What Regulation 11 says
MARPOL Annex I Regulation 11 sits in Chapter 2 of the consolidated Annex, the chapter that runs Regulations 6 through 11 and covers surveys and certification. Regulations 6 to 8 govern the flag-State surveys; Regulations 9 and 10 govern the issue, duration, and validity of the International Oil Pollution Prevention Certificate; Regulation 11 is the last regulation in the chapter and the only one that hands inspection power to a State other than the flag State. The numbering is from the consolidated Annex I that took effect on 1 January 2007 under the revised Annex adopted by resolution MEPC.117(52); earlier editions carried the same operational-PSC provision under a different number, so older textbooks and case files sometimes cite it differently. The provision itself dates back to the operational-requirements amendments of the early 1990s that put crew competence, not just shipboard hardware, within reach of a visiting inspector.
The operative text is narrow and deliberate. A ship, when in a port or an offshore terminal of another Party, is subject to inspection by officers duly authorized by that Party concerning operational requirements under the Annex where there are clear grounds for believing that the master or crew are not familiar with essential shipboard procedures relating to the prevention of pollution by oil. Two phrases do the work. “Operational requirements” widens the inspection past the paper that Regulations 9 and 10 produce. “Clear grounds” gates it: the officer can’t open an operational inspection on a hunch, but specific evidence unlocks the engine room and the crew. Where the officer then confirms the unfamiliarity, the Party shall take steps to ensure the ship does not sail until the situation has been brought to order in accordance with the requirements of the Annex.
Regulation 11 is short because it isn’t meant to stand alone. It borrows the machinery of MARPOL Article 5 and Article 6, which let a Party inspect a foreign ship and detain it, and it points the inspector at the substantive Annex I duties: the discharge limits of Regulation 15 and Regulation 34, the recording duty of Regulation 17 and Regulation 36, and the emergency-plan duty of Regulation 37. What Regulation 11 adds is the right to test whether the crew can actually do those things, witnessed, on the day, in the machinery space.
Why a separate operational hook was needed
Before operational PSC existed, a port State’s reach under Annex I effectively stopped at the certificate. Article 5(2) of MARPOL had always allowed a port State to verify that a ship carries a valid IOPP Certificate and, absent that certificate or with clear grounds that the ship’s condition or equipment doesn’t correspond substantially to its particulars, to inspect further and detain. That is a condition-and-equipment power. It catches a ship whose separator is physically missing or visibly broken. It does not catch the far more common failure: equipment that exists, passes a static check, and would never be operated correctly at sea because nobody on board has been trained to run it.
Regulation 11 closes that gap. The drafters recognized that the oily water separator and the oil discharge monitoring and control system are only as good as the watchkeeper standing in front of them at 0300 with a bilge well filling and a heavy sea running. An inspector who can only read the IOPP supplement learns that a Type-approved 15 ppm separator is fitted. An inspector empowered by Regulation 11 can ask the duty engineer to start it, line it up, and explain what the three-way valve does when the effluent exceeds 15 parts per million. The first inspection verifies a fact about the ship. The second verifies a fact about the crew. Operational PSC is the recognition that pollution prevention is a procedure performed by people, not a property of steel.
The operational-requirements amendment of 1994
Operational PSC wasn’t in the original Annex I. The 1973 Convention and the 1978 Protocol gave port States the Article 5 and Article 6 powers over certificates, condition, and equipment, but said nothing about crew competence. The change came with the package of amendments the Marine Environment Protection Committee adopted in the early-to-mid 1990s to add port State control on operational requirements across the MARPOL annexes, the same move that put parallel provisions into Annex II, Annex III, Annex V, and later Annex VI. The amendments entered force in the mid-1990s and, for the first time, let a visiting officer treat a crew’s unfamiliarity with essential procedures as an inspectable, detainable failure in its own right.
