Section 4.4 Testing Procedures and Certificates of Analysis

The safe carriage of many solid bulk cargoes, particularly those in Group A and Group B, hinges on accurate knowledge of their specific physical and chemical properties at the time of loading. This knowledge is not based on assumption or visual appearance alone but must be derived from standardized testing procedures conducted by competent entities. The results of these tests are formally documented in Certificates of Test or Certificates of Analysis, which are then provided to the Master by the shipper as an integral part of the cargo information. Understanding these testing procedures, the information contained in the certificates, and the Master’s role in scrutinizing them is crucial for preventing serious incidents.

1. The Purpose and Criticality of Testing:

Testing provides objective, quantifiable data about cargo properties that are directly linked to safety. For example:

  1. For Group A Cargoes (which may liquefy): Testing determines the Transportable Moisture Limit (TML) and the actual Moisture Content (MC) of the cargo. The relationship between these two values is the single most important factor in assessing the risk of liquefaction.
  2. For Group B Cargoes (chemically hazardous): Testing can identify:
    1. Propensity for self-heating and spontaneous combustion (e.g., for coal, DRI).
    2. Rate of flammable or toxic gas emission.
    3. Presence of hazardous impurities.
    4. Other chemical characteristics relevant to safe carriage (e.g., pH, reactivity).

Without reliable test results, the Master would be operating in the dark, unable to make informed decisions about whether a cargo is safe to load or what precautions are necessary during the voyage.

2. Key Testing Procedures Mandated or Referenced by the IMSBC Code:

The IMSBC Code, particularly in its appendices and individual cargo schedules, specifies or refers to various testing procedures.

  1. A. Tests for Group A Cargoes (Liquefaction Risk Assessment): Appendix 2 of the IMSBC Code details the approved test procedures for determining the TML of mineral concentrates and other cargoes that may liquefy. The shipper is responsible for ensuring these tests are conducted. The three primary methods are:
    1. 1. Flow Table Test (Section 1 of Appendix 2):
      1. Principle: This test determines the “flow moisture point” (FMP), which is the percentage moisture content at which a sample of the cargo begins to deform and flow like a liquid when subjected to vibration or impact on a standardized flow table. The TML is then set at 90% of the FMP (TML = 0.9 x FMP).
      2. Procedure: A representative sample of the cargo is placed in a mould on the flow table. The table is then raised and dropped a specific number of times (typically 25 times in 15 seconds). This is repeated with samples at varying moisture contents until the flow moisture point is identified.
      3. Applicability: Generally suitable for fine-grained materials with a significant portion of particles less than 1 mm, and a smaller portion of larger particles (up to 7 mm).
    2. 2. Penetration Test (Section 2 of Appendix 2):
      1. Principle: This test also determines the FMP by observing the depth to which a standardized penetration bit sinks into a sample of cargo when subjected to impact. The TML is 90% of the FMP.
      2. Procedure: A representative sample is placed in a cylindrical container. A weighted penetration bit is dropped onto the surface of the sample from a fixed height. If the penetration exceeds 50 mm, the sample is considered to have reached its flow state at that moisture content. This is repeated with samples at varying moisture contents.
      3. Applicability: Suitable for granular materials with a predominant particle size up to 25 mm and where the flow table test is not appropriate (e.g., coarser materials).
    3. 3. Proctor/Fagerberg Test (Section 3 of Appendix 2):
      1. Principle: This is a more complex laboratory test used to determine the TML for fine-grained and relatively coarse-grained materials (up to 50 mm particle size) where the other methods might not be suitable, particularly for coal. It involves compacting the material at various moisture contents to determine its optimum moisture content (OMC) and the degree of saturation at which a flow state can occur. The TML is derived from these parameters.
      2. Procedure: Involves compacting samples in a standard Proctor mould using a specific compactive effort, determining moisture content, dry density, and then calculating void ratios and saturation levels. A specific procedure (Procedure D in the Code) is used for coal.
      3. Applicability: Can be used for a wider range of materials, including coal up to 50 mm. It is often considered more reliable for certain “cohesive” materials.
    4. Moisture Content (MC) Determination (Section 4 of Appendix 2):
      1. Principle: The actual moisture content of the cargo to be loaded must be determined from representative samples.
      2. Procedure: Typically involves weighing a sample, drying it in an oven at a specified temperature (usually 105°C) until constant weight is achieved, and then re-weighing. The difference in weight represents the moisture lost. The moisture content is expressed as a percentage of the total wet weight of the sample.
      3. Sampling: This is a critical aspect. Samples taken for MC determination must be truly representative of the entire consignment to be loaded. The IMSBC Code provides guidance on sampling procedures. Poor sampling can lead to dangerously misleading MC results.
  2. B. Tests for Group B Cargoes (Chemical Hazards): The specific tests depend on the nature of the cargo and its potential hazards as outlined in the individual IMSBC Code schedule. Examples include:
    1. Self-Heating Tests (e.g., for Coal, DRI): Various tests (e.g., adiabatic tests, basket heating tests, crossing point temperature tests) can be used to assess a cargo’s propensity to self-heat and the rate of heat generation. The results help determine safe stowage periods, ventilation requirements, and whether the cargo needs weathering.
    2. Gas Evolution Tests (e.g., for Coal – Methane; DRI – Hydrogen): Tests to determine the rate at which flammable or toxic gases are emitted under specific conditions.
    3. Reactivity Tests: To assess how a cargo might react with water, air, or other substances.
    4. Flashpoint Tests: For materials that might give off flammable vapors.
    5. Chemical Analysis: To determine the concentration of hazardous components or impurities.
    6. UN N.4 Test (Trough Test for Readily Combustible Solids): For some cargoes, to determine if they are “readily combustible.”
    7. Tests for Self-Sustaining Decomposition (e.g., for Ammonium Nitrate Based Fertilizers).

