Learning
Mistake Library
The archive of the most common mistakes, with the typical consequence and a link to the page explaining how to avoid them.
Educational use. This view supports study, familiarisation and preparation. It does not certify competence or compliance and does not replace the SMS, approved procedures or documents, authority decisions, or verification of current sources. If content differs, the linked topic governs.
| Topic | Mistake | Typical consequence | Page |
|---|---|---|---|
| PSC documentary preparation — passenger / ro-ro ship | Using Annex IV as an identical list for every ship | Confuses inclusion in the Annex with applicability to the ship | View page → |
| TMSA: the Company's self-assessment, not the ship's | Level declared from a procedure alone, without cumulative criteria and operational evidence | Maturity overstated against implementation | View page → |
| CDI-M: the Ship Inspection Report for chemical tankers, gas carriers and beyond | Wrong inspection type | Irrelevant scope | View page → |
| IOPP Certificate: the Supplement is the document that matters | Checking only expiry, using an outdated supplement or assuming a domestic ship is outside MARPOL. | Check the individual ship’s requirements and documents before closing the work. | View page → |
| Oil Record Book — Part I (Machinery Space Operations) | Operation not signed by the officer in charge, or completed page not signed by the Master | PSC deficiency, possible detention | View page → |
| Sludge Management | Sludge balance with a large, unexplained variance | Suspicion of illegal discharge, in-depth investigation | View page → |
| Bilge Water | Avoid confusing testing with calibration, inferring stopping from tonnage, treating 15 ppm as geographical permission, or omitting applicable ORB fields. Check area, equipment, certificates and records. | See the linked page for conditions, consequences and preventive measures. | View page → |
| Garbage Record Book | Avoid confusing the plan with the record book, extending the international-voyage qualification to all ships, recording retained garbage as delivered, omitting incineration or losses, or invoking an exception without documenting its conditions and precautions. | See the linked page for conditions, consequences and preventive measures. | View page → |
| Incinerator | Avoid banning PVC without considering appropriate approval, accepting sludge from other ships, replacing continuous monitoring with hourly readings, or confusing generated ashes with delivered ashes. There is no universal ratio between running hours and ash quantity. | See the linked page for conditions, consequences and preventive measures. | View page → |
| Ballast Water | Avoid unilateral D-1 after failure, preventive bypass based on a previous port difficulty, postponing plan/familiarization until future amendments, confusing BWMS approval with the IBWMC, or omitting final position A.2. | See the linked page for conditions, consequences and preventive measures. | View page → |
| Fuel Changeover | Avoid calculating one pipe instead of the system, omitting compatibility/viscosity checks, completing after the boundary, missing tank volumes, treating FONAR as permission, or converting two geographical transitions into two necessarily mandatory fuel changes. | See the linked page for conditions, consequences and preventive measures. | View page → |
| MARPOL Annex VI | Avoid omitting the ODS equipment list/Record Book and Regulation 12.6 entries; avoid prohibiting HSFO without checking equivalence, treating every old engine as Tier II, omitting 13.5.3 records, confusing EIAPP with the IAPP calendar, applying CII to every DCS ship, or merging SOx and NOx dates. | See the linked page for conditions, consequences and preventive measures. | View page → |
| Managing a Non-Conformity (NC) | NC closed without verifying the effectiveness of the action | The root cause remains and the NC recurs (repeat NC) | View page → |
| Reporting a Near Miss | Punitive culture towards those who report | The reporting rate collapses and useful information is lost | View page → |
| Fire Drill and Fire Safety | Drill conducted as a simple announcement, without practical use of the equipment | The crew does not gain real familiarity with emergency procedures | View page → |
| ECDIS (Electronic Chart Display and Information System) | ENCs not updated or subscription expired | Navigation with outdated chart data, PSC deficiency | View page → |
| Crew Familiarisation and Training | Signature without checking understanding | Nominal preparation only | View page → |
| Musters and Abandon Ship Drill | Emergency duties not understood before sailing or onboard training later than two weeks | PSC deficiency, real risk in the event of an emergency before familiarization is completed | View page → |
| Managing Deficiencies | Deficiency rectified but not linked to the SMS's NC/CAPA system | The root cause is not analysed and the deficiency recurs at subsequent inspections | View page → |
| Communicating with the PSCO | Rehearsed, uniform answers from the whole crew, perceived as not genuine | The PSCO extends the inspection to verify the substance behind the answers | View page → |
| Enclosed Space Entry | Entry without instrumental verification of the atmosphere, relying only on the visual appearance of the space | An oxygen-deficient or toxic atmosphere goes undetected, a mortal risk | View page → |
| COLREG in Practice | Writing Every ship under way as the general scope, confusing heading and track under Rule 10, or describing MASS as still expected in May 2026. | Incorrect operational decision or regulatory status | View page → |
| Bridge Resource Management (BRM) | Tasks not explicitly assigned during critical phases, with overlaps or gaps in responsibility | No one monitors a critical aspect, assuming someone else is handling it | View page → |
