MAJ OOW Deck Exam cheat sheet

Great-circle distance: D = 60 × arccos(sin φ1 sin φ2 + cos φ1 cos φ2 cos Δλ), result in nautical miles.

Mercator sailing: departure = DLo × cos (mean or mid latitude); use mid-latitude method only when DLo < 600' and latitude change is small.

Plane sailing: departure = DLat × tan course; run the calculation only for short legs (under about 600 miles).

Azimuth of a body: Az = arctan(sin LHA / (cos Lat × tan Dec − sin Lat × cos LHA)), quadrant resolved from LHA and assumed position.

Sextant altitude corrections sequence: index error, dip (negative), refraction, semi-diameter (add for lower limb), parallax; then Ho = Hs + IC − dip ± SD − refraction + parallax.

Observed position by two or three position lines: plot intercepts (Toward/Away) along the azimuths from the assumed position; the cocked hat radius equals the fix uncertainty.

GPS position accuracy: typical horizontal 3–5 m with SBAS; RAIM must be available for the approach and harbour phase, and the receiver must flag a RAIM warning.

Tidal height at a standard port: height = MHWS − (range × factor) using the rule-of-twelfths for the interval after HW/LW; interpolate for non-standard ports using the difference tables.

Rule 13: any vessel overtaking another keeps clear until finally past and clear, regardless of what the overtaken vessel is doing.

Rule 14 head-on: both vessels alter course to starboard and pass port-to-port; no requirement for sound signal in sight of one another but the manoeuvre must be substantial.

Rule 15 crossing: the vessel with the other on her own starboard side is give-way; if risk of collision exists, take early and substantial action to keep well clear.

Rule 19 restricted visibility: reduce to safe speed, no assumed right of way, and if risk of collision exists take avoiding action in ample time; avoid altering course to port for a vessel forward of the beam (except overtaking).

Rule 10 traffic separation: vessels in a lane proceed in the general direction of traffic flow; crossing should be at right angles, and inshore traffic zones are for local traffic, not normal through passage.

Rule 5 and Rule 6: proper lookout by sight, hearing and all available means, and safe speed determined by visibility, traffic density, manoeuvrability, background light and state of wind/sea.

Rule 34 and 35 sound signals: one short = altering to starboard, two short = to port, three short = operating astern propulsion; in fog, one prolonged blast every 2 minutes for a power-driven vessel making way.

Narrow channel Rule 9: keep close to the outer limit on your starboard side; a vessel under 20 m or a sailing vessel must not impede a vessel that can only navigate within the channel.

Buys Ballot's law: in the Northern Hemisphere, with your back to the wind, low pressure lies to your left; reverse in the Southern Hemisphere.

Beaufort wind force is derived from observed sea state, not from instrument readings alone; force 8 = gale, force 10 = storm, force 12 = hurricane.

Tropical revolving storm: minimum safe distance from the track is 200–250 nm; in the Northern Hemisphere, manoeuvre to put the wind on the starboard bow (right-hand semicircle) to run away from the centre.

Fog formation: radiation fog forms over land on clear calm nights; advection fog forms when warm moist air moves over a cold surface and requires wind to form.

Swell is generated by distant weather systems and can propagate thousands of miles; the swell direction indicates the bearing of the generating depression.

Semi-diurnal tide: two high waters and two low waters per tidal day (~24 h 50 min), with the tidal day 50 minutes longer than the solar day.

Sea breeze: blows from sea to land by day due to differential heating; land breeze reverses at night; both are diurnal and local, not synoptic.

Frontal passage: a cold front brings a sharp wind veer, temperature drop, pressure rise and squally showers; a warm front brings a gradual veer, rising temperature and steady rain.

Load line marks: S = summer, W = winter, T = tropical, F = fresh water, TF = tropical fresh; distances between marks are set by the assigning classification society.

Freeboard deck is the uppermost continuous deck with permanent means of closing all openings; the load line is measured from this deck.

Double bottom height is typically 0.76–1.2 m; it provides longitudinal strength, grounding protection and tank capacity.

Collision bulkhead: located at least 5% of LOA or 3 m (whichever is greater) from the forward perpendicular, and not more than 8% of LOA.