3. Certificates of Test / Certificates of Analysis:

These are formal documents, provided by the shipper, that attest to the properties of the cargo as determined by the prescribed testing procedures.

  1. Essential Information on Certificates:
    1. Clear identification of the cargo (BCSN, and any other relevant identifiers).
    2. Name and address of the testing laboratory or competent entity that performed the tests.
    3. Date of sampling and date of testing (crucial for timeliness).
    4. The specific test method(s) used (e.g., “Flow Table Test as per IMSBC Code Appendix 2, Section 1”).
    5. The results of the tests:
      1. For Group A: Clearly stated TML and MC values.
      2. For Group B: Clearly stated results relevant to the hazards (e.g., self-heating rate, gas evolution data, chemical composition).
    6. A statement that the tests were conducted in accordance with the relevant standards or IMSBC Code procedures.
    7. Signature of a responsible person from the testing entity.
    8. Identification of the consignment/stockpile from which the samples were taken.
  2. Issuing Authority/Competent Entity:
    1. Tests should be conducted, and certificates issued, by a laboratory or entity that is properly equipped, has qualified personnel, and is recognized as competent by the relevant authority of the port of loading (e.g., a government agency, an accredited independent laboratory, or a testing facility approved by the competent authority). The shipper is responsible for selecting such an entity.
  3. Timeliness and Validity:
    1. Crucial for MC and TML: As moisture content can change due to weather or stockpile conditions, the IMSBC Code stresses that testing for MC (and sometimes TML if conditions change significantly) should be conducted “as near as practicable to the time of loading.”
    2. IMSBC Code Guidance (Section 4.5):
      1. The interval between sampling/testing and loading for MC & TML should not exceed 7 days.
      2. If there has been significant rain or snow on the cargo between testing and loading, the shipper must advise the Master, and re-testing of MC may be necessary. The Master has the right to request this.
    3. For other properties (e.g., some chemical characteristics), the “validity” might be longer if the property is stable, but this should be assessed based on the cargo type.

4. The Master’s Role and Responsibilities:

The Master’s role is not just to receive these certificates but to critically evaluate them.

  1. Scrutiny of Certificates:
    1. Check for completeness of information (as listed above).
    2. Verify the issuing authority appears legitimate and competent.
    3. Pay close attention to dates of sampling and testing. Are they recent enough?
    4. For Group A, perform the critical comparison: Is MC < TML? If not, or if very close, exercise extreme caution and seek further advice/re-testing.
    5. Ensure the test methods cited are those prescribed by the IMSBC Code.
    6. Look for any qualifications, disclaimers, or unusual remarks on the certificate.
  2. Understanding Limitations:
    1. Recognize that a certificate reflects the condition of the sample tested. The Master must consider whether the sample was truly representative of the entire cargo consignment to be loaded. If loading from multiple stockpiles or if there’s visible variation in the cargo, this is a concern.
    2. Be aware that cargo conditions can change after testing (e.g., due to rain on an uncovered stockpile).
  3. Actions if Certificates are Suspect or Cargo Condition Changes:
    1. If the Master has any doubt about the validity of a certificate, the accuracy of the results, the representativeness of the samples, or if the cargo’s physical appearance (e.g., excessive wetness) contradicts the certificate, they must raise these concerns with the shipper and the company.
    2. The Master has the authority to request re-sampling and re-testing before loading. P&I Clubs often support Masters in such situations if concerns are well-founded.
    3. Refuse to load if satisfactory clarification or new, valid certificates demonstrating safety are not provided.
  4. The “Can Test” (IMSBC Code, Section 8.4) – A Supplementary Shipboard Check:
    1. Purpose: This is a simple, indicative shipboard test that can be performed by the crew on a representative sample of a Group A cargo if there are doubts about its moisture condition (e.g., if it appears wetter than certified, or if no certificate is available for a cargo that might be Group A).
    2. Procedure: A small can (0.5 to 1 litre) is half-filled with a representative sample of the cargo. The can is then banged hard on a firm surface (e.g., deck) for a minute or two (e.g., 25 times).
    3. Indication: If free moisture or a “soupy” liquid appears on the surface of the sample after banging, it indicates that the cargo may be unsafe due to high moisture content (i.e., it may be at or above its flow moisture point).
    4. Limitations:
      1. The Can Test is not a substitute for proper laboratory testing and certification of TML and MC.
      2. A “pass” on the Can Test (no free moisture) does not definitively mean the cargo is safe if the certified MC is already above or very close to the TML.
      3. A “fail” on the Can Test (free moisture appears) is a strong indicator that the cargo may be unsafe, and loading should be stopped pending further investigation, laboratory re-testing, and expert advice.
    5. The Master should use the Can Test as an additional precautionary check, especially if there are visual concerns or discrepancies with documentation.

In summary, testing procedures and the resultant Certificates of Analysis are the scientific backbone supporting the safe carriage of many solid bulk cargoes. They provide the objective data needed to make critical safety decisions. The Master’s role in diligently reviewing these certificates, understanding their implications, and being prepared to challenge them, if necessary, is a cornerstone of responsible seamanship and a key defense against the inherent hazards of the bulk trade.

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