| Planned Maintenance System (PMS) and Auxiliary Machinery | Automatically deriving an interval or minimum inventory from critical classification alone. | Non-compliant decision or treatment | View page → |
| Tail Shaft Survey | Presenting Continuous Machinery Survey/CMS as an autonomous choice to avoid shaft withdrawal or using one five-year cycle. | Non-compliant decision or treatment | View page → |
| Intermediate Survey | Scheduling IOPP in month 30 as though the windows were continuous, or deferring every defect to the next survey without assessing severity and the assigned deadline. | Check the individual ship’s requirements and documents before closing the work. | View page → |
| EEXI and Engine Power Limitation (EPL) | Using the power reserve to recover commercial delays. | Use outside the safety purposes provided for override. | View page → |
| Sewage Management | Avoid “at least 12” instead of “more than 12”, measuring from a generic coast rather than MARPOL nearest land, treating the approved rate as optional, or using an STP as permission in every jurisdiction. | See the linked page for conditions, consequences and preventive measures. | View page → |
| Bunker Delivery Note | Avoid sampling LNG as conventional fuel, copying the BDN onto the label, making representatives optional, discarding at month twelve without checking consumption, or opening the statutory sample for an ordinary commercial claim. | See the linked page for conditions, consequences and preventive measures. | View page → |
| Handling Seafarer Complaints (MLC 2006) | Complaint procedure not provided or not clearly explained to the seafarer on joining | Seafarer unaware of their rights and the complaint procedure, MLC deficiency at inspection | View page → |
| Permit to Work System | Hot work permit renewed without a new atmosphere test if the work extends beyond the initial validity | Risk conditions not updated, possible accident with an atmosphere that has changed in the meantime | View page → |
| Ship Security Plan and the ISPS Code | SSO lacks a VI/5 CoP valid under Administration and flag rules | Clear ground for a more detailed security examination | View page → |
| Life-Saving Appliances: Liferafts, EPIRB and SART | Applicable liferaft servicing interval exceeded | Serious deficiency, possible detention | View page → |
| USCG Port State Control | Confusing an eligible flag with a QUALSHIP 21-enrolled vessel | Incentives or boarding expectations are applied when unavailable | View page → |
| Tokyo MOU: Regional Specificities | Applying Paris MoU profiles and priorities in Tokyo MoU | Preparation is not calibrated to the competent regime | View page → |
| Ro-Ro Cargo Securing | Crew calculates an out-of-CSM configuration ad hoc | Arrangement lacks the required approved basis | View page → |
| Reefer Container Monitoring | Confusing set point, air temperature and product temperature: record which quantity is measured. | See the linked page for conditions, consequences and preventive measures. | View page → |
| Managing Cargo Claims | Unqualified bill despite apparent defects | It may be prima facie evidence of receipt as described and materially restrict contrary evidence, especially against a lawful third-party holder | View page → |
| Passage Planning in Polar Waters (Polar Code) | Applying one date to every added ship | Requirement applied early or deadline missed | View page → |
| Electronic Navigation and GNSS Resilience | Promising accurate position with L1/L2/L5 during complete interference or making multi-band/RAIM universally mandatory. | Incorrect operational decision or regulatory status | View page → |
| VTS Traffic Management | Treating every VTS message as a binding order or, conversely, reducing every instruction to a mere recommendation. | Incorrect operational decision or regulatory status | View page → |
| Boiler Operations | Always ordering a safety-valve test under actual working conditions or confusing crew inspection with statutory internal inspection. | Non-compliant decision or treatment | View page → |
| Refrigeration Plant | Extending the full F-gas regime to every ship or saying high-GWP was simply banned in 2020 without thresholds, transition and reclaimed/recycled exceptions through 2030. | Non-compliant decision or treatment | View page → |
| Operational Energy Efficiency in the Engine Room | Main engine run chronically at very low loads for commercial reasons, without monitoring the impact on specific efficiency | Specific consumption worse than expected, with a negative impact on the CII rating | View page → |
| Anchor and Chain Cable Survey | Declaring full five-year gauging and measuring every link at every Renewal/Special Survey. | Non-compliant decision or treatment | View page → |
| Cargo Hold Survey for Bulk Carriers (ESP) | Attributing drone/coating/survey extent to UR Z11, saying formally recognized since 2025, or using generic age thresholds as ESP entry trigger. | Non-compliant decision or treatment | View page → |
| Shipyard Waste Management during Dry Dock | Classification by name | Wrong code and destination | View page → |
| Safety Construction, Equipment and Radio Certificate | Always expecting three separate documents or using the Radio date as proof that other scopes were also examined. | Check the individual ship’s requirements and documents before closing the work. | View page → |
| ISPS Certification (International Ship Security Certificate) | Confusing expiry with the intermediate window, or treating detention as automatic for every ISSC problem. | Check the individual ship’s requirements and documents before closing the work. | View page → |
