Learning

# Mistake Library Live

The archive of the most common mistakes, with the typical consequence and a link to the page explaining how to avoid them.

Topic | Mistake | Typical consequence |
--- | --- | --- | ---
Oil Record Book | Entry not signed by the Master | PSC deficiency, possible detention | View page →
Sludge Management | Sludge balance with an unexplained discrepancy | Suspicion of illegal discharge | View page →
Bilge Water | Manual bypass of the OWS alarm system | Environmental offence, detention | View page →
Garbage Record Book | Garbage Management Plan not updated after the 100GT threshold change | Deficiency for ships 100-400GT | View page →
Incinerator | Incineration while in port | Local/Annex VI violation | View page →
Ballast Water | Using the old BWRB format after 1 February 2025 | PSC deficiency | View page →
Fuel Changeover | Changeover started too late relative to the ECA boundary | Annex VI deficiency | View page →
MARPOL Annex VI | Voyage plan not updated with the new ECAs (Mediterranean, Arctic/Norway) | Non-compliant fuel used in an area now regulated | View page →
Non Conformity | NC closed without verifying the effectiveness of the corrective action | The root cause remains and the NC recurs | View page →
Near Miss | Punitive culture toward those who report a close call | Reporting rate collapses, useful information is lost | View page →
Fire Drill | Drill run as a simple announcement, without practical use of the equipment | Crew unprepared for a real emergency | View page →
ECDIS | Anti-grounding alarms disabled to reduce false alarms | Loss of ECDIS's main safety function | View page →
Musters | New crew member not familiarised within the required 2 weeks | PSC deficiency, real risk in an emergency | View page →
Deficiency Management | Deficiency rectified but not linked to the SMS NC/CAPA system | The root cause remains unresolved, risk of recurrence | View page →
Communicating with the PSCO | Prepared, uniform answers from the whole crew, perceived as insincere | The PSCO extends the inspection beyond what was expected | View page →
Enclosed Space Entry | Entry without an instrumental atmosphere test | Real risk of death, among the most severe on board | View page →
COLREG | Crossing a TSS at an angle not close to 90° | Risk of collision with lane traffic | View page →
Bridge Resource Management | No check that the team shares the same mental model of the situation | Decisions made on different information bases among team members | View page →
Planned Maintenance System | Standby equipment not tested because it is 'not in use' | A failure of the primary unit reveals that the standby unit doesn't work either | View page →
Tail Shaft Survey | Continuous monitoring (CMS) data collected but not systematically analysed | Deterioration trend not detected in time | View page →
HSSC | Intermediate Survey conducted outside the 3-month window allowed around the anniversary date | Certificate endorsement not valid, PSC deficiency | View page →
EEXI/EPL | Engine Power Limitation chosen without assessing its impact on maximum commercial speed | Reduced operational flexibility discovered only afterwards | View page →
Sewage Management | Distance from shore estimated instead of GPS-verified before an untreated discharge | Violation of MARPOL Annex IV Regulation 11 | View page →
Bunker Delivery Note | MARPOL sample not taken with a traceable procedure at the time of bunkering | Unable to demonstrate fuel compliance in case of a dispute | View page →
MLC Complaint Handling | Complaint procedure not clearly explained to the seafarer on joining | MLC deficiency in a PSC inspection | View page →
Permit to Work | Hot work permit left open beyond the maximum 12-hour validity | Work in progress without valid formal authorisation | View page →
Ship Security Plan/ISPS | SSO certificate expired or not on board at the time of inspection | Automatic grounds for detention under the 2025 PSC procedures | View page →
Liferaft/EPIRB | 12-month liferaft maintenance interval exceeded | Serious deficiency, possible detention | View page →
USCG Port State Control | Assumption that Paris/Tokyo MOU compliance is enough for US calls too | Unpleasant surprise when facing USCG-specific, non-harmonised requirements | View page →
Tokyo MOU | Ballast Water Management System (BWMS) not checked before a call in the Asia-Pacific region | Deficiency in the category most frequent in the 2025 CICs | View page →
Ro-Ro Cargo Securing | Standard number of lashing points applied without considering the vehicle's actual centre of gravity | Insufficient lashing for vehicles with a high centre of gravity | View page →
Reefer Container Monitoring | Temperature checks logged generically, without hourly detail | Unable to demonstrate the real extent of a deviation in a dispute | View page →
Cargo Claim Handling | No reservation noted on the bill of lading despite non-compliant conditions at loading | Presumption of carrier liability for pre-existing damage | View page →
Polar Waters Passage Planning | Voyage plan for polar waters reusing the standard passage planning approach | Failure to consider ice, SAR capability and places of refuge | View page →
GNSS Resilience | Exclusive reliance on GNSS position without cross-checking in areas of known risk | Use of a spoofed position without timely detection | View page →