The timing wasn’t accidental. The same years produced the International Safety Management Code, made mandatory through SOLAS Chapter IX and entering force for the first ship categories on 1 July 1998, which placed shipboard procedures and crew familiarization at the center of safe operation. Operational PSC and the ISM Code grew from the same recognition: that the human element, not just the steel, determines whether a ship pollutes. An operational PSC officer today reads the ISM familiarization records as part of testing Regulation 11 compliance, because the Code requires the company to ensure new crew are familiarized with their duties, including the pollution-prevention procedures Regulation 11 tests. The two instruments interlock by design.
Certificate PSC versus operational PSC
The distinction between document inspection and operational inspection is the practical core of Regulation 11, and it maps onto two different sets of evidence an officer looks at on board.
Certificate and document PSC is the baseline that every Annex I inspection starts with. The officer examines the IOPP Certificate and its attached Supplement, the Record of Construction and Equipment, to confirm the certificate is in date, issued by or on behalf of the flag Administration, and that the equipment listed matches what is fitted. The officer reviews the Oil Record Book Part I (machinery-space operations) and, on a tanker, Part II (cargo and ballast operations) for completeness, signatures, and internal consistency. On a tanker the officer also looks for the cargo-area discharge controls of Regulation 34 and, where fitted, the crude oil washing operations and equipment manual. This is the work that 33 CFR 151.23 codifies for the US Coast Guard: the required documents during a port-State inspection include the IOPP Certificate, the Oil Record Book, and the Shipboard Oil Pollution Emergency Plan. A ship can pass every line of this and still be a polluter.
Operational PSC under Regulation 11 is the layer that sits on top, triggered by clear grounds. Here the officer stops reading and starts watching. The question changes from “is the equipment certified and the book signed” to “can this crew operate the equipment and keep the book truthfully under real conditions.” The officer may ask the engineer to demonstrate the oil filtering equipment, to show how the 15 ppm bilge alarm and the automatic three-way stopping valve respond, to explain the oil discharge monitoring and control system on a tanker, and to walk through the SOPEP response to a bunker spill. Familiarity is the test. A separator that the crew can’t prime, an alarm whose test button nobody can find, an ORB entry that contradicts the sounding log: each is an operational failure that a pure certificate inspection would have missed.
The two layers are not equal in what they reveal. Certificate PSC is necessary and fast; operational PSC is slower, needs trained inspectors, and is where the serious findings live. The magic-pipe cases that have produced the largest MARPOL fines were almost never caught by a document inspection alone. They were caught when an inspector cross-checked the ORB against tank soundings, noticed the separator’s running hours didn’t match the volumes recorded, and pulled the floor plates. That is operational PSC working as Regulation 11 intended.
The clear-grounds standard
Clear grounds is the gate, and it is defined, not left to the officer’s mood. The IMO Procedures for Port State Control, 2025, adopted by resolution A.1206(34) at the IMO Assembly’s 34th session and in effect from 1 January 2026, set out the clear-grounds list that PSC officers work to. A.1206(34) revoked the previous Procedures for Port State Control, 2023 (resolution A.1185(33), adopted 6 December 2023), which in turn had replaced the 2021 procedures in resolution A.1155(32). The 2025 revision is the current instrument, and it carries the same Annex I guidance in its appendices on investigations and inspections under MARPOL, with an added appendix of guidance for officers on security aspects. Authors and trainers citing “the PSC procedures” should name A.1206(34) now, not the older numbers, though the substance of the clear-grounds test for Annex I has been stable across editions.
For Annex I operational inspections, the clear grounds that justify going past the certificate include an absent, incomplete, or improperly maintained Oil Record Book; evidence that the master or crew are not familiar with essential shipboard procedures relating to the prevention of pollution by oil; evidence from the ship’s own logs that quantities of oil or oily mixtures have been discharged in contravention of the Annex; and physical signs of an illegal discharge, such as oil on the hull or in the water around the ship, or piping arrangements that don’t match the Record of Construction and Equipment. The presence of bypass piping around the separator is the most damning single clear ground there is. So is an ORB whose machinery-space entries can’t be reconciled with the bilge and sludge tank capacities.