| MLC Certification (Maritime Labour Certificate and DMLC) | Updating the DMLC without handling certification; calculating anniversaries from issue; postponing existing duties until 2027. | Check the individual ship’s requirements and documents before closing the work. | View page → |
| Ballast Water Management Convention In Depth | Using type approval as the only evidence of onboard commissioning. | Evidence of correct installation and testing on the ship is missing. | View page → |
| Biofouling Management | Requiring a certified in-water cleaning service or claiming formal IMO compliance without an identified scheme. | Non-compliant decision or treatment | View page → |
| Underwater Radiated Noise (URN) | Writing EBP until 2026, possible extension, or turning the extension into a mandatory obligation. | Non-compliant decision or treatment | View page → |
| Anti-Fouling Systems | Avoid equating “no dry-docking since 2023” with an exception for an ordinary ship, confusing documentary thresholds with freedom of use, renewing a system with only an internal entry, or treating flag notification as an automatic extension. | See the linked page for conditions, consequences and preventive measures. | View page → |
| VOC Management Plan | Avoid a generic plan without COW or a responsible person, language unsuitable for the voyage, confusing VECS with the whole plan, treating three-year acceptance as a right, or turning the P/V proposal into an instruction to modify equipment. | See the linked page for conditions, consequences and preventive measures. | View page → |
| Management of Change (MoC) | Internal approval without checking statutory limits | Inadmissible activity despite a MoC | View page → |
| Dangerous Goods Manifest and Notification to Port Authorities | Manifest compiled on the basis of initial declarations without being updated after changes to the stowage plan | Incorrect information on the actual position of the dangerous goods in an emergency | View page → |
| Lithium Batteries: Thermal Runaway and Fire Response on Board | Universal agent/strategy | Response conflicts with stowage or ship | View page → |
| IMDG Training and Crew Education | Shore-based Chapter 1.3 training and shipboard competence requirements not distinguished | The wrong legal basis and training path are assigned to personnel | View page → |
| Watertight Doors and Compartment Integrity | Door category and applicable rule not identified before setting its position at sea | A passenger-ship or category-specific provision is generalised to the wrong ship or door | View page → |
| Helicopter Operations and Helideck Safety | Helicopter operation conducted without dedicated firefighting personnel present during refuelling | Critical response time lost in the event of ignition during refuelling | View page → |
| Black Sea MOU: Regional Specificities | Using the 2025 rate as proof of stricter inspection | A descriptive figure is converted into a cause | View page → |
| Indian Ocean MOU: Regional Specificities | Transferring another MoU’s profiles or priorities to IOMOU | Preparation is not calibrated to the competent Authority | View page → |
| Heavy Lift Cargo and Project Cargo | Improvised onboard Annex 13 calculation | Structural assessment and acceptance process are missing | View page → |
| BNWAS and Anti-Collision Alert Systems | Presenting under way and autopilot as alternative triggers or inventing a uniform IMO periodicity for end-to-end/power-failure tests. | Incorrect operational decision or regulatory status | View page → |
| Predictive Maintenance based on IoT Sensors | Citing 70% of new ships, 2024/2034 market values, or presenting predictive maintenance as automatic replacement. | Non-compliant decision or treatment | View page → |
| Boiler Water Treatment | Imposing six daily tests, declaring polyelectrolyte superior, using 1,000 µS/cm, 15 minutes/watch or universal numerical dosing. | Non-compliant decision or treatment | View page → |
| Managing Shipyard Repair Contracts | Timeline presented as a standard | False assurance | View page → |
| Managing Surveys under Dual/Multiple Classification | Confusing double and dual class; using only one status; assuming all work is automatically accepted. | Check the individual ship’s requirements and documents before closing the work. | View page → |
| Statement of Compliance for Ships in Temporary Lay-up | Document treated as universal | Legal effect overstated | View page → |
| Digitalization of Statutory Certificates | Citing only FAL.5/Circ.39/Rev.2 as current or calling MLC an IMO Convention. | Non-compliant decision or treatment | View page → |
| Onboard Carbon Capture and Storage (OCCS) | Calling OCCS a lower-intensity energy source or promising settled future accounting. | Non-compliant decision or treatment | View page → |
| Shore Power and Cold Ironing (Onshore Power Supply) | Conflating AFIR and FuelEU | Separate infrastructure duties, ship duties and availability at the individual quay. | View page → |
| Wind-Assisted Propulsion Systems (WAPS) | Saving transferred from another ship | Unreliable business case | View page → |
| Dangerous Solid Bulk Cargoes: the IMSBC Code, Liquefaction and Self-Heating | Doubt about the shipper's moisture-content certificate treated as resolved by a shipboard indication | Cargo with moisture above the TML loaded without the risk being detected | View page → |
| MARPOL Annex III: Harmful Substances Carried in Packaged Form | 'MARINE POLLUTANT' marking not applied because it is considered redundant relative to the primary IMDG class labelling | Non-compliance with MARPOL Annex III even when the IMDG safety classification is correct | View page → |
