of Approval is due to expire.
A period of 3 to 4 weeks should be allowed for processing.
To ensure you’re loading your Group A cargo compliantly, you need both steps in place:
Is the procedure approval current (and has it been verified within a year of issue)? and,
Is the shipment certification for the cargo completed within the required timelines prior to shipping?
The Group A list keeps evolving
The cargoes designated Group A are regularly updated. Recent editions of the Code have refined schedules for cargoes; for example the latest 08-25 Amendment (mandatory from Jan 1 2027) introduced a dedicated Group A schedule for PHOSPHATE ROCK FINES (uncalcined); a reminder that a material's classification can change with its particle size and processing, and that shippers need to keep pace with the current Code.
Davoren Environmental has significant experience in assisting clients in preparing their Moisture Management Plans in accordance with IMO guidelines for shipment approval. Contact us for advice or support in preparing an MMP info@davorenenvironmental.com.au.