VTS Traffic Management | VTS guidance perceived as binding orders rather than information/assistance | Suboptimal navigational decisions without the Master's full critical assessment | View page →
Boiler Operations | Safety device checks limited to a visual inspection, without testing under operating conditions | Safety valve malfunction not detected until a critical event | View page →
Refrigeration Plant | No advance planning for the transition to low-GWP refrigerants | Supply difficulties as regulatory deadlines approach | View page →
Engine Room Energy Efficiency | Engine performance deterioration attributed generically to 'wear' without checking hull/propeller fouling | Hull cleaning not scheduled in time, growing impact on consumption | View page →
Anchor Chain Cable Survey | Only the most visibly worn links renewed instead of the whole affected length | Non-compliance with the length-based renewal rule | View page →
Cargo Hold Survey Bulk Carrier | Coating condition assessed as 'POOR' but not logged or re-examined at the Annual Survey | Non-compliance with IACS UR Z11 rev.7 | View page →
Shipyard Waste Management | Blasting residue containing organotin compounds treated as generic shipyard waste | Risk of environmental contamination of the shipyard site | View page →
Safety Construction/Equipment/Radio | Anniversary dates of the three certificates not synchronised under the HSSC cycle | Unnecessary back-to-back surveys and risk of a missed deadline | View page →
ISPS Certification | ISSC intermediate audit scheduled right up against the deadline of the window between the 2nd and 3rd anniversary | Risk of missing the required window | View page →
MLC Certification | DMLC Part II not updated following changes to onboard procedures | Discrepancy found during inspection between the declared document and actual practice | View page →
BWM Convention In Depth | BWMS commissioning test documentation not systematically kept on board | Unable to demonstrate actual operational compliance if checked | View page →
Biofouling Management | In-water cleaning performed by services without a containment and capture system for residues | Release of invasive organisms and antifouling paint residues into the environment | View page →
Underwater Radiated Noise | Propeller cavitation not monitored as a primary source of underwater noise | Failure to identify an easily correctable cause | View page →
Anti-Fouling Systems | Cybutryne removal postponed beyond the 60-month limit since last application | Non-compliance with the maximum deadline set by the 2021 amendments | View page →
VOC Management Plan | Crew not specifically trained on VOC procedures, confused with general cargo procedures | Incomplete application of emission-minimisation measures | View page →
Management of Change | Changes implemented informally without a structured assessment process | Risks associated with the change not identified before implementation | View page →
Dangerous Goods Manifest | Manifest not updated after changes to the actual stowage plan | Wrong information on the location of dangerous goods in an emergency | View page →
Lithium Batteries | Battery fire handled with conventional firefighting techniques | Ineffective extinguishing and risk of reignition | View page →
IMDG Training | Generic training for the whole crew without distinguishing the three required levels | Personnel with direct responsibilities not adequately prepared | View page →
Watertight Doors | Watertight doors kept open while underway for ease of passage | Watertight subdivision defeated in the event of a sudden breach | View page →
Helicopter Operations | Refuelling carried out without dedicated firefighting personnel present | Critical response time lost in the event of ignition during refuelling | View page →
Black Sea MOU | Preparation based only on Paris MOU statistics, without considering regional specifics | Underestimation of the real inspection/detention risk in the region | View page →
Indian Ocean MOU | Breadth and variety of member states underestimated in voyage planning | Calls at member states of the regime not recognised as such | View page →
Heavy Lift Cargo | Standard CSS lashing tables applied by analogy to a non-standardised cargo | Underestimation of the actual forces acting on the cargo and insufficient lashing | View page →
BNWAS | System handled as a mechanical formality, automatic reset without real vigilance verification | The system loses its function of genuinely verifying the officer's active presence | View page →
IoT Predictive Maintenance | Sensors installed but data collected without systematic trend analysis | Impending failure not anticipated despite the instrumentation being available | View page →
Boiler Water Treatment | Daily TDS/chloride/phosphate tests skipped for lack of time | Corrosion or scale formation not detected in time | View page →
Shipyard Repair Contracts | Generic repair specification developed without a detailed analysis of the ship's actual condition | Additional work negotiated under unfavourable contractual conditions during execution | View page →
Multi-Class Survey | Bilateral Agreement between the two Classification Societies not checked before planning the survey cycle | Duplicated surveys or coverage gaps between the two class societies | View page →
Statement of Compliance for Temporary Lay-up | Essential checks neglected during lay-up on the assumption the ship is 'non-operational' and therefore low risk | Undetected deterioration that lengthens the reactivation survey | View page →