| Polar Waters Discharges | Avoid measuring from ice instead of also from land, equating STP certification with discharge approval, carrying an HFO waiver into another Party’s waters, or treating low-sulphur fuel as automatically outside the HFO definition. | See the linked page for conditions, consequences and preventive measures. | View page → |
| Contractor and External Supplier Management | Supplier controls inadequate for the service or SMS | Competence, approvals or safety not demonstrated; possible NC | View page → |
| Whistleblowing and Anonymous Reporting of Non-Conformities | Anonymity and confidentiality treated as synonyms or universal MLC duties | Incorrect expectations and legal basis | View page → |
| Immersion Suits and Thermal Protection | Immersion suits counted from the number of lifeboats on a cargo ship, where the criterion is per person | Fewer suits than persons embarked, with the shortfall never showing up in any count | View page → |
| Fixed Firefighting Systems: CO2 and Water Mist | CO2 system dosing not re-verified after structural modifications to the protected space | Insufficient CO2 concentration for effective extinguishing in the modified space | View page → |
| Means of Escape and Emergency Escape Routes | Means of escape from Category A machinery spaces verified only for their formal existence, without verifying the actual independence of the two routes | Both means of escape potentially compromised by the same event (e.g. a fire blocking a single common route) | View page → |
| Managing an Appeal against a Detention | Appeal addressed to the individual PSCO who carried out the detention instead of the competent maritime authority of the port State | Appeal not processed according to the correct formal procedure | View page → |
| Coordination between Flag State and PSC | Saying A.1206(34) introduced the DAO | The function’s origin and powers are assigned to the wrong source | View page → |
| Break Bulk Cargo: Stowage, Dunnage and Damage Prevention | Stowage planning without reliable and verified weight, dimensions and centre-of-gravity data for the items concerned | Cargo instability and risk of damage during transport | View page → |
| Charter Parties and Cargo-Specific Clauses | Voyage and time charter confused | Wrong economic mechanism | View page → |
| Icebreaker-Assisted Convoy Navigation | Saying convoy command replaces the Master's independent safety judgement or using seasonal statistics as an operational requirement. | Incorrect operational decision or regulatory status | View page → |
| Datum Shift and Chart Reference in ECDIS | Describing every datum uncertainty as GPS/ECDIS error, checking datum notes alone, or applying an unauthorised manual offset. | Incorrect operational decision or regulatory status | View page → |
| Integrated Automation Systems and Unmanned Machinery Space (UMS) | Imposing a daily full alarm/shutdown test or hard-coding a call to the Chief Engineer for every arrangement. | Non-compliant decision or treatment | View page → |
| Digital Twin for the Engine Room | Investment without checking the data needed for the use case | Simulation model fed by insufficient or low-quality data, with unreliable predictions | View page → |
| Managing Post-Repair Warranties (Warranty Claims) | Assumed duration | Wrong deadline | View page → |
| Dry Dock Scheduling for Sister Ships (Sister Ship Scheduling) | Specification copied | Scope over or understated | View page → |
| Interim Certificates | Treating interim certificate as one SOLAS/MARPOL/MLC mechanism or claiming the same compliance/value as definitive. | Non-compliant decision or treatment | View page → |
| Coordination between Class Surveys and Statutory Surveys (RO) | HSSC used for class | Wrong window | View page → |
| Methanol and Ammonia Bunkering: Infrastructure and Real Cases | Citing 48/200 ports, most ports or first ships 2026–2027 without primary source and method. | Non-compliant decision or treatment | View page → |
| Just Transition and the Social Impact of Decarbonization | Identical training for everyone | Gaps in critical roles | View page → |
| Review of the EU MRV Framework in Light of the EU ETS | Wrong COM number | Source concerns a different ETS measure | View page → |
| IMO DCS Transport Work | Incomplete period: recover, reconcile and submit gaps to the verifier, not delete the year. | See the linked page for conditions, consequences and preventive measures. | View page → |
| Prevention of Violence and Harassment Onboard | PSSR course delivered from 2026 without the new competence | Training does not meet the amended table | View page → |
| Master's Authority and Safety Culture | Master's overriding authority documented in the SMS but not concretely supported when the safety decision carries a commercial cost | Erosion of the Master's trust in the system and implicit pressure to favour commercial needs | View page → |
| Ro-Ro and Vehicle Spaces: New Fire Detection and Protection Requirements (2026) | Keel-laying date not verified to determine applicability of the new 2026 requirements | Detection system design not compliant with the requirements applicable to the ship | View page → |
| Shipboard Lifting Appliances: The New SOLAS Regulation II-1/3-13 Regime | Cargo cranes left out of the survey, on the view that Regulation II-1/3-13 covers only non-commercial appliances | In-scope appliances are omitted from controls, documentation and planning. | View page → |
| Mediterranean MOU: Regional Specificities | Calling the 20% rise in the 2024 detention count a rate increase | Count and rate are confused | View page → |
| Bulk Carriers: PSC Risk Profile and Recurring Deficiencies | Assigning the aggregated DNV ranking to bulk carriers alone | Operational priorities rely on a non-existent disaggregation | View page → |
