A valid certificate is not the same as a compliant ship. A chemical tanker can hold a current International Certificate of Fitness, pass every scheduled survey, and still pump a Category X residue over the side because the duty officer skipped the prewash to make the tide. The survey scheme catches the first failure; it cannot catch the second. Port State control on operational requirements is the rule built to catch the second. It lets a port State officer go past the paperwork and into the operation: ask the cargo engineer to describe the stripping sequence, read the Cargo Record Book against the approved Procedures and Arrangements Manual, and decide whether the crew on board this week can actually do what the certificate says the ship can do.
There is a numbering point to settle before anything else, because the assigned topic carries a number that the treaty does not use for this annex. In the revised MARPOL Annex II adopted by Resolution MEPC.118(52) on 15 October 2004, in force 1 January 2007, the operational-control function is not a Regulation 11. It is part of Regulation 16, “Measures of control by port States,” which is the whole of Chapter 6 of the Annex. The operational-requirements limb, with its “clear grounds” test and its no-sail duty, is paragraph 16.9 within that regulation. The “Regulation 11” title that reads “Port State control on operational requirements” belongs to MARPOL Annex I, the oil annex; Annex III places the same wording in its Regulation 8, and Annex VI in its Regulation 10. The substance is the same across all four annexes. Only the regulation number changes. This article uses the correct Annex II citation, Regulation 16, throughout, and flags the cross-annex numbering where it helps.
The two halves of MARPOL Annex II compliance
MARPOL Annex II splits compliance into two mechanisms that are easy to confuse and important to keep apart. The first is the survey-and-certificate scheme. Regulations 8, 9 and 10 of the revised Annex set out the surveys (initial, renewal, intermediate and annual) and the issue and endorsement of the certificate that records them. This half is flag-State-led, scheduled, and condition-based. It asks one question: was the ship built and equipped, and is it maintained, to the standard the Annex and the IBC Code require for the cargoes it is certified to carry? When that question is answered yes, the flag State or its recognized organization issues the certificate, and the certificate is the portable proof of it.
The second mechanism is port State control, and it asks a different question. Not “was the ship built right” but “is the crew running it right, today, in this port.” That half is port-State-led, unscheduled, and operation-based. It does not wait for a survey window; it happens whenever a foreign ship calls and an officer decides to look. It does not assume the certificate settles the matter; it treats the certificate as a starting point and tests the operation behind it. The legal home of that second mechanism in Annex II is Regulation 16.
The distinction matters because the failure modes are different. A survey deficiency is usually a thing: a corroded pipe, a missing valve, a pump that no longer strips to the rated rate, a tank coating that has broken down. An operational deficiency is usually a practice: a prewash that was logged but not done, a Cargo Record Book entry that does not match the shore tank figures, a crew that has never opened the P&A Manual to the section that governs the cargo they just discharged. The survey scheme cannot see the practice, because the practice happens between surveys, on voyages the surveyor never sails. Regulation 16 exists to put an inspector on board during the practice, or close enough after it that the record still tells the truth.
That is also why a clean certificate does not end a Regulation 16 inspection. The certificate proves the ship was compliant at the moment of survey. It is silent on every operation since. An officer who finds the structure and equipment in order has confirmed the survey half; the operational half is still entirely open. The two halves are deliberately separate so that neither can be used to excuse the other.
The treaty hooks: MARPOL Articles 5 and 6
Regulation 16 does not float free. It sits on two articles of the parent MARPOL Convention that give every Party the underlying power to inspect and to act. Without them, the annex regulations would be standards with no enforcement reach into a foreign ship.
Article 5 is the certificate-and-inspection article. It provides that a certificate issued under the authority of a Party shall be accepted by the other Parties and regarded as having the same validity as a certificate issued by them. That mutual recognition is the thing that makes a single survey by one flag State good in every port. But Article 5 carries the qualification that makes port State control possible. A ship required to hold a certificate is, in the ports of other Parties, subject to inspection by officers duly authorized by that Party. That inspection is limited to verifying that there is on board a valid certificate, unless there are clear grounds for believing that the condition of the ship or its equipment does not correspond substantially with the particulars of that certificate. The “clear grounds” phrase that governs the whole operational-control regime starts here, in the treaty, before it is repeated in the annex regulation.