The standard matters because it is the difference between a lawful inspection and an arbitrary one. A port State can’t simply decide to put every foreign engine crew through an operational drill; the no-more-favorable-treatment principle (below) and the trade cost of unjustified detentions both push against that. Clear grounds give the inspection a defensible trigger. When a port State detains a ship on an operational deficiency, the clear ground that opened the inspection is part of the record, and the flag State and the owner can test it. This is why the Procedures appendices are written as inspection checklists keyed to specific observations rather than as open grants of discretion.
From clear grounds to a more detailed inspection
The inspection follows a defined escalation: initial inspection, clear grounds, more detailed inspection, deficiencies, and, where warranted, detention. The initial inspection is the boarding and document review every ship gets. If nothing during that review amounts to a clear ground, the inspection closes. If a clear ground surfaces, the officer is entitled, and under the Procedures expected, to carry out a more detailed inspection, which for Annex I means the operational checks of Regulation 11. The more detailed inspection produces findings graded by severity. A minor finding is recorded and rectified before departure. A finding that makes the ship unseaworthy from a pollution standpoint, or that shows the crew can’t run essential equipment, becomes a detainable deficiency.
The grading isn’t ad hoc either. The Procedures and the regional MoU guidance carry detention criteria for Annex I that name the conditions warranting detention: oil filtering equipment, the 15 ppm alarm, or the automatic stopping device inoperative; the oil discharge monitoring and control system on a tanker inoperative; the crew unfamiliar with essential pollution-prevention operations; and the absence of a valid IOPP Certificate. The officer maps the finding to the criterion and the detention follows from the rule, not from discretion. That structure is what gives Regulation 11 its teeth while keeping it inside the bounds of due process.
The equipment behind the inspection
Regulation 11 is abstract until you stand in front of the hardware it tests. Three systems carry most operational Annex I inspections, and an officer’s questions are built around them.
The oily water separator, governed by Regulation 14, processes machinery-space bilge water so the effluent contains no more than 15 parts per million of oil before any overboard discharge. Every ship of 400 gross tonnage and above must have one. The associated 15 ppm bilge alarm monitors the effluent continuously, and the automatic three-way valve must stop the overboard discharge and recirculate the flow back to a holding tank whenever the alarm trips. The discharge limit of 15 ppm is the number the entire system exists to hold, and it is the number an officer will ask the engineer to explain.
The oil discharge monitoring and control system, governed by Regulation 31, is the tanker-side equivalent for cargo-tank and slop-tank effluent. It records and controls the instantaneous rate of discharge of oil per nautical mile and the total quantity discharged, and it must stop the discharge when the permitted rate is exceeded under Regulation 34. On a tanker an operational inspection reaches the ODMCS as well as the separator, because the cargo-area discharge controls of Regulation 34 are where the larger pollution risk sits.
The Oil Record Book is the written trace of all of it. Regulation 17 requires Part I, the machinery-space record, on every ship of 400 gross tonnage and above; Regulation 36 requires Part II, the cargo and ballast record, on oil tankers of 150 gross tonnage and above. Every transfer, every separator run, every overboard discharge, every landing of sludge to a reception facility must be entered and signed. The ORB is the document that operational PSC interrogates hardest, because it is where a dishonest crew most often leaves the inconsistency that betrays the bypass.
Practical inspection scenarios
What an officer actually does under Regulation 11 is concrete, and the scenarios below are the standard sequence a competent inspector runs once a clear ground has opened the operational inspection.
Testing crew familiarity with the oily water separator
The officer asks the duty engineer to start and line up the separator as if processing bilge water for overboard discharge. The tells are immediate. An engineer who hesitates at the suction valves, can’t say which tank the effluent recirculates to on an alarm, or doesn’t know the unit’s Type-approval limit is showing unfamiliarity, which is itself a clear ground confirmed. The officer watches whether the crew runs the separator regularly or treats it as a museum piece. A separator with a film of dust on the control panel, valves seized from disuse, and a running-hours counter that hasn’t moved in months tells the officer the bilges are being managed some other way. The other way is usually overboard.