| BLU Code: Safety in the Loading and Unloading of Bulk Carriers | Using the information exchange instead of the agreed plan and checklist. | See the linked page for conditions, consequences and preventive measures. | View page → |
| Mandatory Reporting of Containers Lost at Sea (SOLAS 2026) | Observation automatically sent to flag State as SOLAS duty | Recipients for the two events are confused | View page → |
| Cargo Record Book (Record Book for Noxious Liquid Substances) | Prewash not compliant with the P&A Manual | Annex II breach | View page → |
| Cargo Securing Manual and Cargo Lashing | Cargo Securing Manual not updated after changes to the securing equipment | The manual no longer reflects the ship's actual securing capacity | View page → |
| Draft Survey and Determining Cargo Quantity | Confusing the ship’s constant with variable ballast and consumables: measure the latter at initial and final surveys and check lightship and constant separately. | See the linked page for conditions, consequences and preventive measures. | View page → |
| IMDG Code — Carriage of Dangerous Goods in Packaged Form | Using 41-22 as a current alternative in 2026: verify the version applicable to the shipment. | See the linked page for conditions, consequences and preventive measures. | View page → |
| Loading/Discharging Plan | Ship/shore plan applied outside its scope | Wrong operating regime | View page → |
| Tank Cleaning | Using the P&A Manual as the sole safety guide or guarantee of next-cargo purity. | See the linked page for conditions, consequences and preventive measures. | View page → |
| Simulator Training: the Ongoing STCW Review | Presenting 37 States, three months and specific Regulations as a Committee outcome without the exact primary document and paragraph. | Incorrect operational decision or regulatory status | View page → |
| MASS Code: the New IMO Framework for Autonomous Ships | Saying entered into force, inventing a two-year voluntary introduction period, treating EBP as begun, or turning 2030/2032 into legal certainty. | Incorrect operational decision or regulatory status | View page → |
| Methanol Engines: Reliability and Spare Parts Management in a Still-Young Technology | Claiming 149 to 61 because of engine reliability problems or generalising supply-chain immaturity to every maker. | Non-compliant decision or treatment | View page → |
| Fire Safety of Onboard Battery Rooms (BESS) | Imposing massive and prolonged cooling, improvising isolation/water, entering before risk clearance, or treating EMSA/drills as universally mandatory. | Non-compliant decision or treatment | View page → |
| Hong Kong Convention: Inventory of Hazardous Materials and Green Passport | Confusing a Green Passport with a verified IHM, leaving the inventory unchanged since first issue, or applying the HKC 2030 deadline to EU documents already due. | Check the individual ship’s requirements and documents before closing the work. | View page → |
| Next-Generation Coating: Planning the Dry Dock Choice | Selecting on price or advertised life alone, ignoring niche areas, or confusing a product data sheet with the ship’s AFS certificate. | Check the individual ship’s requirements and documents before closing the work. | View page → |
| Hot Work Permit at the Shipyard: Ship-Dock Coordination | Using entry readings as hot-work authorisation, ignoring adjacent spaces or continuing after conditions change. | Check the individual ship’s requirements and documents before closing the work. | View page → |
| Change of Flag and the Shadow Fleet: What Changes for Surveys and Certificates | Saying issue before previous certificates expire as a general continuity guarantee. | Non-compliant decision or treatment | View page → |
| Coordination between the HSSC Cycle and SIRE 2.0 Vetting Inspections | Saying every crew member must answer the entire SIRE 2.0 Question Library. | Non-compliant decision or treatment | View page → |
| CII: 2027-2030 Reduction Factors and New SEEMP Granularity | Applying Z to the previous year’s result | Required CII is calculated from the wrong base | View page → |
| Alternative Fuels and Operational Readiness | Applying IGF Code compliance indiscriminately to ammonia, hydrogen, methanol and LPG. | Non-compliant decision or treatment | View page → |
| CII (Carbon Intensity Indicator) | Treating a single D as three consecutive D ratings | The corrective-action obligation is misstated | View page → |
| EU ETS and FuelEU Maritime | Writing all MRV ships enter ETS in 2027, one ≥5,000 scope, or 100% of every global emission. | Non-compliant decision or treatment | View page → |
| SEEMP Part II and Part III | Conflating Parts II and III | DCS methodology and CII planning are not checked against their respective scopes | View page → |
| Environmental Vetting and GHG Rating | Claiming automatic exclusion by BHP/Vale/Cargill/Rio Tinto or merging GHG, Safety Score and age trigger. | Non-compliant decision or treatment | View page → |
| Carriage of Radioactive Materials: IMDG Class 7 and the INF Code | Port-call and transit regimes treated as identical | Route requirements omitted or approvals sought without checking their basis | View page → |
| Dangerous Goods in Holds on Non-Containerised General Cargo Ships | Mode-specific stowage and segregation provisions not applied to conventional non-containerised cargo | Physically insufficient segregation distance in the hold | View page → |
| CTU Code: Packing and Stowage of Cargo Transport Units | CTU filled without a prior check of the structural integrity of the unit | Risk of loss of tightness or structural failure during transport | View page → |
| EmS Guide and MFAG: Responding to Emergencies Involving Dangerous Goods | EmS Guide or MFAG on board in an edition not consistent with the IMDG edition applied to the cargo | Absence of emergency procedures for the new entries introduced by the latest amendment | View page → |
