MARPOL Annex I Reg 36: Oil Record Book Part II

Regulation 36: the cargo-side operational logbook

Regulation 36 of MARPOL Annex I carries the heading Oil Record Book Part II: Cargo/ballast operations. It applies to every oil tanker of 150 gross tonnage and above. The rule does for the cargo and slop-tank side of a tanker what Regulation 17 does for the engine room: it turns the discharge regime into something an outside party can inspect. Without it, the operational discharge criteria for cargo-tank washings and oily ballast would describe conditions that could not be reconstructed after the fact.

The two books answer to two different operating worlds on the same hull. Machinery-space oil (fuel, lubricating oil, bilge water, oily-water-separator effluent, sludge) moves through the engine room and is logged in Part I. Cargo oil and the water that has touched it (ballast carried in cargo tanks, tank washings, slop, dirty ballast) moves through the cargo system and is logged in Part II. The dividing line is the cargo pumproom bulkhead, not the type of oil. A non-tanker of 5,000 GT carries only Part I. A 160 GT bunkering barge classed as an oil tanker carries Part II as well, because it loads and discharges oil as cargo.

The reason the 150 GT cargo-side threshold sits below the 400 GT machinery threshold is the discharge geometry. Cargo and slop volumes on a tanker dwarf bilge volumes, so the operational-discharge regime reaches smaller hulls. A small product tanker that never triggers a single Part I sludge entry on a short coastal run can move several thousand cubic meters of cargo and generate a dense Part II in the same week. The book is the only contemporaneous record that an inspector, a flag-State surveyor, or a court can use to establish what the cargo system actually did.

Part I versus Part II: the explicit distinction

The single most common confusion in tanker compliance is which book takes which entry, so the boundary is worth drawing precisely. The two books are not duplicates and they are not interchangeable. They overlap at exactly one seam, and that seam is itself a recorded operation.

Part I under Regulation 17 covers machinery-space operations on every ship of 400 GT and above: bunkering of fuel and lubricating oil, internal transfer of fuel oil, operation of the oily-water separator and discharge of its effluent, disposal of oil residue (sludge), and discharge of bilge water that has accumulated in machinery spaces. Its entry codes run A through I in the form revised by Resolution MEPC.314(74), which entered into force on 1 October 2020.

Part II under Regulation 36 covers cargo and ballast operations on every oil tanker of 150 GT and above: loading, internal transfer, and unloading of oil cargo; crude oil washing; ballasting and cleaning of cargo tanks and dedicated clean ballast tanks; discharge of dirty ballast; discharge of water from slop tanks; collection and disposal of residues and oily mixtures; discharge of clean ballast; and the condition of the oil discharge monitoring and control system. Its entry codes run A through O in the Appendix III form as revised by Resolution MEPC.187(59).

On most tankers the chief officer maintains Part II and the chief engineer maintains Part I, because the cargo system is the deck department’s responsibility and the machinery system is the engine department’s. The split matters when an operation crosses the boundary. If slop or tank washings are pumped to a settling tank and the recovered oil is later used as fuel, or if bilge water from the cargo pumproom is handled, the operation appears once in the correct book, and a Port State Control officer will trace the cross-reference between the two. The books are inspected together precisely because the boundary is a place where a falsifier can try to make oil disappear from one ledger without it appearing in the other.

The Appendix III Part II code-letter scheme: A through O

The operations subject to Part II are listed as lettered items in the List of items to be recorded in Appendix III to MARPOL Annex I. Each lettered item carries its own set of numbered data fields, and an entry cites the code letter and the item numbers that apply. The canonical sequence runs A through O, fifteen codes, in the form revised by Resolution MEPC.187(59) and reproduced in government implementations such as the US Coast Guard form at 33 CFR 151.25 and the Australian Maritime Safety Authority form AMSA 229.

The lettering in the Appendix III form is fixed worldwide; the printed national forms reproduce the same A-to-O sequence. The two items that practitioners most often log incorrectly are the slop-tank decant under (I) and the residue handling under (J). The regulation treats the collection, transfer, and disposal of oily residues and mixtures not otherwise dealt with as a recorded event in its own right under (J). An officer who logs the slop-tank discharge under (I) but leaves no matching residue entry under (J) has produced an incomplete sequence that an inspector reads as a hanging operation. The condition of the oil discharge monitoring and control system is itself a recorded item under (M), so a monitor failure during a voyage is documented in the book rather than left to inference.