The 15 ppm alarm gets its own check. The officer asks for a demonstration of the alarm test and watches the three-way valve operate. The valve must drive the discharge back inboard when the alarm sounds. If the test button does nothing, if the valve is wired or pinned in the overboard position, or if the crew can’t produce the alarm’s calibration record, the operational finding is serious and likely detainable. A defeated alarm is the signature of a magic-pipe operation, because the whole point of bypassing the separator is to discharge oily water that would have tripped the alarm.
Reading the Oil Record Book against reality
The ORB check is where document PSC and operational PSC meet. The officer doesn’t just confirm the book is signed; the officer reconciles it. Bilge and sludge tank soundings get compared against the entries: a tank that the book says was emptied to a reception facility should show the corresponding drop, and a separator run recorded for a given duration should match the running-hours counter. Continuity is the test. When recorded tank levels jump without an entry to explain them, or when the volume of sludge generated by the main engine over a voyage doesn’t reconcile with what the book says was burned in the incinerator or landed ashore, the officer has found the inconsistency that operational PSC exists to find.
The reconciliation can be quantitative. An engine of known power produces sludge at a broadly predictable rate, and over a long voyage the ORB should account for that volume through incineration, settling, or landing ashore. A book that shows almost no sludge generation on a high-powered ship that has been at sea for weeks is recording a fiction. The officer who notices this has a clear ground, and the clear ground justifies pulling floor plates and tracing piping, which is where bypass hoses get found.
Walking the SOPEP and the spill response
The officer also tests the crew against the SOPEP. The question is operational, not documentary: not “do you have a plan” but “what do you do, right now, if a bunker hose bursts at this berth.” The officer expects the crew to know who they call first, where the SOPEP locker is, what’s in it, and how the deck scuppers are plugged during bunkering. A crew that can produce the plan but can’t name the local response contact or find the absorbent material is showing the same unfamiliarity Regulation 11 targets. The SOPEP drill record under the ISM Code gives the officer a second cross-check: a plan that has never been exercised on board is a clear operational weakness.
Tanker-specific operational checks
On an oil tanker the operational inspection reaches further than the engine room, because the cargo and ballast operations carry the larger pollution risk. The officer who has clear grounds can test the crew against the cargo-area discharge controls of Regulation 34, which permit a tanker to discharge cargo-tank effluent outside special areas only when the ship is more than 50 nautical miles from the nearest land, proceeding en route, and the instantaneous rate of discharge of oil content doesn’t exceed 30 liters per nautical mile, with a total quantity cap tied to the cargo carried. These are operational thresholds, and the question is whether the crew understands and applies them through the oil discharge monitoring and control system of Regulation 31, not whether they can recite them.
The ODMCS itself is the focus. The officer may ask the officer of the cargo watch to demonstrate how the system records the instantaneous rate, how it computes the running total, and what it does when the rate exceeds the Regulation 34 limit: it must stop the discharge automatically. A crew that can’t show the ODMCS in a working state, or that keeps the system in manual override, is failing the operational test as surely as an engine crew that can’t run the separator. On a tanker fitted for crude oil washing, the officer can also probe whether the crew operates COW in accordance with the approved Operations and Equipment Manual, because COW interacts with the slop-tank and discharge arrangements the ORB Part II records.
The slop-tank and load-on-top regime is the other tanker-specific area an operational inspection can reach. The crew should be able to explain how oily residues are retained in the slop tanks, how the oil-water interface is determined before any discharge, and how the Oil Record Book Part II entries for ballasting, cleaning, and discharge reconcile with the slop-tank soundings. The reconciliation logic is identical to the machinery-space ORB check: the book has to match the tanks. A tanker ORB Part II that records discharges the slop-tank volumes can’t support is the same red flag on the cargo side that a magic-pipe inconsistency is on the engine side.
