Question 1

RISQ Q8.2-8.3 (Solid Bulk Cargo) requires the IMSBC Code's Group A/B/C cargo classification, and a signed certificate of moisture content, Transportable Moisture Limit (TML), and density before loading any cargo that may liquefy. Why is the comparison between actual moisture content and TML the single most safety-critical figure in this whole certificate?

Accepted Answer

A Group A cargo loaded with moisture content above its TML can liquefy under the ship's motion at sea — the cargo effectively becomes a fluid that can shift suddenly to one side, and this shift has caused real bulk carrier capsizes; everything else on the certificate (density, general description) supports planning, but moisture-vs-TML is the line between safe and potentially fatal Liquefaction is a well-documented cause of real bulk carrier losses with crew fatalities — a cargo that looks dry and granular at loading can still contain enough trapped moisture to liquefy once compacted by the ship's motion. This is exactly why RISQ treats the TML certificate as a hard gate (cargo must not be accepted if actual moisture exceeds TML), not as routine paperwork.

Question 2

RISQ's guidance describes the "can test" — half-filling a small container with cargo sample, striking it sharply on a hard surface 25 times, and checking for free moisture — as a method the Master can use at the dockside. What is the correct interpretation of a "dry" result from this test?

Accepted Answer

A dry-appearing result is a useful indicator but does NOT prove the moisture content is below the TML — RISQ's own guidance explicitly warns that material can still exceed the TML even if it remains dry-looking after the can test, so a clear can test is not a substitute for proper laboratory moisture testing This is a deliberately-included trap in the inspection guidance itself: the can test is a useful field check available to anyone onboard, but its limitation is explicit and important — passing it does not guarantee the cargo is actually below TML. Treating a dry can test as definitive proof of safety, rather than as one input alongside the shipper's certificate, is exactly the kind of overconfidence that has contributed to real liquefaction incidents.

Question 3

RISQ Q8.7 requires that "if a significant deviation from the agreed loading/unloading plan is detected, all cargo and ballast operations must STOP," with synchronisation between cargo loading rate and ballast pumping capacity specifically flagged as a risk area. Why can a mismatch between loading rate and ballast pumping capacity become dangerous, rather than just inefficient?

Accepted Answer

If cargo is loaded faster than the ballast system can de-ballast to compensate, the still-water shear forces and bending moments on the hull can exceed the vessel's designed limits before the loading plan's calculated checkpoints catch up — this is a real structural overstress risk, not merely a scheduling inconvenience The loading plan's calculated shear force and bending moment values assume cargo and ballast operations proceed roughly together as planned. High-rate terminal loaders can outpace a vessel's ballast pumps, meaning the actual hull stress at a given moment can exceed what the plan assumed at that same loading stage — which is precisely why RISQ requires operations to stop the instant a significant deviation is detected, rather than waiting to "catch up" later.