What each entry must carry

Across every code, the entry carries the same skeleton of fields: the date of the operation; the code letter and the item numbers; the place or coordinates; the quantity in cubic meters with units kept consistent throughout the single book; the signature of the officer in charge of that operation; and the master’s countersignature on the completed page. The variable content sits in the operation-specific item numbers in the table above.

The place field is exact. For loading, internal transfer, and unloading it is the terminal name or berth. For an overboard discharge, code (H) or (I), it is the position where the discharge began and the position where it ended, both in latitude and longitude to one minute or finer, because the discharge criteria under the operational regime depend on the ship’s position relative to land and to a special area. For crude oil washing carried out between two discharge ports, item (D) records the ship’s position rather than a port name.

The quantity field is in cubic meters and is meant to reconcile against tank ullages. A code (A) load of 95,000 cubic meters reconciles against the sum of the ullaged tank volumes and against the cargo documents from the loading terminal. A code (I) slop-tank discharge of 40 cubic meters reconciles against the ullage drop in the slop tank and against the volume that the oil discharge monitoring and control system metered overboard. Quantity is where the arithmetic check lives, so it is the field a falsifier is most tempted to round, and the field an auditor reads first.

ODMCS reconciliation: the cargo-side magic pipe

The cargo equivalent of the engine-room magic pipe is an overboard discharge from a cargo or slop tank that is either unrecorded in Part II or recorded outside the conditions the operational discharge regime allows. The instrument that makes the discharge auditable is the oil discharge monitoring and control system, the ODMCS required on oil tankers of 150 GT and above. The system meters the instantaneous rate of oil discharge, the oil content of the effluent in parts per million, and the ship’s position and speed, and it produces a continuous record. That record sits beside Part II as the independent witness to every code (H) and code (I) overboard operation.

A Port State Control officer runs the cargo-side reconciliation as a fixed set of cross-checks, the cargo analogue of the bilge-water checks described in the Regulation 17 article. The starting point is that the figures across the documents should agree on a clean ship and disagree on a ship with a problem.

The ODMCS record check compares the continuous monitor printout against the code (H) and code (I) entries. Every overboard slop or dirty-ballast discharge logged in Part II should have a matching monitor trace showing the same start time, the same start & finish positions, the same quantity, and an oil content profile that stayed within the operational limit. A code (I) entry with no monitor trace behind it is the cargo-side magic-pipe signature: a discharge that the book admits happened but the instrument never saw, which means it bypassed the metering point. The reverse, a monitor trace with no Part II entry, points to an operation the crew tried to keep off the ledger.

The discharge-conditions check reads the code (H) and code (I) entries against the operational discharge criteria. A slop-tank discharge is lawful only when the tanker is en route, more than 50 nautical miles from the nearest land, the instantaneous rate of discharge does not exceed 30 liters per nautical mile, the total quantity for the voyage stays within the limit tied to cargo carried, and the ODMCS is running. The 50-mile, 30-liter, and total-quantity limits are the operational discharge controls that sit in the discharge-control regime alongside Regulation 15 discharge control. An (I) entry whose position field places the discharge inside 50 miles of land, or inside a special area where the operational regime is stricter, is a discharge logged outside the conditions the regime allows. That is the documentary equivalent of catching the bypass: the crew recorded the operation honestly but recorded it at a position or a rate the rules forbid.

The GPS track and deck-log cross-reference is the third leg. The position written in the code (H) or code (I) entry is checked against the voyage data recorder track, the GPS log, and the deck logbook for the same timestamp. A discharge position that does not match where the ship actually was, at the speed the deck log records for that hour, is a documentary inconsistency that no amount of tidy handwriting can repair. EU coastal states run the same check at fleet scale through satellite slick detection: an oil slick detected from space is correlated with the AIS track of every candidate vessel, and the candidate’s Part II is requested at the next port call. A slick that the ship’s own Part II cannot explain triggers a formal investigation.

The cargo and ullage reconciliation closes the loop on the volume side. The code (A) loading quantities, the code (C) unloading quantities, the slop generated, and the slop discharged should balance against the ullage record and the cargo documents from the load & discharge terminals. A tanker that loaded a recorded volume, discharged a recorded volume, and shows a slop inventory that cannot account for the difference has either an arithmetic error or an unrecorded overboard operation. The ullage record is the physical measurement; Part II is the narrative; the cargo documents are the third-party paper. When the three disagree, the inspector pulls the thread.