Bilge keel reduces roll amplitude but adds little to stability; it is fitted at the turn of the bilge and extends over the midship region.

Cofferdam: a void space between two bulkheads or tanks that prevents contamination or leakage between them; typically 0.6–1.2 m wide.

Hatch covers: steel hatch covers must be weathertight and secured by cleats; the number and spacing of cleats and the compression bar are specified in the load line convention.

Panting arrangements: panting stringers, beams and wash bulkheads in the fore and aft peaks resist the fluctuating pressure from pitching in a seaway.

GM = KM − KG; positive GM = stable, negative GM = unstable; GM of 0.15–0.30 m is typical for a loaded general cargo ship.

GZ curve: area under the curve to 30° must be at least 0.055 m·rad, to 40° at least 0.09 m·rad, and between 30° and 40° at least 0.03 m·rad (IS Code 2008).

Maximum GZ must occur at an angle of at least 25°, and the angle of vanishing stability must be at least 60° for most cargo ships.

Free surface effect: FSC = i × ρ / (Δ), where i is the second moment of area of the free surface; the effective GM is reduced by the FSC.

Trim: change of trim = (w × d) / MCTC, where w is the mass moved, d the distance moved, and MCTC is the moment to change trim by 1 cm.

Angle of loll: a vessel with negative GM will list to either side; correct by lowering weights or filling low tanks, never by shifting weight to the high side.

Deadweight = displacement − lightship; it includes cargo, bunkers, fresh water, ballast, stores and crew.

Block coefficient Cb = Δ / (L × B × d × ρ); typical values are 0.6–0.7 for general cargo and 0.8–0.85 for tankers and bulkers.

Hague-Visby Rules: carrier must exercise due diligence to make the ship seaworthy and properly man, equip and supply her before and at the beginning of the voyage.

Hague-Visby package limitation: 666.67 SDR per package or 2 SDR per kg, whichever is higher, unless the nature and value have been declared.

Bill of lading: a receipt for goods shipped, evidence of the contract of carriage, and a document of title; a clean B/L bears no adverse remarks about the goods.

Cargo sweat and ship sweat: cargo sweat forms when warm moist air meets a cold cargo; ventilate only when the dew point of outside air is lower than the cargo dew point.

Bulk carrier: cargo density and angle of repose determine the stowage factor; high-density cargoes such as iron ore require alternate hold loading or reduced loading rates.

Dangerous goods: IMDG Code class 1 explosives, class 2 gases, class 3 flammable liquids, class 4 flammable solids, class 5 oxidizers, class 6 toxic, class 7 radioactive, class 8 corrosive, class 9 miscellaneous.

Draft survey: displacement is obtained from the hydrostatic tables at the mean of forward, aft and midship drafts, corrected for trim and density.

Charter party laytime: demurrage is payable when loading or discharging exceeds laytime; despatch is paid at half demurrage for time saved.

Two-stroke slow-speed diesel: uniflow scavenging, exhaust valve in the cylinder head, and a crosshead that separates the crankcase from the combustion space.

Four-stroke medium-speed engine: trunk piston, inlet and exhaust valves in the head, and a separate lubricating oil system for the crankcase and cylinder liners.

Fuel oil treatment: settling tank, purifier and clarifier in series; viscosity is controlled to 10–15 cSt at the injector by a viscosimeter and heater.

Boiler feedwater: chemical dosing controls alkalinity (pH 10–11) and phosphate; dissolved oxygen is removed by a deaerator and hydrazine or sulphite.

Pump types: centrifugal for large volumes at low head (ballast, cooling water); positive displacement (reciprocating, screw, gear) for high pressure or viscous fluids.

Steering gear: SOLAS requires two independent power units, and the main steering gear must be capable of putting the rudder over from 35° on one side to 35° on the other in 28 seconds at maximum ahead service speed.

Emergency generator: must start and take load within 45 seconds of a blackout, and be capable of supplying emergency lighting, navigation lights and radio for at least 18 hours (30 hours for some ships).

Maintenance planning: PMS (planned maintenance system) records are subject to classification society and PSC inspection; critical items include steering gear, emergency fire pump and lifeboat engines.

Muster list: every person on board must be assigned a duty; the list is displayed in conspicuous places including the bridge, engine room and accommodation.