Digital Statutory Certificates | Electronic certificate treated as a simple PDF scan, without the required technical safeguards | The document is not recognised as the legal equivalent of the paper certificate | View page →
Onboard Carbon Capture and Storage | Investment in an OCCS system based on the expectation of an immediate EEXI or CII credit | Regulatory expectations disappointed, since the credit is not yet recognised | View page →
Shore Power and Cold Ironing | Port call planning based only on the regulatory obligation, without checking actual OPS infrastructure availability | Unable to connect to OPS despite the obligation | View page →
Wind-Assisted Propulsion Systems | WAPS technology chosen without assessing the wind conditions of the actual operating routes | Actual fuel savings significantly below expectations | View page →
Solid Bulk Dangerous Cargoes (IMSBC) | Shipper's moisture content certificate accepted without independent verification in case of doubt | Cargo with moisture above the TML loaded without the risk being detected | View page →
MARPOL Annex III | 'MARINE POLLUTANT' marking not applied because deemed redundant with the primary IMDG class labelling | Non-compliance with MARPOL Annex III even when the IMDG safety classification is correct | View page →
Polar Waters Discharges | Only the standard MARPOL rules applied during a polar waters transit, without considering Polar Code Part II-A | Discharge non-compliant with the stricter restrictions specifically applicable in polar waters | View page →
Contractor Management | Supplier/contractor engaged without a documented, verifiable qualification procedure | Major non-conformity in an audit when evidence of qualification is requested | View page →
Whistleblowing | Whistleblowing channel not kept distinct from ordinary reporting channels | The reporter does not perceive a safe alternative when ordinary channels are inadequate | View page →
Immersion Suits | Number of immersion suits on board not checked against the number of boats and the actual crew carried | Insufficient coverage in a real abandon-ship situation | View page →
Fixed CO2/Water Mist Firefighting Systems | CO2 recharge reserve kept at 50% instead of the required 100% | Unable to mount a second full intervention if the fire reignites | View page →
Escape Routes | Category A machinery space escape routes checked only for their formal existence, without verifying true independence | Both escape routes potentially compromised by the same event | View page →
Appeal Against a Detention | Correcting deficiencies postponed pending the outcome of the appeal | Unnecessarily prolonged ship detention, since the detention is not suspended during the appeal | View page →
Flag State-PSC Coordination | SSO certificate validity not systematically checked before a security inspection | Automatic detention under Appendix 20, regardless of the ship's other conditions | View page →
Break Bulk Cargo | Over-stowing applied without checking the discharge order of subsequent ports | Cargo restowing and damage during intermediate discharge | View page →
Charter Party and Cargo Clauses | Safe port/safe berth clause accepted without a specific check of the nominated port's conditions | Contractual liability for a port that turns out to be unsafe | View page →
Icebreaker Convoy Navigation | Safe distance from the icebreaker set independently instead of following convoy command instructions | Risk of collision with re-formed ice or other convoy vessels | View page →
ECDIS Datum Shift and Chart Reference | GPS position shown by the ECDIS trusted without checking the cell's datum notes | Positional error not detected in areas with an unknown or unreliable WGS84 conversion | View page →
Integrated Automation and UMS | UMS regime kept active despite a critical alarm flagged as unverifiable | Loss of the equivalent safety required by SOLAS II-1 Part E without anyone noticing until a real event | View page →
Engine Room Digital Twin | Investment in a digital twin platform without a sufficiently mature sensor infrastructure | Simulation model fed by insufficient data, with unreliable predictions | View page →
Post-Repair Warranties | Warranty claim notified after the contractual deadlines | Claim rejected regardless of the technical merit of the defect | View page →
Sister-Ship Dry Dock Planning | Each ship in the series treated as an isolated case, without reusing lessons learned from the previous cycle | Known recurring issues on the series rediscovered from scratch at every dry dock cycle | View page →
Interim Certificates | Planning for the definitive certificate's audit/survey started too late relative to the interim's expiry | Real risk of the interim certificate expiring before the definitive one is ready | View page →
Class-Statutory Survey Coordination | Class and statutory surveys planned separately despite falling within the same HSSC window | Doubled operational disruption and extra cost for two separate surveyor visits | View page →
Methanol/Ammonia Bunkering | Planning based on theoretical technical compatibility, without checking actual bunkering availability along the routes | Practically unable to refuel the ship according to the original voyage plan | View page →
Just Transition and Decarbonization | Crew training on alternative fuels planned only right before the new ship's delivery | Crew unprepared for the ship entering service, with real operational risk | View page →