A clean Part II on a clean tanker passes every one of these checks without effort. A tanker running a cargo-side bypass fails at least one, because the bypass produces a discharge that the instrument did not meter, the position cannot justify, or the volume cannot account for.

Crude oil washing, load-on-top, and slop-tank decanting

Three tanker operations generate the densest and most scrutinized Part II entries, and they interlock. Each leaves a distinct signature in the book, and the way the signatures fit together is itself a compliance check.

Crude oil washing is logged under code (D). The entry records the tank washed, the number of tank-washing machines run, the start & finish times, the washing method (top, bottom, single-stage, multi-stage), the quantity of crude oil used as the washing medium, and the inert-gas condition during the wash. The inert-gas field matters because crude oil washing is permitted only with the cargo tank atmosphere kept below the flammable range, so a code (D) entry that omits or contradicts the inert-gas status is both a safety flag and a compliance flag. Crude oil washing is the operation that lets a crude carrier clean cargo tanks with the cargo itself rather than with seawater, which is the mechanism that removes the need for the dirty-ballast and tank-washing discharges that the old practice generated. A VLCC discharging in Asia after loading in the Arabian Gulf will show a run of code (D) entries through the discharge-port stay, one per tank washed, each cross-referenced to the ship’s crude oil washing operations and equipment manual.

Load-on-top is the operating philosophy that the entire Part II discharge regime was built to make auditable. Rather than pump dirty ballast and tank washings straight overboard, the tanker collects them in a slop tank, lets the oil & water separate by gravity during the ballast voyage, decants the clean water layer overboard under the operational discharge criteria, and loads the next cargo on top of the retained oil layer. The retained oil becomes part of the next cargo. The signature of load-on-top in Part II is a sequence: code (G) tank-cleaning entries transferring washings to the slop tank, code (E) or code (H) ballast entries, a settling period, then a code (I) slop-tank discharge of the separated water, and finally a code (A) loading entry that takes the next cargo on top of the retained slop. The sequence has to hang together. A code (I) slop discharge with no preceding code (G) tank-cleaning entries to fill the slop tank is a discharge of water the book never accounted for collecting.

Slop-tank decanting is the code (I) operation at the heart of load-on-top, and it is the single most sensitive entry in the book. The decant is the deliberate overboard discharge of the separated water layer after settling. It is lawful only inside the operational discharge window: more than 50 nautical miles from land, en route, within the rate & total-quantity limits, with the ODMCS running and the oil-water interface monitored so that the decant stops before it reaches the oil layer. The code (I) entry records the settling time or position, the discharge start & finish positions, the quantity, the rate, the oil content the monitor read, and the quantity of oily residue retained on board. The handling of that retained oily residue, where it went and how, is recorded under code (J) as the collection, transfer, and disposal of residues and oily mixtures. The decant under (I), the residue disposition under (J), and the condition of the monitor under (M) are read as a unit. A decant that stops at the right interface leaves a clean monitor trace and a sensible retained-residue figure. A decant that ran into the oil layer shows up as a rising oil-content tail on the monitor record that the code (I) entry would have to either disclose or hide.

Falsification as a stand-alone offense

The hardest lesson from oil-pollution enforcement is that the recording offense is prosecuted more severely than the discharge it conceals, and Part II carries the same exposure as Part I. An honest book that records an operational difficulty is defensible. A falsified book is not, and the falsification is a separate crime from the discharge whether or not the underlying discharge was lawful.

In the United States the Act to Prevent Pollution from Ships sits at 33 USC 1908. Section 1908(a) makes a knowing violation of MARPOL or APPS a criminal offense, charged as a Class D felony with a maximum of six years imprisonment per count, with fines set under the general criminal-fine statute. The decisive feature for record-book cases is that each false entry is a separate count, so a Part II with multiple falsified code (I) or code (H) entries supports multiple counts and a multiplied maximum penalty. The jurisdictional hook is that the offense of presenting a false Oil Record Book is committed where the book is presented. A foreign-flag tanker that discharged in international waters cannot ordinarily be prosecuted in a US court for that discharge, but the moment its master hands a false Part II to a Coast Guard boarding officer in a US port, a US-soil offense has occurred, and the US courts have jurisdiction over the foreign-flag ship and its crew. The appellate holding behind that reach is United States v. Jho, decided by the Fifth Circuit in 2008, which confirmed that the failure to maintain an accurate Oil Record Book is an offense completed in US waters when the inaccurate book is produced there.