Detention, recognized organizations, and no more favorable treatment
Three structural features of the PSC regime shape how Regulation 11 findings are handled.
Detention is the enforcement end of the operational inspection. When a more detailed inspection confirms a detainable Annex I deficiency, the port State detains the ship until the deficiency is corrected. The detention criteria for Annex I are specific: inoperative oil filtering equipment, a defeated or inoperative 15 ppm alarm or automatic stopping device, an inoperative ODMCS on a tanker, crew unfamiliarity with essential pollution-prevention procedures, and the absence of a valid IOPP Certificate. Regulation 11’s own text reinforces this: where the master or crew are not familiar with essential shipboard procedures, the Party shall ensure the ship doesn’t sail until the situation is brought to order. The detention isn’t a penalty in itself; it’s a hold that lifts when the ship is again capable of operating without presenting an unreasonable threat of harm to the marine environment.
Recognized organizations sit on both sides of the inspection. The classification societies acting as ROs issue the IOPP Certificate and conduct the Annex I surveys on behalf of flag Administrations under Regulations 6 to 10. A PSC officer who finds a serious operational deficiency on a ship the RO recently surveyed has, in effect, found a gap in that RO’s survey performance, and the MoU regimes track RO performance partly through PSC detention statistics. The RO that certified the separator as compliant didn’t put the watchkeeper in front of it who couldn’t run it. That is the structural limit of survey-based assurance and the reason operational PSC exists as an independent check.
No more favorable treatment is the principle that makes the whole regime enforceable against the world’s fleet. Under MARPOL Article 5(4), a ship flying the flag of a State that is not a Party to MARPOL gets no more favorable treatment in a port of a Party than a ship that is. A non-Party ship can’t escape operational PSC by pointing out it isn’t bound by Annex I; the port State applies the same standard to it. Without this principle, owners could reflag to non-Party States to dodge inspection, and the operational-requirements check would erode. The principle is why a port State’s Regulation 11 inspection bites regardless of the ship’s flag.
Regional regimes and concentrated inspection campaigns
Regulation 11 is the treaty authority; the regional MoUs are how it operates at scale. The Paris MoU and the Tokyo MoU are the two largest, covering the waters of Europe and the North Atlantic, and the Asia-Pacific, respectively. Each runs a shared inspection database, a ship-targeting system that selects which ships to inspect based on risk profile, and a harmonized set of deficiency codes that classify every finding. An Annex I operational deficiency found under Regulation 11 is recorded against its deficiency code and, where detainable, drives the ship’s company and flag performance metrics that feed back into targeting. The general port-State-control regime, its targeting logic, and the MoU detention statistics are covered in the dedicated articles; the point here is that the MoUs operationalize the Regulation 11 power rather than create it.
The concentrated inspection campaign is the tool the MoUs use to focus operational PSC on a theme for a fixed window, usually three months, often run jointly by Paris and Tokyo. During a MARPOL-themed CIC, inspectors work to a standard questionnaire that pushes them past the certificate and into the operational checks Regulation 11 authorizes: whether the crew can operate the separator, whether the 15 ppm alarm functions, whether the ORB reconciles. The CIC concentrates inspector attention and produces a dataset on a single compliance area across thousands of ships, which the MoUs publish. The campaigns are where Regulation 11’s operational reach gets exercised most deliberately, because the questionnaire is built to test familiarity rather than read paperwork.
Deficiency codes give the regime a common language. A finding of inoperative oil filtering equipment, an ORB not properly maintained, or crew unfamiliar with pollution-prevention procedures each carries a code that maps to the MARPOL regulation breached and to a severity that determines whether the ship is detained. The codes are what let a deficiency found in Rotterdam and one found in Singapore count the same way against a ship’s history. That common classification is what turns scattered inspections into the risk-targeting and company-performance signals the MoUs run on.
