Question 1

RISQ Q8.18 requires coal-carrying vessels to be equipped with instruments measuring methane, oxygen, carbon monoxide concentrations, cargo temperature, and bilge sample pH — without requiring entry into the cargo space to take readings. The guidance specifically warns that probe thermometers measure only "up to 1m below the surface" and that sounding-pipe readings "will not provide information on the bulk of the cargo." What is the practical risk of relying solely on these surface/near-surface readings for a self-heating coal cargo?

Accepted Answer

Self-heating in coal typically originates within the bulk of the stow, not at the surface — a surface or near-surface reading can appear normal for some time while a genuine self-heating event develops deeper in the cargo, meaning the available instrumentation has a real, acknowledged blind spot that crew must understand rather than treat the readings as a complete picture This question tests genuine understanding of an instrumentation limitation that RISQ's own guidance flags explicitly, rather than just knowing that "instruments are required." A crew that understands probes only reach ~1m and sounding pipes only detect heating near the pipe itself is better placed to interpret a "normal" reading correctly — as reassuring but not conclusive — than a crew that assumes the instruments give full visibility into the cargo.

Question 2

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 3

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.