| IBC Code and Operations on Chemical Tankers | P&A always attributed to class | Approval authority misstated | View page → |
| Liquefied Gases and Operational Notes on the IGC Code | Tank cooldown carried out too quickly relative to the prescribed cooling curve | Risk of thermal shock and structural damage to the containment system | View page → |
| Safe Return to Port: The Design Principle for Passenger Ships | Treating SRtP system redundancy as purely a design feature, without verifying its operational upkeep over time | Progressive degradation of the actual return-to-port capability compared with what was foreseen at the design stage | View page → |
| Passenger Musters at Embarkation: Before Departure, No Longer Within 24 Hours | Still applying, out of habit or outdated training, the old rule of a muster 'within 24 hours of departure' | Non-compliance with SOLAS III/19 as amended from 2015, with passengers lacking safety instructions for a stretch of the voyage | View page → |
| Damage Stability of Ro-Ro Passenger Ships (SOLAS 2020) | Determining the regime from keel date alone or from a sister ship’s date | A vessel caught by the delivery trigger or another SOLAS 2020 trigger may be classified incorrectly | View page → |
| Managing a Gastrointestinal Outbreak on Board | Waiting for a percentage threshold before applying the plan’s measures to an individual AGE case | Delayed identification, management and containment | View page → |
| SAR Cooperation Plan on Passenger Ships | SAR cooperation plan developed only once and never updated afterward | Plan no longer consistent with the actual operating area or the SAR services actually available | View page → |
| Persons with Reduced Mobility: Accessibility on Board | Extending the EAA indiscriminately to every digital system and onboard self-service terminal | The compliance perimeter exceeds the Directive’s scope | View page → |
| Evacuation Analysis on Passenger Ships: Simplified and Advanced Method | Using the simplified method for complex ship configurations in which its underlying assumptions no longer hold | Evacuation analysis not representative of actual behaviour in an emergency | View page → |
| Passenger Ship Safety Certificate: The Twelve-Month Renewal Survey Regime | PSSC renewal survey planned last-minute, without integration into the ship's general operating calendar | Operational pressure and risk of impact on scheduled passenger service | View page → |
| Gangway Operations | Material errors include treating 600 mm as a universal operational clearance; linking a net only to water; assigning PPE an independent universal date; imposing a security configuration absent from the SSP; or treating ladder and winch as one lifting appliance. | See the linked page for conditions, consequences and preventive measures. | View page → |
| Tender Operations: Service Boats for Passenger Transfer | Presenting the MSC.1/Circ.1417 risk assessment and log as universal obligations | Recommendatory guidance is converted into a Convention requirement beyond its scope | View page → |
| Passenger Accounting: The Accuracy of the Roll-Call after Costa Concordia | Counting of those present at assembly stations left to individual initiative, without a written and assigned procedure | As in the Costa Concordia case, inability to establish with certainty who is actually present or missing | View page → |
| Crowd Management: Managing the Flow to Assembly Stations | Emergency exercises conducted only with linear routes and cooperative passengers, without panic or misunderstanding scenarios | Crew unprepared for actual passenger behaviour in a real emergency | View page → |
| Cabin Safety: Stateroom Security Requirements under the CVSSA | Ineffective visual identification or alternative means lacking documented review | Possible USCG finding: assess the functional requirement and installed solution | View page → |
| The Onboard Medical Centre: Between MLC and Voluntary Standards | Presenting ACEP as a general legal requirement | Confusion between binding requirements and a voluntary standard | View page → |
| Turnaround Operations | Recurring errors are leaving interfaces unassigned or imposing names and controls absent from the SMS. Identify the responsible person, stop-work authority and the risk criterion actually applicable. | See the linked page for conditions, consequences and preventive measures. | View page → |
| North-East Atlantic ECA | SOx correctly deferred, NOx overlooked: the twelve-month suspension does not cover Tier III. | See the linked page for conditions, consequences and preventive measures. | View page → |
| Integrated Bilge Water Treatment System | Errors: treating a draft as current law; installing or modifying routes without approval; equating working equipment with permitted discharge; denying or making the voluntary Statement of Fact mandatory. | See the linked page for conditions, consequences and preventive measures. | View page → |
| Marine Plastic Strategy and Pellet Code | Avoid waiting until 2030 for the plastics prohibition, using the GRB as the only loss notification, always requiring below-deck stowage without the safe guidance alternative, or presenting the future code as in force or bringing the EU maritime branch forward to 2027. | See the linked page for conditions, consequences and preventive measures. | View page → |
| NOx Technical Code: Certification of Ammonia and Multi-Fuel Engines (MEPC 84) | Engine Family is not Engine Group: section 7.2 does not admit the former. | See the linked page for conditions, consequences and preventive measures. | View page → |
| New 2026 ECAs: Canadian Arctic and Norwegian Sea | Do not confuse the NOx date in 2026 with SOx/PM in 2027 or with the North-East Atlantic calendar. | See the linked page for conditions, consequences and preventive measures. | View page → |
