What is the flow table test, and how is bulk cargo liquefaction controlled?

flowchart LR
  A["Group A cargo: may liquefy (IMSBC section 7)"] --> B["Laboratory test on a representative sample: flow table, penetration or Proctor-Fagerberg (appendix 2)"]
  B --> C["Flow moisture point (FMP)"]
  C --> D["TML = 90% of the FMP"]
  D --> E{"Actual moisture content below the TML (section 8)?"}
  E -->|Yes| F["Load; watch for liquefaction on passage"]
  E -->|No, or the can test shows free moisture| G["Do not load until proven safe"]

• Hazard: a Group A cargo above its transportable moisture limit can liquefy under vibration and rolling, shift and capsize the ship (IMSBC section 7).
• Two limits: the flow moisture point (FMP), where flow first develops under test; TML = 90% of the FMP; load only with the actual moisture below the TML (section 8, shipper’s certificate under SOLAS VI/2).
• Tests (appendix 2): the flow table test (FTT), the sample in a mould tapped on a flow table until the cone deforms, for fine concentrates; the penetration test; the modified Proctor-Fagerberg test for iron ore fines and coal.
• Can test (8.4): a can half-filled and tapped about 25 times; free moisture means laboratory tests before loading; a screening test, not a substitute.
• Rule: certificate sampled close to loading; after rain or a positive can test, stop and re-test; watch for liquefaction on passage.
• As Chief Engineer: the ballast and stability margin assume the cargo stays solid; if liquefaction is indicated, loading stops.