Question 1

The framework specifically flags "lack of spinning reserve" as "a potential hidden failure" in the context of hybrid power systems used to provide spinning reserve "more efficiently" than traditional rotating generation. Why is a missing or degraded spinning reserve specifically classified as a hidden failure, rather than a fault that would be immediately obvious?

Accepted Answer

Spinning reserve is a protective capacity that is only actually tested by the demand it is meant to cover — under normal, non-emergency power demand, a system with degraded or absent spinning reserve can appear to be functioning completely normally, with the gap only becoming apparent at the exact moment of a real power demand spike or generator loss, which is precisely the definition of a hidden failure: not evident to operations/maintenance personnel under normal conditions This is exactly the hidden-failure definition the framework establishes elsewhere — "not immediately evident to operations and maintenance personnel" — applied to a concrete, real example. A protective margin that is only tested by the emergency it is meant to cover is a textbook hidden failure risk, which is why the framework calls for continuous/periodic detection capability for state of charge and state of health on battery hybrid systems specifically to close this gap.

Question 2

OCIMF's DP FMEA Assurance Framework states it was developed because, despite extensive existing guidance, "a significant number of FMEAs lack comprehensive analysis," and that adherence to its prescribed format "will be confirmed by OVID inspectors as part of the DP FMEA assurance processes commissioned by OCIMF members." What does this tell a DP crew member about what an OVID inspection is actually checking when it comes to the FMEA?

Accepted Answer

The OVID inspector is not just confirming a class-approved FMEA document exists onboard, but assessing whether that document meets a specific quality and completeness standard (clear identification of common points, fail-safe conclusions, compensating provisions) — a vessel can hold a class-stamped FMEA and still fail this assurance check if the document itself is not comprehensive This is the critical, easily-missed point: OCIMF built this framework specifically because class approval alone was not catching FMEA quality gaps — the 2004 UK HSE/DNV review found weaknesses including non-thorough class review and late submission. An OVID inspection using this framework is checking the substance of the document, not just its existence or its class stamp.

Question 3

The framework defines a "common point" as an element that "interfaces with or influences redundant groups and... can defeat the redundancy concept," and states common points "cannot be eliminated completely in a redundant DP system" — closed bus ties, cross-connected control power supplies, and some hybrid power designs are cited as examples. Why does the framework treat common points as something to be managed rather than something a well-designed DP system simply avoids entirely?

Accepted Answer

Some common points exist because they are required to achieve specific legitimate design objectives (e.g. closed bus tie operation for certain power management benefits) — the framework's actual requirement is that any common point that does exist must be explicitly identified, its failure modes analysed, and its compensating provisions proven by testing, not that DP systems must have zero common points to be acceptable This is a precise, easily misunderstood point — the framework is not a zero-common-points standard, it is a "if a common point exists, prove you understand and have mitigated it" standard. A DPO or vetting-facing officer who assumes any common point automatically means a failed system, or conversely assumes common points are harmless because they sometimes serve a legitimate purpose, has both gotten the principle wrong in different directions.