Article 6 is the detection-and-enforcement article. It opens with a duty: Parties shall co-operate in the detection of violations and the enforcement of the provisions of the Convention, using all appropriate and practicable measures of detection and environmental monitoring, adequate procedures for reporting, and accumulation of evidence. It then grants the inspection power directly: a ship to which the Convention applies may, in any port or offshore terminal of a Party, be subject to inspection by officers appointed or authorized by that Party for the purpose of verifying whether the ship has discharged any harmful substances in violation of the Annexes. Where the inspection turns up a violation, the Party either takes proceedings under its own law or furnishes the flag State with the evidence it has, and the flag State then investigates and may prosecute.
The two articles divide the work. Article 5 covers the standing condition of the ship against its certificate; Article 6 covers a specific suspected act of pollution and the evidence trail behind it. A Regulation 16 inspection of a chemical tanker can engage both: the officer checks the certificate and the ship’s condition under the Article 5 limb, and, if the Cargo Record Book or a shore observation suggests an illegal discharge of noxious liquid substance residue, the Article 6 enforcement machinery opens. The no-more-favourable-treatment principle, also in the Convention, closes the obvious gap: a ship flying the flag of a State that is not a Party to MARPOL gets inspected against the same standard, so that registering under a non-Party flag buys no relief.
Regulation 16 and the “clear grounds” threshold
Regulation 16 of the revised Annex II is short, and its operational-control limb is shorter still, but it carries the whole of the mechanism this article is about. The regulation establishes that a ship required to hold a certificate is, when in a port of another Party, subject to inspection by authorized officers, that the inspection is in principle limited to confirming a valid certificate is on board, and that the officer may go further on clear grounds. The further step is the operational check. 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 noxious liquid substances, the officer may examine those procedures. If the ship is found not to conform, or the crew is found not familiar, the Party shall ensure that the ship does not sail until the situation has been brought to order.
“Clear grounds” is the hinge, and it is not a low bar of suspicion alone. The IMO Procedures for Port State Control define it as evidence that the ship, its equipment, or its crew does not correspond substantially with the requirements of the relevant convention, or that the master or crew are not familiar with essential shipboard procedures relating to safety or pollution prevention. The current edition, Resolution A.1185(33), “Procedures for Port State Control, 2023,” adopted on 6 December 2023, lists the kinds of evidence that meet it. For an Annex II operational check the examples include: certificates or other required documents that are absent, invalid, or manifestly do not match the ship; cargo or operational records that are incomplete or appear false; indications that the crew cannot communicate or cannot carry out essential operations; and information from a report or complaint that the ship has not complied with discharge or operational requirements.
The threshold does real work. Below it, the officer is confined to the certificate check, because the regime deliberately protects a ship with valid papers from open-ended interrogation. Above it, the whole operation is open: the officer can call for the P&A Manual, walk the Cargo Record Book entry by entry, ask the cargo engineer to talk through the last prewash, and require a demonstration of the stripping and discharge arrangement. The “clear grounds” finding is what converts a routine certificate check into an operational inspection, and a careful officer records exactly which evidence supplied the grounds, because that record is what justifies any detention that follows.
The no-sail duty is the teeth. Regulation 16 does not merely permit the officer to note a problem; where the ship or crew does not conform, it requires the Party to ensure the ship does not proceed to sea until it can do so without presenting an unreasonable threat of harm to the marine environment. The Procedures translate that into the detention decision: a deficiency serious enough to be detainable holds the ship until it is rectified and verified by re-inspection. A ship that is allowed to sail to a repair yard sails only to the nearest appropriate one, and only on conditions the port State sets.
What the officer actually inspects
The operational inspection of a chemical tanker under Regulation 16 is concrete. It is built around four things a competent crew can show and a non-compliant crew cannot: the Procedures and Arrangements Manual, the Cargo Record Book, the prewash and stripping operation, and the crew’s own familiarity with all three. Each is a separate line of evidence, and each can independently supply the clear grounds that open the rest.
The Procedures and Arrangements Manual
Every ship certified to carry noxious liquid substances in bulk carries an approved Procedures and Arrangements Manual, the P&A Manual, required by Regulation 14 of the Annex and approved by the Administration to the standard form set in Resolution MEPC.119(52). The manual is the ship-specific operating instruction for Annex II compliance. It identifies the cargo system, the pumping and stripping arrangement, the temperatures and procedures for unloading each category of cargo, the prewash procedures and when they apply, the ventilation procedure where that is used to clean a tank, and the discharge arrangements with the conditions that govern them. It is not generic. It is keyed to the actual piping, pumps, and stripping performance of the specific ship, measured and recorded at the stripping test.