| SOPEP — Shipboard Oil Pollution Emergency Plan | Emergency contacts not updated | Delayed notification in a real spill | View page → |
| Crew Fatigue: The IMO 2026-2027 Review Process | Formally tidy but inaccurate records | Fatigue and breaches remain hidden | View page → |
| Corrective and Preventive Action (CAPA) | Corrective action addressing the symptom, not the root cause | The NC recurs in similar form | View page → |
| Cyber Risk Management in the SMS (MSC.428(98)) | Cyber risk managed as a separate IT matter, not integrated into the SMS's general risk assessment | Lack of integrated documentary evidence in the event of an audit, despite the existence of technical IT measures | View page → |
| Designated Person Ashore (DPA) | DPA without real access to senior management | Ineffective escalation and possible NC | View page → |
| Document of Compliance (DOC) and Safety Management Certificate (SMC) | Confusing DOC annual and SMC intermediate checks | Missed verifications and validity not assured; possible enforcement | View page → |
| Emergency Preparedness and Contingency Plan | Drill reduced to an announcement without required elements | Preparedness not demonstrated | View page → |
| Crew Familiarisation and Training | Signature without checking understanding | Nominal preparation only | View page → |
| Internal SMS Audit | Independence not assessed and no justification of a §12.5 exception | Objectivity not demonstrated | View page → |
| Management Review | Review without evidence of evaluation | SMS effectiveness not demonstrated | View page → |
| Autonomous Ships (MASS): the Company's Responsibility under the SMS | MASS responsibility allocated generically to the DPA | Monitoring and operational control become confused | View page → |
| Pilot Transfer Arrangements: The New SOLAS V/23 Performance Standard | New construction for delivery from 2028 planned without specifying compliance with the new performance standard to the shipyard | Devices compliant only with the old version of Regulation V/23, to be upgraded later at additional cost | View page → |
| Ship Fuel Safety: Flashpoint Declaration | Bunkering started without having received the supplier's signed declaration on the flashpoint | Non-compliance with the new SOLAS requirement and risk of fuel with an unverified flashpoint on board | View page → |
| Emergency Generator Test | Test limited to the start alone, without verifying the actual load pick-up | Hidden faults only emerge during a real emergency or a thorough inspection | View page → |
| GMDSS (Global Maritime Distress and Safety System) | Radio tests performed at a supposedly universal interval or by a universal method | Test inconsistent with applicable instructions or inappropriate on-air call | View page → |
| Lifeboat Inspection (Inspection and Maintenance of Life-Saving Boats) | Crew on board during under-load release tests not specifically established as safe | Risk of serious or fatal injury in the event of a hook malfunction | View page → |
| Passage Planning | Passage plan drawn up only for the open-sea route, not berth-to-berth | Critical port manoeuvring phases not adequately planned | View page → |
| Fraudulent Certificates and Registrations: Paris MoU Guidance under Development | Treating the announced guidance as already published | Unverifiable indicators and procedures are attributed to it | View page → |
| Pre-PSC Checklist | Checklist applied only when an inspection is considered 'likely' | Pre-existing deficiencies remain undetected at port calls perceived as low risk | View page → |
| Concentrated Inspection Campaigns (CIC) | No specific preparation ahead of an announced CIC | A more thorough inspection on the topic catches the crew unprepared | View page → |
| Detention and Banning | Treating every detention as automatically causing more frequent or detailed inspection | The profile is predicted without applying its calculation | View page → |
| Documentation Required on Board | On-board certificate copy not updated after renewal or audit | Inconsistent documentation during inspection | View page → |
| Ship Risk Profile and New Inspection Regime (NIR) | Using a Paris MoU profile or window for a Tokyo MoU call | Priority and expected date may be wrong | View page → |
| VDES and NAVDAT: the Next Generation of Digital Maritime Communications | Equipping for every RMSS or accepting an MSI gap based on dissemination rules | Incorrect configuration or compliance assessment | View page → |
| Next-Generation ECDIS: the S-100 Framework | Saying no mandatory date fixed, presenting S-57 as the sole future basis, or turning 2029 into mandatory retrofit of every existing ECDIS. | Incorrect operational decision or regulatory status | View page → |
| Anchoring and Anchor Watch | Chain paid out according to a fixed generic rule, without considering forecast weather/sea conditions | Insufficient anchor holding if conditions deteriorate | View page → |
| Pilotage and Under Keel Clearance in Restricted Areas | Attributing a simplified UKC formula directly to SOLAS V/34 or treating the pilot as a transfer of ship responsibility. | Incorrect operational decision or regulatory status | View page → |
| VDR (Voyage Data Recorder) | Annual performance test not carried out or overdue | PSC deficiency, risk that the VDR will not function correctly when needed | View page → |
| Navigation in Restricted Visibility | Reducing Rule 19(d) to do not alter towards a contact forward of the beam, omitting the second branch, or treating darkness as a standalone restricted-visibility category. | Incorrect operational decision or regulatory status | View page → |
