2025 MARPOL VI Port State Control: Complete Inspection Guide

Port State Control (PSC) inspections are the frontline enforcement measure for MARPOL Annex VI. In 2025, PSC officers apply MEPC.321(74) and IMO Resolution A.1185(33) to verify compliance with sulphur limits, NOx/Tier requirements, fuel oil quality, EGCS operation and record keeping. Preparing proactively reduces inspection time, avoids detainable findings and keeps schedules on track.

Document readiness is the foundation of every Annex VI inspection. Officers will request the IAPP Certificate and Supplement, EIAPP Certificates and Technical Files for engines over 130 kW, representative bunker delivery notes with retained samples, the Ballast/fuel changeover procedures where relevant, and EGCS manuals and monitoring records if an exhaust gas cleaning system is fitted. Electronic record systems are acceptable only with explicit flag-state approval — always keep printed backups and exportable logs.

Fuel compliance checks are central. Inspectors compare bunker delivery notes against IAPP supplements and fuel samples. Proper sampling, retention and matching commercial documents demonstrate chain-of-custody; weak or inconsistent paperwork frequently triggers detailed inspections. In Emission Control Areas (ECAs), the stricter 0.10% m/m sulphur limit applies and crews must document timely fuel changeovers with flushing records and timings.

EGCS-equipped vessels face focused scrutiny: officers inspect installation conformity with approved documentation, verify monitoring and tamper-proof data logging, and review washwater parameter records where applicable. Ensure pH, turbidity and PAH monitoring results are logged and that maintenance and calibration records are current. Poor EGCS monitoring or obvious tampering is a detainable deficiency.

NOx/Tier verification matters where Tier III controls apply. Engines subject to Tier III rules require EIAPP Certificates and Technical Files that match the installed configuration. Officers will review log entries demonstrating compliant operational modes and recording on/off status in Tier zones. Unexplained mode changes, missing records or unauthorized engine modifications can lead to prolonged inspections and enforcement action.

Clear grounds for extended inspection include missing/invalid certificates, inconsistent bunker documentation, evidence of non-compliant fuel use (including remote sensing reports), crew unfamiliarity with fuel changeover procedures, and malfunctioning pollution control equipment. Portable fuel analysers and remote sensing increasingly feed PSC risk profiles — robust records are the best defence against escalation.

Fuel non-availability claims are tightly scrutinised. Masters must document voyage planning, procurement attempts, supplier contacts and efforts to find compliant fuel. Cost alone is not a valid justification; evidence of good-faith efforts and alternative plans (e.g., shore treatment, retention, or planned bunkering at the next port) support legitimate claims. Notify flag and port authorities promptly when compliant fuel cannot be sourced.

Operational practice: run pre-arrival audits 48–72 hours before port arrival. Verify certificate expiries, export bunker-sample data for immediate presentation, test EGCS monitoring systems, and rehearse crew briefings on ECA changeover routines. Mock interviews with key officers reduce the risk that PSC requests for clarifications turn into inspection escalations.

Detainable deficiencies under Annex VI carry real commercial and reputational costs. Missing IAPP/EIAPP certificates, evidence of non-compliant fuel use, disabled or bypassed EGCS equipment, and falsified monitoring logs are among the clearest grounds for detention. Maintain clear maintenance histories, calibration records and an auditable chain-of-custody for bunker samples to demonstrate compliance quickly.

Best-practice checklist: 1) ensure all Annex VI certificates and engine Technical Files are onboard and valid; 2) retain representative bunker samples with documented chain-of-custody; 3) keep EGCS and NOx monitoring and maintenance logs current and accessible; 4) produce written fuel changeover procedures in the crew working language; 5) train bridge and engineering teams on inspection routines and documentation presentation.

Finally, embrace digital readiness but retain physical backups. Electronic certificates and monitoring speed inspections when properly authorised; without Administration approval, they complicate PSC interactions. With remote sensing and portable testing tools becoming commonplace, the operator that documents thoroughly and trains its crew most effectively will experience the shortest inspections and the least operational disruption under MARPOL Annex VI enforcement in 2025.