The same logic that built the Part I magic-pipe prosecutions applies to the cargo side. The discharge is often the easy crime; the failure to record it, or the entry that records it falsely, is the felony. The cargo-side analogue of the engine-room bypass is the slop-tank discharge that the ODMCS never metered or the code (I) entry that places a real discharge at a fictitious position outside the conditions the regime allowed. APPS also carries a whistleblower provision under which a court may award up to half the criminal fine to a person whose information led to conviction, which is the practical engine behind detection: routine inspection finds few bypasses, but a crew member’s report finds many.

Outside the United States the European framework runs in parallel. Directive 2005/35/EC on ship-source pollution, amended by Directive 2009/123/EC, makes a discharge in breach of MARPOL a criminal offense across the European Economic Area and treats the Oil Record Book as admissible evidence, with falsification prosecuted under national law. The penalty levels are set by each member state, so the exposure is a patchwork rather than a single figure, but the principle is the same: the book is evidence, and a false book is a crime.

Retention, signatures, and the without-delay rule

Regulation 36 fixes the retention period for a completed Oil Record Book Part II at three years from the date of the last entry, with the book kept on board and readily available for inspection throughout that period. The practical consequence on a working tanker is that two or three filled Part II books are usually on board at any time: the current book, its immediate predecessor, and sometimes a second predecessor that has not yet reached the end of its three-year window. A Port State Control officer asks to see every book currently on board, and the consistency between books across the boundary date is itself an inspection target, because a discontinuity at the seam between two books is a place to hide an operation.

Each completed operation is signed and dated by the officer in charge of that operation, and each completed page is countersigned by the master of the ship. The officer’s signature is a legal attestation that the entry is true and complete; the master’s countersignature is the binding statement on the truth of the page. The master’s certification is the operative document when falsification is alleged, because it puts the master’s name on the accuracy of every line on the page. On most tankers the chief officer signs the routine cargo and ballast entries as the officer in charge, and the master countersigns the completed page.

Entries are made without delay. Most flag administrations read that as same-watch, and certainly same-day. Late entries, retroactive entries, gaps in the page sequence, and corrections that are not made cleanly are read as red flags in any inspection. The correction rule is mechanical: an erroneous entry is struck through with a single line so the original remains legible, initialed by the correcting officer, and the correct entry written alongside. Nothing is erased or overwritten. Entries are written in English, French, or Spanish, and a flag State may add a national-language version. The same three-year retention and tamper-evidence requirements apply where a flag State has authorized an electronic Oil Record Book, with the system required to produce a record that an inspector can export without dependence on company servers.

Worked reconciliation: a slop-tank decant on a ballast voyage

A concrete sequence shows how the checks fit together. Take a 105,000 DWT crude carrier that has just finished discharging in Asia and is starting the ballast leg back to the load port. During the discharge the crew ran crude oil washing on the cargo tanks, which is logged as a run of code (D) entries, one per tank, each recording the tank, the number of machines, the start & finish times, and the inert-gas condition kept positive throughout. No seawater touched the cargo tanks during cleaning, so there are no code (G) tank-washing entries generating washings to the slop tank from this discharge.

For the ballast voyage the crew loads departure ballast into the segregated ballast tanks, which never enter the cargo system, so those operations generate no Part II discharge entries at all on a properly segregated tanker. The cargo tanks carry a small heel of crude and washings that has collected in the designated slop tank. The slop tank ullage at the start of the voyage corresponds to 220 cubic meters of mixed oil and water.

Three days out, well clear of land, the master decides to decant the separated water. The settling time is logged, and the code (I) entry opens. The discharge begins at a position more than 50 nautical miles from the nearest land, with the tanker en route at 12 knots and the ODMCS running. The crew monitors the oil-water interface and the monitor’s oil-content reading, and stops the decant when the interface approaches the discharge line. The code (I) entry records the start position, the finish position, a discharged quantity of 150 cubic meters, an instantaneous rate that stayed below the operational limit, the oil-content trace the monitor produced, and a retained oily residue of 70 cubic meters. The disposition of that 70 cubic meters of retained residue, held on board for the next cargo under load-on-top, is then recorded under code (J), with the tank identity and quantity carried forward.