The port State officer checks first that the manual is on board, is the approved version, and matches the ship. Then the officer checks that the operation actually followed it. This is where the manual becomes an inspection tool rather than a shelf document. The Cargo Record Book entries for the last few cargoes should trace back to the manual’s procedures; the discharge route used should be the one the manual specifies; the prewash, where one was required, should have run as the manual describes. A manual that is missing, superseded, or for a different ship is itself a deficiency. A manual that is present and correct but plainly not followed is a more serious one, because it shows the compliance regime existed on paper and was set aside in practice.
The Cargo Record Book
The Cargo Record Book is the operational ledger of Annex II, required by Regulation 15. Every loading, internal transfer, unloading, tank cleaning, prewash, ballasting of cargo tanks, discharge of ballast or cleaning water, and disposal of residue to a reception facility is logged, item by coded item, signed by the officer in charge and countersigned page by page by the master. The detail of what each operation requires lives in the Regulation 15 article; the point here is what a PSC officer does with it.
The book is the single most useful document in an operational inspection, because it is the crew’s own contemporaneous account of what they did, and it can be checked against independent evidence. The officer reads the entries for the recent cargoes and tests them three ways. Internal consistency: do the operations follow a coherent sequence, with each tank’s cycle complete and the entries dated and signed? Consistency with the manual: do the discharge and prewash entries match the procedures the P&A Manual prescribes for those categories? Consistency with the outside world: do the quantities and timings square with the cargo documents, the shore tank figures, the ullage records, and the receipts from reception facilities? A gap, a back-dated signature, an entry that records a prewash the reception-facility receipt does not corroborate, or a discharge logged in a position or at a speed the Annex does not permit: any of these is a deficiency, and a falsified entry is among the gravest, because it is not a lapse in operation but a concealment of one.
Prewash and stripping operations
For the higher-hazard cargoes the Annex requires physical operations the officer can ask the crew to evidence. A Category X residue must be prewashed to a reception facility before the ship leaves the port of unloading, with the wash continued until the concentration at the tank inlet is at or below the Annex limit and the tank is empty. Certain Category Y substances, the persistent floaters with high viscosity or a high melting point identified in IBC Code Chapter 17, attract a mandatory prewash of their own in designated areas. Stripping is the prior step: the cargo system must strip the tank down to the residual quantity the ship demonstrated at its stripping test, the figure recorded in the P&A Manual, before any prewash or discharge.
The officer checks the operations through their evidence trail rather than by watching them, since the ship is usually past the unloading by the time of inspection. The prewash shows up as a Cargo Record Book entry and a reception-facility receipt; the stripping performance shows up as the residual quantities the crew logged and as the demonstrated stripping figure in the manual. Where the call is at the unloading port and the operation is still live, the officer can observe directly: whether the prewash is actually running to the reception facility, whether the stripping is taking the tank down to the manual figure, whether the discharge arrangement is the approved one. A prewash that the records say happened but the receipts do not support, or a stripping performance that has plainly degraded below the demonstrated figure, is a deficiency that goes to the heart of the discharge-control regime in Regulation 13.
Crew familiarity
Underneath all three documents is the thing Regulation 16.9 names directly: whether the master and crew are familiar with the essential shipboard procedures relating to pollution prevention. This is tested by conversation and demonstration, not by paperwork alone. The officer asks the responsible officer to describe the discharge and prewash procedure for the cargo just carried, to locate the relevant section of the P&A Manual, to explain how the stripping system works and what residual quantity it achieves, and to walk through where each Cargo Record Book entry came from. A crew that runs the ship competently can do this without hesitation. A crew that cannot is itself the deficiency the regulation is written to catch, regardless of how tidy the documents look, because tidy documents maintained by a crew that does not understand them are exactly the gap between certificated condition and actual operation that Regulation 16 closes.