The enforcement chain: from inspection to prosecution
Operational PSC under Regulation 11 is the front end of an enforcement chain that, at its far end, has produced some of the largest environmental fines in shipping. The chain runs from the clear ground, through the ORB inconsistency, to the bypass discovery, to the criminal charge.
The mechanism is the Oil Record Book itself. MARPOL requires every machinery-space oil transfer and discharge to be entered, so an ORB that omits an illegal overboard discharge, or papers it over with a false entry, is itself a MARPOL violation independent of the discharge. In the United States this is the jurisdictional key. The Act to Prevent Pollution from Ships, the domestic statute implementing MARPOL at 33 U.S.C. chapter 33, lets US authorities prosecute on the basis of a false ORB presented to the Coast Guard in a US port, even when the discharge happened in international waters. The discharge may be beyond US jurisdiction; the false book presented in port is not. Nearly every magic-pipe case pairs an APPS count with false-statement and obstruction charges under 18 U.S.C. 1001 and 18 U.S.C. 1519, prosecuted by the Department of Justice Environmental Crimes Section.
The technical signature is consistent across cases. Engineers bypass the separator with a temporary hose, the magic pipe, usually a length of flexible hose with welded flanges that discharges oily bilge water directly overboard, unmonitored. To create a paper record that hides the missing waste, some run sea water through the separator so the running-hours and the alarm log show plausible activity. The discrepancy that betrays the operation is the one operational PSC is built to find: the ORB entries don’t reconcile with the tank soundings, the separator hours, or the sludge the engine must have produced. A whistleblower tip, often from a crew member who recorded the bypass on a phone, frequently supplies the clear ground that opens the inspection, and the US APPS whistleblower provision lets a court award up to half of any fine to the informant, which sharpens the incentive.
The discharge limits these prosecutions enforce are the ones in Regulation 15 for machinery-space bilge water and Regulation 34 for tanker cargo-area effluent, recorded under Regulations 17 and 36. Regulation 11 is the inspection authority that exposes the breach; Regulations 15 and 34 are the substantive limits breached; Regulations 17 and 36 are the recording duties the false entry violates. The four regulations work as a chain, and operational PSC is the link that connects the equipment in the engine room to the courtroom.
How operational PSC interacts with the flag-State survey cycle
Operational PSC and the flag-State survey cycle are meant to be complementary, and understanding the seam between them explains why Regulation 11 is an independent check rather than a duplicate of certification. The flag State, or its recognized organization, surveys the ship under Regulations 6 to 10: an initial survey before the IOPP Certificate is issued, periodical surveys, intermediate surveys, and an annual survey, with the certificate valid for a period not exceeding five years. Those surveys verify the equipment and, to a degree, its function. They are scheduled, announced, and conducted with the ship’s cooperation. The separator is tested with the crew expecting the test.
Operational PSC is the opposite in every respect that matters for catching the determined offender. It is unannounced, conducted by a State with no commercial relationship to the ship, and triggered by clear grounds an experienced inspector spots on the day. A separator that passes its annual survey because it was primed and run correctly for the surveyor can still fail an operational PSC inspection three months later when the duty engineer who actually keeps the watch can’t run it. The survey verifies a capability existed once; operational PSC verifies the capability is exercised continuously by the people on watch. The two checks answer different questions, and a regime that relied on surveys alone would have a structural blind spot that operational PSC fills.
The interaction also disciplines the recognized organizations. When a ship is detained on an Annex I operational deficiency shortly after a survey by an RO, the MoU records it, and patterns of post-survey detentions feed the performance assessment of that RO. The Paris MoU publishes RO performance tables built partly on this data. An RO whose surveyed ships are detained more often than the fleet average faces scrutiny from the flag Administrations that delegate to it. Operational PSC, in other words, is not just a check on individual ships; it is a feedback signal on the quality of the survey regime that certified them, and that signal is one of the few independent measures of RO performance the system has.
Documentary cross-checks an officer reconciles
The reconciliation work at the heart of operational PSC deserves to be stated as the specific cross-checks an officer runs, because the discipline is what separates a real operational inspection from a glance at the paperwork. The officer holds several records side by side and looks for the entry that doesn’t fit.