The reconciliation is now arithmetic. The slop tank held 220 cubic meters. The decant removed 150 cubic meters. The retained residue is 70 cubic meters. The figures close: 220 minus 150 equals 70. The ODMCS printout shows a single discharge event at the same start time, the same start and finish positions, the same 150 cubic meter quantity, and an oil-content profile that stayed inside the limit and rose only at the very end before the decant stopped. The GPS track and deck log put the ship at the recorded position at the recorded time, en route at the recorded speed, more than 50 miles from land. Every check agrees. This is what a clean cargo-side discharge looks like in the record.

Now change one number to see the failure mode. Suppose the same code (I) entry records the discharge but the ODMCS printout shows no event at that timestamp, or shows an event of a different quantity at a different position. The book says 150 cubic meters went overboard under monitor control; the instrument never metered it. That gap is the cargo-side magic-pipe signature, and it does not depend on the inspector catching anyone in the act. The two records were supposed to be made by independent systems, one by hand and one automatically, and they do not match. The retained-residue arithmetic might still close on paper, but the missing monitor trace is the documentary fact that opens the investigation. The discharge may even have been physically lawful in rate and position; the offense, if the entry was made knowing the monitor record contradicts it, is the false entry.

The IOPP verification chain

The International Oil Pollution Prevention certificate is the document that certifies a tanker’s Annex I systems, and Part II is one of the primary evidentiary records the surveyor reviews at each renewal survey. The certificate is renewed at five-year intervals, and the renewal survey confirms that the ship has operated in accordance with the certificate’s Form B supplement, which describes the tanker’s cargo, slop, crude oil washing, & ballast arrangements. Part II is the only contemporaneous record of how those arrangements were actually used across the five-year cycle.

The surveyor applies the same consistency tests a Port State Control officer applies, with the added dimension of reviewing the trend across years. A tanker whose code (I) slop-tank discharges cluster in particular voyage segments, or whose crude oil washing entries do not match its trading pattern, draws scrutiny. The findings are recorded in the renewal-survey report filed with the flag-State administration and are available if a later inspection produces a similar finding. The chain runs from the daily entry, through the master’s countersignature, through the Port State Control check, to the five-yearly survey, and any break in that chain is where an investigation starts.

Origins: from OILPOL to the load-on-top record

The cargo-side oil record predates MARPOL. The 1954 International Convention for the Prevention of Pollution of the Sea by Oil, OILPOL 1954, introduced an oil record book for tankers and required entries for ballasting, tank cleaning, and the discharge of oily residues. The early regime allowed operational discharge under loose conditions and relied on the book as the only proof that a tanker had handled its slops within them. The book existed before the instruments that now verify it, so for two decades the record was effectively self-certified.

MARPOL 73/78 rebuilt the regime around two changes that gave Part II its present shape. The first was the operational discharge criteria tied to distance from land, rate, & total quantity, which turned a vague duty into testable numbers. The second was the oil discharge monitoring and control system, which gave the code (I) slop-tank entry an independent witness. The structural separation into Part I for machinery spaces and Part II for cargo and ballast operations dates from this rebuild, which is why a tanker carries two books while a bulk carrier carries one.

The slop-tank and clean-ballast architecture the book records reflects a sequence of equipment requirements layered onto the fleet over the 1970s and 1980s. Crude oil washing under Regulation 33 removed the need for seawater tank cleaning on crude carriers, which cut the dirty-ballast & tank-washing discharges that filled the older books. Segregated ballast tanks under Regulation 18 removed ballast water from the cargo system entirely on the ships fitted with them. Dedicated clean ballast tanks were the interim arrangement on some ships, and they are the reason codes (F) and (L) exist: ballasting a dedicated clean ballast tank under (F) and later discharging that ballast under (L) is a recorded pair of operations confined to CBT tankers. As the fleet moved to full segregation, the dirty-ballast entries under code (H) became the exception rather than the rule, and a modern segregated tanker’s Part II is dominated by loading, unloading, and crude oil washing rather than by overboard ballast discharges.

The form itself has been revised to match enforcement experience. The A-to-O Part II form in current use is the one set by Resolution MEPC.187(59), adopted 17 July 2009 and in force 1 January 2011, which revised both the Oil Record Book Part I and Part II forms in Appendix III. The lettered list in Appendix III has been refined across MARPOL amendments, and flag administrations have issued the consolidated form with the item-number fields that make the cross-references machine-checkable. The direction of every revision has been the same: more position fields, more quantity fields, & tighter signature requirements, because the gaps that falsifiers exploited were the fields the older forms left optional.