The IMO Procedures for Port State Control
Regulation 16 states the power and the threshold; it does not tell an officer in Rotterdam and an officer in Singapore how to apply them the same way. That harmonization is the job of the IMO Procedures for Port State Control, a free-standing Assembly resolution that all the annex PSC regulations point to. The current text is Resolution A.1185(33), “Procedures for Port State Control, 2023,” adopted by the IMO Assembly on 6 December 2023 and reissued with editorial corrections in March 2024. It replaced Resolution A.1155(32) of 2021, which had replaced A.1138(31) and, before that, the long-running A.1052(27) of 2011. Each revision folds in new convention requirements and tightens the deficiency guidance; the 2023 edition is the one a current inspection runs on.
The Procedures do several things the bare regulation cannot. They define the key terms, “inspection,” “more detailed inspection,” “valid certificate,” “detention,” and, importantly, “clear grounds,” so that the threshold means the same thing in every member port. They set out the inspection sequence: the initial inspection of certificates and overall condition; the move to a more detailed inspection when clear grounds appear; and the recording, in a standard report, of every deficiency and the action code attached to it. They carry, in their appendices, the operational-control guidelines that turn the abstract “essential shipboard procedures” into a checklist an officer can work through for each convention, including the Annex II prewash, discharge, P&A Manual, and Cargo Record Book items.
The appendices also define the detainable deficiency. A detention is the most serious routine PSC outcome short of a ban: the ship is legally prohibited from sailing until every detainable deficiency has been rectified and verified by re-inspection. The Procedures list the criteria. For operational compliance, a serious failure of an operational requirement, including a crew unable to carry out essential pollution-prevention operations, can itself ground a detention. The officer’s professional judgment governs the call, but it is judgment exercised against a documented standard, not at large. That documented standard is what lets a detention survive the appeal a shipowner is entitled to bring, and it is why the officer’s record of the clear grounds and the deficiencies is as important as the inspection itself.
The Procedures also impose discipline on the inspector. They carry a Code of Good Practice for PSC officers, set proportionality limits so that an inspection does not detain a ship for trivial faults, and require that a ship released from detention be re-inspected against the deficiencies that grounded the hold. The system is built to be repeatable and reviewable, because a port State acting on a foreign ship is acting at the edge of its jurisdiction, and the legitimacy of that action rests on its being done the same way everywhere and on the record.
The regional regimes: Paris MoU and Tokyo MoU
MARPOL gives every port State the power to inspect, but it does not tell them which ships to inspect or how to share what they find. Left to itself, that produces duplication, gaps, and ships that learn which ports to avoid. The regional memoranda of understanding on port State control fix that by coordinating the targeting and pooling the results across a whole region. The two largest and most developed are the Paris MoU and the Tokyo MoU, and between them they cover the busiest trading regions a chemical tanker calls at.
The Paris MoU binds 27 member maritime authorities across Europe and the North Atlantic coast of Canada. It is the older of the two and the more legally embedded, because its members that are EU states also operate inside the EU Port State Control Directive, which gives the regime statutory force, EMSA oversight, standardized officer training, and a banning power that reaches every EU port. The Tokyo MoU binds 21 member authorities across the Asia-Pacific, the largest region by traffic volume of any PSC regime. It operates by agreement rather than supranational directive, but its members enforce it in practice with the same machinery.
Both regimes run on the same targeting logic, the New Inspection Regime. Each ship that calls is assigned a Ship Risk Profile, computed from generic and historic factors: the ship type and age, the performance record of its flag, the performance record of its recognized organization, the company’s own inspection history, and the number and nature of deficiencies and detentions found at recent calls. A chemical tanker is in a higher-risk category by type alone, because the consequence of a cargo failure is large. The profile sorts ships into high, standard, and low risk, and that sorting sets how often a ship is inspected and how deeply. A low-risk ship may go many months between inspections; a high-risk ship faces an expanded inspection at a defined frequency, and a ship that combines a high-risk type with a poorly performing flag is at the top of the queue.
The flag performance that feeds the profile is itself published. Both MoUs maintain White, Grey and Black lists of flag States, ranked on the detention record of their fleets over a rolling three-year window. A White-list flag signals a fleet that performs well; a Black-list flag signals one that does not, and a ship on a Black-list flag is inspected harder, given shorter rectification periods, and is exposed to the banning mechanism after repeated detentions. Under the Paris MoU a ship that jumps a detention or fails to call at the indicated repair yard, or that flies a Black-list flag and has been detained more than once or twice in the preceding 36 months, can be refused access to every port in the region until the company proves to the authority’s satisfaction that the ship fully complies. The ban is the regime’s heaviest routine sanction, and it is the reason the New Inspection Regime’s risk targeting has real consequence rather than being a paperwork exercise.