EU MRV Review | Scope of the MRV Regulation checked only once and never updated over time | A ship that falls into a recently included category without the Company noticing | View page →
IMO DCS Transport Work | Data collection systems upgrade postponed, relying only on the mandatory 2026 deadline | Systems not ready in time, risk of non-compliance at the deadline | View page →
Prevention of Violence and Harassment | PSSR training renewed without checking that it includes the new competency required from 2026 | Certification formally completed but not compliant with the new STCW requirements | View page →
Master's Authority | The Master's overriding authority documented in the SMS but not concretely upheld when it carries a commercial cost | Erosion of the Master's trust in the system | View page →
Ro-Ro and Vehicle Spaces | Keel-laying date not checked to determine the applicability of the new 2026 requirements | Detection system design not compliant with the applicable requirements | View page →
SOLAS II-1/3-13 Lifting Appliances | Non-commercial lifting appliances not identified as subject to the new regime | Non-compliance discovered only at the Renewal Survey | View page →
Mediterranean MOU | Paris MOU statistics and priorities applied uncritically to calls in the Med MoU region | Preparation not calibrated to the real regional specifics | View page →
Bulk Carrier PSC | PSC preparation focused only on the structural/ESP component, neglecting ISM and maintenance | Detention for the deficiency categories that remain the most frequent in the segment | View page →
BLU Code | Ship/shore information exchange form filled in as a formality without checking it is actually applied | Actual loading sequence different from the one agreed, with structural risk | View page →
Containers Lost at Sea | Container loss reported only internally within the Company, without the notifications required by SOLAS from 2026 | Non-compliance with the new obligation, risk not flagged for other ships | View page →
STCW Simulator Training | Certification paths planned around a sea service/simulator substitution not yet in force | Certification path non-compliant with the STCW requirements currently applicable | View page →
MASS Code | MASS Code assumed to already be binding on all autonomous ships from 2026 | Incorrect regulatory planning relative to the actual legal status | View page →
Methanol Engines | Spare parts for methanol engines managed with the same logistics as conventional or LNG engines | Delays in the availability of critical specific spares, with prolonged machinery downtime | View page →
BESS Battery Rooms | Battery room treated as a generic extension of the engine room in the emergency plan | Inadequate response strategy in the event of thermal runaway | View page →
Hong Kong Convention IHM | IHM Part I treated as a document to prepare only close to final recycling | Difficult and imprecise retroactive reconstruction of the hazardous materials history | View page →
Next-Generation Coatings | Coating choice based only on immediate application cost, without considering the total life-cycle | Higher total life-cycle cost, more frequent dry dockings than necessary | View page →
Shipyard Hot Work Permit | Ship and shipyard permit systems not formally aligned before hot work begins | Confusion over responsibility and level of control, risk of safety gaps | View page →
Flag Change | Flag change completed without ensuring continuity of statutory certificate validity | Documentary gap period in which the ship operates without fully valid certificates | View page →
HSSC-Vetting Coordination | HSSC calendar and vetting inspection calendar managed separately without being shared | Unintended concentration of surveys and vetting inspections in the same time window | View page →
CII Reduction Factors | Revised SEEMP Part II not ready in time for the 1 January 2026 deadline | Documentary non-compliance with the new CII requirements | View page →
Class 7 Radioactive Materials | Approval from coastal states along the route requested too late relative to departure | Significant operational delay, unable to depart on schedule | View page →
General Cargo Dangerous Goods | Segregation categories applied without considering the absence of a container's physical enclosure | Physically insufficient segregation distance in the hold | View page →
Safe Return to Port | SRtP system redundancy considered only at the design stage, without verifying it is maintained operationally over time | Degradation of the real return-to-port capability relative to the original design | View page →
Passenger Musters | Old muster rule of 'within 24 hours of departure' applied, superseded since 2015 | Non-compliance with SOLAS III/19, passengers without instructions for a leg of the voyage | View page →
Ro-Ro Passenger Damage Stability | Operating limits of one sister ship applied assuming the same stability regime | Actual operating limits of the ship exceeded, reduced safety margin | View page →
Gastrointestinal Outbreak | Waiting until the 3% threshold is reached before stepping up cleaning and surveillance | Failure to prevent progression to a formal outbreak | View page →
SAR Cooperation Plan | SAR cooperation plan developed once and never updated again | Plan no longer consistent with the actual operating area or available SAR services | View page →