Where to find each input

The values that go into a Part II entry come from specific documents and instruments, and knowing the source of each is half of completing the book correctly. The loading and unloading quantities under codes (A) and (C) come from the cargo documents & the ullage report agreed with the terminal. The ballast quantities under codes (E), (F), and (H) come from the tank gauging system & the cargo plan. The crude oil washing data under code (D) comes from the crude oil washing operations and equipment manual and the tank-washing log. The discharge positions under codes (H) and (I) come from the GPS and the bridge position log, timed to the discharge. The oil-content readings and the metered quantity under code (I) come from the ODMCS printout. The retained-residue figures under codes (I) and (J) come from the slop-tank ullage. An entry whose fields trace cleanly back to these sources will survive reconciliation; an entry whose figures cannot be sourced is the one that fails.

Common errors in Part II entries

A set of clerical failures recurs in Part II audits that, taken alone, are not falsification but are the threads an inspector pulls. Mixing units within a single book, cubic meters in one entry and tonnes in another, breaks every volume reconciliation and is the most common finding. A missing master countersignature on a completed page voids the page’s evidentiary weight. A code (I) slop-tank discharge with no following code (J) residue-handling entry, where the retained oily residue went unaccounted, leaves a hanging operation. A discharge position written to a coarser precision than one minute of latitude and longitude defeats the GPS cross-reference. A correction made by erasure or overwriting rather than by a struck-through single line invites the question of what the original said. A code (D) crude oil washing entry that omits the inert-gas condition raises both a safety and a compliance flag. None of these on its own proves an offense, but each is a reason to look harder.

Limitations

The Oil Record Book Part II is a procedural document, and the consistency checks built on it are screening tools, not proof of compliance. They have known blind spots that a practitioner has to keep in view.

The ODMCS reconciliation fails where the monitor itself is defeated. A discharge routed around the metering point, or a monitor fed a clean-water sample while oily water goes overboard elsewhere, produces a clean trace that the book can match. Detection in that case depends on physical inspection of the cargo & pumproom piping for unauthorized hoses, jumpers, and bypass connections that do not appear on the approved piping diagram, not on arithmetic. The book and the monitor agree precisely because both have been bypassed.

The position cross-reference fails where the falsifier has access to the same GPS the inspector checks. An entry can be made internally consistent with the deck log & the GPS track if the whole set of documents is fabricated together, which is why coordinated falsification by a crew acting in concert is harder to detect than a single careless entry. The satellite slick-detection programs that EU coastal states run are the external check that a self-consistent set of ship’s documents cannot defeat, because the slick is observed independently of the ship’s own records.

The volume reconciliation fails on tankers with complex cargo and slop arrangements, where multiple slop tanks, segregated ballast that never enters the cargo system, and load-on-top retained oil make the mass balance harder to close. Segregated ballast tank operations on a modern tanker are designed so that ballast water never touches the cargo system, which removes most of the dirty-ballast and tank-washing discharges that the older clean-ballast-tank and load-on-top regimes generated. On such ships the Part II is thinner, and the absence of code (H) and code (I) entries is itself the expected pattern rather than a gap to explain.

Part II also says nothing about the machinery side. A cargo-tank discharge that the cargo system never touched but that passed through the engine room, such as cargo-pumproom bilge water handled through the machinery bilge system, lives in Part I, and an inspector who reads only one book will miss the cross-boundary operation. The two books have to be read together, because the seam between them is the place a falsifier tries to work.

See also

This article sits under the MARPOL Annex I oil-pollution-prevention spoke, itself a chapter of the broader MARPOL Convention.

• MARPOL Annex I Regulation 17: Oil Record Book Part I
• MARPOL Annex I Regulation 15: discharge control
• MARPOL Annex I Regulation 33: crude oil washing
• MARPOL Annex I Regulation 12: oil residue (sludge) tanks
• MARPOL Annex I Regulation 14: oil filtering equipment
• MARPOL Annex I Regulation 18: segregated ballast tanks
• MARPOL Annex I special areas
• International Oil Pollution Prevention certificate
• Port State Control
• MARPOL Annex I oil pollution prevention
• MARPOL Convention overview
• MARPOL Annex I/36 - Oil Record Book Part II calculator
• MARPOL Annex I/17 - Oil Record Book Part I calculator
• Tanker washings Oil Record Book calculator