| Watchkeeping | Treating 12 hours as the only possible arrangement or, conversely, inferring the waiver automatically from a short distance. | Incorrect operational decision or regulatory status | View page → |
| Ammonia Engines: Safety and Reliability of the First Units in Service | Confusing the three interim instruments, imposing 1 July 2028, or citing first ships/commercial service without owner/yard/class source and status. | Non-compliant decision or treatment | View page → |
| Bunkering Operations and Fuel Quality Control | Attributing the checklist to MARPOL, checking only ≥60°C on the BDN, or treating 43°C emergency generator as the sole branch below 60°C. | Non-compliant decision or treatment | View page → |
| Cyber Risk Management of Automation Systems | Wrong cyber version or scope | Controls and evidence demanded from the wrong ship | View page → |
| Blackout and Failure Management | Defining 45 seconds as a universal monthly measurement/record or ignoring passenger/cargo/configuration differences. | Non-compliant decision or treatment | View page → |
| Critical Spare Parts Management | Critical spares list not updated after changes to the identified critical equipment | Missing spares for equipment recently classified as critical | View page → |
| Fire Pumps and Fixed Systems in the Engine Room | Emergency pump test conducted using the same power supply as the main engine room | The test does not genuinely verify the emergency condition the pump is designed for | View page → |
| Purifiers and Separators (Fuel Oil / Lube Oil Purifiers) | Changing settings without fuel data and maker instructions | Ineffective or unstable separation | View page → |
| Remote Inspection Techniques (RIT): Drone and ROV Inspections | Accepting generic drone certification as approval for every activity, losing finding locations or confusing published revisions with revisions already applicable. | Check the individual ship’s requirements and documents before closing the work. | View page → |
| Bottom Survey and In-Water Survey (IWS) | Applying I/10 to every SOLAS ship, using Z10 as the general IWS source, or calling every IWS Extended Dry-Docking. | Non-compliant decision or treatment | View page → |
| Coating and PSPC (Performance Standard for Protective Coatings) | Writing other spaces or double-side/bottom without scope, or making newbuilding PSPC mandatory for every repair. | Non-compliant decision or treatment | View page → |
| Dry Dock Entry Planning | Cargo regime used for passenger ship | Wrong due date or method | View page → |
| Thickness Measurement (Ultrasonic Thickness Measurement, UTM) | Applying Z10.1–Z10.5 to every ship or transferring substantial-corrosion definitions outside ship/survey scope. | Non-compliant decision or treatment | View page → |
| Survey in Dry Dock | Using Special/Renewal as one survey or presenting UR Z17 Rev.22 as already operative in 2026. | Non-compliant decision or treatment | View page → |
| Rudder and Sea Chests (Sea Chests and Sea Valves) | Saying necessarily dry dock or always open every sea chest/valve while ignoring surveyor and approved IWS/EDD. | Non-compliant decision or treatment | View page → |
| The IP Code: the Industrial Personnel Safety Certificate | Counting only IP, saying authorisations cease to apply, or using one transition for cargo and HSC. | Non-compliant decision or treatment | View page → |
| Annual Survey | Reducing the survey to paperwork, ignoring modifications or confusing a future BWM amendment with an effective requirement. | Check the individual ship’s requirements and documents before closing the work. | View page → |
| Condition of Class and Recommendations | Marking a finding closed solely on the yard’s statement or treating an extension request as authorisation. | Check the individual ship’s requirements and documents before closing the work. | View page → |
| Harmonized System of Survey and Certification (HSSC) | Treating printed expiry as the only relevant date or using an extension as an ordinary planning allowance. | Check the individual ship’s requirements and documents before closing the work. | View page → |
| International Load Line Certificate | Reducing all causes of invalidity to the need for increased freeboard. | Check the individual ship’s requirements and documents before closing the work. | View page → |
| Remote Survey Guidance: Remote Survey, ISM Audits and ISPS Verifications | Confusing eligibility of an individual item with eligibility of the entire survey; extending DOC exceptions to shipboard audits; treating remote ISPS verification as routine; routinely recording interviews. | Incomplete or unacceptable verification; loss of confidentiality. | View page → |
| Renewal Survey and Certificate Renewal | Confusing booking, completion and certificate issue; adding one and three months as available tolerance. | Check the individual ship’s requirements and documents before closing the work. | View page → |
| Tonnage Certificate and IMO Number | Confusing GT with tonnes of weight, assuming unlimited validity after alterations or requesting a new ship IMO number for flag transfer. | Check the individual ship’s requirements and documents before closing the work. | View page → |
| IMO Net-Zero Framework | Writing MEPC 84 approved detailed implementation guidelines or prices have been set. | Non-compliant decision or treatment | View page → |
Every operational page has a recurring-mistakes section: this page reproduces one entry and links to the full discussion.
Entries aligned with the recurring-mistakes sections of the linked pages on 16 September 2026. The Consequence / prevention column describes effects or preventive measures according to the source; this is not a statistical ranking.
Last substantive revision: 16 September 2026 · page fingerprint 963138db1869