Persons with Reduced Mobility | Accessibility requirements considered limited to the physical dimension only, ignoring the EAA's digital scope | Ticketing/information systems non-compliant with requirements binding since 2025 | View page →
Evacuation Analysis | Simplified method used for complex ship configurations where its assumptions no longer hold | Evacuation analysis not representative of real emergency behaviour | View page →
Passenger Ship Safety Certificate | Annual PSSC survey planned last-minute, without integration into the general operating calendar | Operational pressure and risk of impact on scheduled passenger service | View page →
Gangway Operations | Access ladder used without checking that the actual angle is within the indicated maximum/minimum limits | Structural stress not anticipated by the design, risk of failure | View page →
Tender Operations | Lifejackets left stowed during tendering without a documented risk assessment | Operating practice with no documentary basis, indefensible in the event of an incident | View page →
Passenger Accounting | Counting of those present at muster stations left to individual initiative, without a written procedure | As in the Costa Concordia case, unable to establish who is present or missing | View page →
Crowd Management | Drills conducted only with linear routes and cooperative passengers, without panic scenarios | Crew unprepared for real passenger behaviour in an emergency | View page →
Cabin Safety (CVSSA) | CVSSA cabin compliance checked only generically, without verifying the exact technical specifications | Technical non-compliance detectable in a targeted USCG inspection | View page →
Medical Centre | Medical centre's clinical operating standards not aligned with the industry's reference ACEP guidelines | Medical centre below the standard the industry effectively expects | View page →
Turnaround Operations | No Simultaneous Operations Leader designated to coordinate conflicting turnaround activities | Coordination responsibility diffused, impacts not managed promptly | View page →
North-East Atlantic ECA | Passage planning and chart updates postponed close to the entry-into-force date (1 September 2027) | Risk of sailing in the new ECA without properly planned changeover procedures | View page →
Integrated Bilge Water Treatment System | Engine room personnel trained only on the traditional separator+alarm architecture, without updating for the installed integrated system | Inadequate handling of anomalies or alarms specific to the integrated system | View page →
Marine Plastic Strategy and Pellet Code | Container transport of plastic pellets handled with the same generic practices as any other dry cargo | Risk of massive dispersal at sea if the container is lost | View page →
Crew Fatigue | Rest hour logging treated as a mere documentary formality, without reflecting real fatigue management on board | Formal compliance that fails to prevent chronic fatigue build-up in the crew | View page →
Pilot Transfer Arrangements | Newbuildings with delivery from 2028 planned without specifying compliance with the new performance standard to the yard | Equipment compliant only with the old version of Regulation V/23, requiring later upgrade at extra cost | View page →
Fuel Safety and Flashpoint | Bunkering started without having received the supplier's signed flashpoint declaration | Non-compliance with the new SOLAS requirement and risk of fuel with an unverified flashpoint on board | View page →
Fraudulent Certificates and Registrations | Post-flag-change documentation treated as an administrative formality, without a thorough consistency check across the new certificates | Documentary inconsistencies flagged by the PSCO, triggering extra scrutiny even without a real irregularity | View page →
VDES and NAVDAT | Satellite equipment verified as compatible only with the historically contracted RMSS service, without a multi-RMSS check | Risk of missing critical MSI information transmitted via a different RMSS service | View page →
Next-Generation ECDIS S-100 | Investment in new ECDIS equipment planned without checking the supplier's S-100 compatibility roadmap | Risk of equipment needing early replacement ahead of its expected life cycle | View page →
Ammonia Engines | Crew training on alternative fuels treated generically, without distinguishing the specific protocols for ammonia's toxicity | Inadequate response in the event of release or exposure, given the different risk profile | View page →
Remote Inspection Techniques (RIT) | RIT survey planned using an operator not verified as formally approved by the ship's own Classification Society | Risk that the survey is not recognised as valid for class purposes | View page →
IP Code (Industrial Personnel) | Pre-existing authorisation before 1 July 2024 assumed valid indefinitely, without planning the transition to the IP Code | Authorisation lapses at the next survey without an Industrial Personnel Safety Certificate ready | View page →
IMO Net-Zero Framework | Fleet planning based on the original entry-into-force date without monitoring slippages in the adoption process (the October 2025 session closed without agreement) | Fuel/compliance credit investments calibrated to a regulatory timeline that is no longer current | View page →

Every operational page in the MARPOL Operations module includes its own "Recurring mistakes" table in a dedicated section; this page collects them all into a single searchable index.

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