The first cross-check is the Oil Record Book against the bilge and sludge tank soundings. Every machinery-space transfer and discharge under Regulation 17 has to appear in the book, and the recorded tank levels have to move in step with those entries. A sludge tank the book says was landed to a reception facility should sound near empty; a tank that sounds full against a book showing repeated discharges is recording fiction. The second cross-check is the separator’s running-hours counter against the ORB entries for separator operation: the recorded runs and the counter should agree, and a counter frozen against a book full of separator entries means the entries are invented. The third is the engine’s expected sludge production against the total accounted for in the book through incineration, settling, and landing ashore, a quantitative check an engineer-inspector can do from the engine’s power and the voyage length.
The fourth cross-check brings in the other shipboard documents 33 CFR 151.23 lists for a US inspection: the incinerator log and the SOPEP. The incinerator log should account for sludge the ORB says was burned; a log showing little incineration against an ORB claiming heavy incineration is another inconsistency. The SOPEP’s drill record, kept under the ISM Code, shows whether the crew has actually exercised the plan operational PSC tests. Each document is a partial record of the same physical reality, and the offender who falsifies one usually can’t keep all of them consistent. The officer’s skill is in finding the document that wasn’t falsified to match, because that is the one that exposes the others.
Limitations
Regulation 11 is a strong tool with real boundaries, and a practitioner-grade account has to name them.
It depends entirely on clear grounds. The provision gives no power to run an operational inspection on a ship that presents a clean certificate, a well-kept ORB, and no physical signs of a problem. A skilled crew that bypasses the separator and falsifies the book consistently can pass an initial inspection. Operational PSC catches the careless and the unlucky more reliably than the disciplined offender, which is why whistleblowers, not inspectors, trigger many of the largest cases. The clear-grounds gate that protects honest ships from arbitrary inspection also shields the competent polluter.
It depends on inspector skill and time. Reconciling an ORB against tank soundings and engine sludge production takes a trained engineer-inspector and more time than a document check. A port running high traffic with a thin inspectorate will do fewer operational inspections and more certificate checks. The quality of Regulation 11 enforcement varies with the port State’s resources, and the regime accepts that unevenness as the price of a worldwide port-based system.
It is an inspection power, not a prosecution power. Regulation 11 lets a port State detain and require correction; it does not by itself impose a fine. Penalties flow from the port or flag State’s domestic law, and those vary widely. The large fines come from jurisdictions like the United States that criminalize the false ORB; a port State without comparable domestic legislation may be able to detain but not to punish. The deterrent strength of the operational-PSC chain is uneven across the world for that reason.
It can’t reach a discharge in another State’s waters directly. The treaty splits enforcement: the coastal State has jurisdiction over a discharge in its own waters, the flag State over its ships everywhere, and the port State over the condition and operation of ships in its ports. Regulation 11 is the port-State slice. Its power over a high-seas discharge is indirect, working through the ORB and the no-more-favorable-treatment principle rather than through any direct authority over the discharge event itself. That indirect reach is what makes the Oil Record Book, and the honesty of the entries in it, the center of gravity for the whole enforcement scheme.
See also
- MARPOL Annex I: the full Annex, its chapters, and the regulation map
- MARPOL Convention: the parent instrument and Articles 5 and 6 that supply the inspection and detention powers
- Port State control: the general PSC regime, targeting, and MoU structure
- Paris MoU and Tokyo MoU: the regional regimes and their inspection databases
- International Oil Pollution Prevention Certificate: the document certificate PSC verifies
- Regulation 14: oil filtering equipment and Regulation 31: ODMCS: the equipment operational PSC tests
- Regulation 15 and Regulation 34: the discharge limits enforced
- Regulation 17 and Regulation 36: the Oil Record Book recording duties
- Regulation 37: SOPEP: the emergency plan tested in an operational inspection