The two regimes also run Concentrated Inspection Campaigns, periods, usually three months, in which every member authority adds a focused questionnaire on one topic to its routine inspections. The campaigns are chosen where deficiency data, new convention requirements, or accident patterns show a higher risk of non-compliance, and the Paris and Tokyo MoUs increasingly run them jointly: the 2024 campaign focused on crew wages and seafarer employment agreements under the Maritime Labour Convention, and the 2025 joint campaign covered ballast water management. A campaign turns a diffuse inspection effort into a measurement of one thing across thousands of ships in one season, and a campaign on cargo or pollution operations is the kind of exercise that puts the Annex II operational items, the P&A Manual, the Cargo Record Book, the prewash, directly in the inspector’s focus for that quarter.
Reporting and the feedback loop
A PSC inspection is not finished when the officer leaves the ship. The result is recorded in a standard inspection report, with each deficiency coded against the relevant convention and instrument and given an action code, from “rectify before departure” through “detainable” to “rectify within 14 days.” The report goes to the ship, and the data goes into the regional information system, the THETIS database for the Paris MoU and the APCIS database for the Tokyo MoU. That database is the memory of the regime. It is what the next port’s officer reads before deciding whether to inspect, and it is what feeds the Ship Risk Profile and the flag-performance lists.
The loop closes on the flag State and the recognized organization. A detention is reported to the flag State, which is obliged to investigate; a pattern of detentions on one flag moves it toward the Grey or Black list; a pattern on one recognized organization, the class society that surveyed the ship for the flag, counts against that organization in the risk profile and can trigger review of its authorization. So an operational deficiency found on one chemical tanker in one port is not a local event. It changes the risk score of that ship for its next call, it counts toward the standing of its flag and its class society, and it is visible to every other member authority in the region. The system is built so that a ship cannot shed a bad operational record by sailing to a different port, which is the gap that uncoordinated national enforcement always left open.
That feedback is also the link back to the survey scheme this article is careful to keep separate. An operational deficiency repeatedly found on the ships of one recognized organization is evidence that the organization’s surveys are not catching what they should, and the PSC data is one of the inputs the flag State and the IMO use to monitor recognized-organization performance. The two halves of compliance, the survey half and the port-State half, meet again in the data: the operational inspections test, in aggregate, whether the certificates the survey scheme issues are worth what they claim.
How this regulation differs from the rest of Annex II
It helps to place Regulation 16 against its neighbors, because the operational-control function is easy to blur into the regulations it draws on. The survey-and-certificate regulations, 8, 9 and 10, are the upstream half already described: they decide the ship’s certificated condition; Regulation 16 tests the operation behind that certificate. The discharge and prewash rule, Regulation 13, sets the substantive standard, the speeds, distances, depths, and prewash end points a discharge must meet; Regulation 16 is the inspection that asks whether the ship met it. The P&A Manual requirement, Regulation 14, and the Cargo Record Book requirement, Regulation 15, create the documents; Regulation 16 is where those documents are read against the operation and found true or false.
The cleanest way to hold the difference is by what each regulation produces. Regulation 13 produces a rule. Regulation 14 produces a manual. Regulation 15 produces a record. Regulation 16 produces a decision: inspect or not, detain or release, report and feed the result back into the regional system. The earlier regulations are the standards and the paperwork; Regulation 16 is the enforcement act that tests them on a specific ship on a specific day. This article deliberately does not re-derive the discharge numbers or the Cargo Record Book entry codes, because those belong to their own regulations and articles; the focus here is the enforcement mechanism that consumes them.
The cross-annex point bears one more mention because it is a frequent source of citation error. The function this article covers is, word for word, “Port State control on operational requirements” in Annex I, where it is Regulation 11, in Annex III where it is Regulation 8, and in Annex VI where it is Regulation 10. In Annex II the IMO chose a different structure: rather than a stand-alone operational-control regulation, it placed the operational-control limb inside the broader Regulation 16, “Measures of control by port States,” alongside the general inspection power. The wording of the operational check, the “clear grounds,” the familiarity test, the no-sail duty, is materially the same as in the other annexes. A reference that cites “Annex II Regulation 11” for this function is using the Annex I number by mistake; the correct Annex II citation is Regulation 16, and specifically paragraph 16.9 for the operational-requirements limb.
A worked inspection sequence
It is worth tracing one inspection end to end, because the parts only make sense in motion. A chemical tanker on a flag with a middling detention record calls at a Paris MoU port to load. Its Ship Risk Profile, set by its type, its age, its flag’s standing, and the deficiencies logged at its last two calls in the THETIS data, comes back as high risk and due for an expanded inspection. That is the targeting step: the ship was selected by the New Inspection Regime, not at random.
The officer boards and starts with the certificate. The International Certificate of Fitness is valid and matches the ship. Under Article 5 and the first limb of Regulation 16, that would ordinarily be the end of it. But the officer asks the cargo engineer to describe the prewash procedure for the last Category X cargo, and the engineer cannot say where the P&A Manual covers it or how the residue was landed. That is the “clear grounds” finding: the master or crew appear not familiar with an essential pollution-prevention procedure. It is recorded as the basis for going further.
The inspection now moves to the operation. The officer opens the Cargo Record Book and finds a prewash logged for the last Category X discharge, but the reception-facility receipt for that port is not in the file and the master cannot produce it. The P&A Manual is on board and is the approved version, but the discharge route the book records does not match the route the manual prescribes. Two deficiencies are now on the report: an incomplete and unsubstantiated Cargo Record Book, and an operation that did not follow the approved manual, both compounded by a crew that could not explain either. The officer assesses them against the detainable-deficiency criteria in Resolution A.1185(33). A crew unable to carry out an essential pollution-prevention operation, with records that do not support a required prewash, crosses the line.
The ship is detained. It does not sail until the deficiencies are rectified: the company demonstrates the residue was in fact landed or arranges a compliant prewash, the crew is brought up to competence on the procedures, the records are corrected, and a re-inspection confirms it. The detention is reported to the flag State, which is obliged to investigate, and it is entered in the regional database, where it raises the ship’s risk profile for its next call and counts toward its flag’s standing on the White-Grey-Black list. The recognized organization that issued the certificate sees the operational failure recorded against a ship it surveyed. Every step traces back to Regulation 16 read with Articles 5 and 6 and applied through the Procedures for Port State Control, and every step is on the record so that the detention can withstand challenge. That is the operational-control mechanism working as designed, from the targeting that put the officer on board to the feedback that follows the ship out of port.
Limitations
This article describes the enforcement mechanism, not the substantive standards it enforces. The exact discharge conditions, the prewash end points, the speeds, distances and depths, and the Cargo Record Book entry codes are set by Regulations 13 to 15 of the Annex and are covered in their own articles; where they appear here it is to show what the inspection tests, not to restate the rule. The category system that decides which cargoes attract a mandatory prewash is the subject of Regulation 6 and the Annex II hub, and is summarized here only as far as the inspection needs it.
The regulation numbering used here is the consolidated revised Annex II as adopted by Resolution MEPC.118(52) and amended since. Older documentation predating the 1 January 2007 revision uses a different numbering, and references that cite “Annex II Regulation 11” for port State control on operational requirements are applying the Annex I number to the wrong annex; the correct Annex II citation is Regulation 16, with the operational-requirements limb at paragraph 16.9. Verify the current regulation text and the current paragraph numbering against the consolidated Annex II before relying on a specific sub-paragraph reference, because the IMO renumbers and amends through the MEPC cycle.
The Procedures for Port State Control are revised on a roughly biennial Assembly cycle. The current edition is Resolution A.1185(33), 2023; an inspection always runs on the edition in force at the time, and the deficiency and detention criteria can change between editions. The Paris and Tokyo MoU figures cited, the membership counts and the campaign topics, are current to the period stated and are revised by the regimes from year to year; the annual reports of each MoU are the authoritative source for current numbers. Nothing here is a substitute for the consolidated convention text, the current Procedures, and the relevant regional MoU procedures, read together, when a real inspection or a real detention is in question.
See also
- MARPOL Annex II: control of pollution by noxious liquid substances
- MARPOL Annex II Regulation 15: Cargo Record Book
- MARPOL Annex I Regulation 11: PSC on operational requirements
- Port State control
- Paris Memorandum of Understanding
- Tokyo MoU port State control
- MARPOL Convention: the pollution-prevention treaty
- IBC Code: construction and equipment of chemical tankers
- ISM Code: safety management and crew familiarity