Abandon ship: the decision rests with the master; the order is given by seven short blasts and one prolonged blast on the ship's whistle.

Man overboard: immediate helm to swing the stern away from the person, release the MOB marker, sound three long blasts, and commence a Williamson or Anderson turn.

Fire in port: notify the terminal and shore fire brigade, close all openings, and use the ship's fixed system only after all personnel are accounted for.

Collision: sound the general alarm, close watertight doors, muster and check for injuries, then exchange ship's particulars with the other vessel and report to the nearest coastal state.

Grounding: sound the general alarm, stop the engines, take soundings around the vessel, and check for flooding before attempting to refloat.

Emergency radio: DSC alert on VHF channel 70 followed by Mayday on channel 16; MF/HF DSC on 2187.5 kHz and subsequent radiotelephony on 2182 kHz.

SAR coordination: the on-scene coordinator is normally the first vessel to arrive; the SAR mission coordinator is ashore at the rescue coordination centre.

Fire triangle: fuel, oxygen and heat; extinguishing methods are starvation, smothering, cooling and chemical inhibition.

Fire classes: A = solid combustibles (water), B = flammable liquids (foam, CO2, dry powder), C = gases (dry powder, shut off supply), D = metals (special dry powder), F = cooking oils (wet chemical).

CO2 fixed system: released by two-stage alarm and delay; the space must be sealed and all personnel accounted for before release.

Fire main: pressure at any hydrant must be at least 0.27 N/mm² (2.7 bar) for cargo ships and 0.35 N/mm² for passenger ships; hydrant spacing per SOLAS II-2.

Lifebuoy: at least 8 on a cargo ship under 100 m, 12 for 100–150 m, 14 for 150–200 m and 16 for over 200 m; at least half fitted with self-igniting lights.

Lifejackets: one per person plus additional for watchkeepers and remote locations; each must be fitted with a whistle and retro-reflective tape.

Immersion suit: required for every person on board; it must allow the wearer to climb a vertical ladder and jump from at least 4.5 m without injury.

Fire drill: must be conducted at least monthly on cargo ships; the drill must include checking firefighting equipment, closing watertight and fire doors, and testing the emergency fire pump.

SOLAS: Chapter I general, II-1 construction, II-2 fire, III life-saving, IV radio, V safety of navigation, VI cargo, VII dangerous goods, IX ISM, XI-1/XI-2 special measures and ISPS.

MARPOL: Annex I oil, II noxious liquid, III harmful substances in packaged form, IV sewage, V garbage, VI air pollution.

STCW: sets minimum standards for watchkeeping, certification and rest hours; the 2010 Manila Amendments require 10 hours rest in 24 and 77 hours rest in 7 days.

UNCLOS: territorial sea 12 nm, contiguous zone 24 nm, exclusive economic zone 200 nm, and the high seas beyond.

ISPS Code: security levels 1 (normal), 2 (heightened) and 3 (exceptional); the Ship Security Plan and Ship Security Officer are mandatory.

MLC 2006: minimum age 16 (18 for night work), hours of work and rest, accommodation, food and medical care standards.

Bill of lading functions: receipt, evidence of contract, and document of title; the carrier's liability is governed by the Hague-Visby or Hamburg Rules as incorporated.

Salvage: Article 13 of the Salvage Convention 1989 sets the reward by reference to the salved value, skill and efforts, danger, time and expenses, and success.

STCW rest hours: minimum 10 hours rest in any 24-hour period and 77 hours in any 7-day period; rest may be divided into no more than two periods, one of at least 6 hours.

Bridge watch composition: a sole lookout is permitted only in daylight with good visibility and no close hazards; the OOW must not leave the bridge unattended.

Passage plan: appraisal, planning, execution and monitoring; the plan must be approved by the master and include no-go areas, abort points and contingency anchorages.

Position fixing interval: at least every 30 minutes in coastal waters, every 15 minutes in restricted waters, and continuous in pilotage waters; fix by more than one method where possible.

GMDSS: Sea Area A1 covered by VHF DSC, A2 by MF, A3 by HF or Inmarsat, A4 by HF; the ship must carry the appropriate equipment for its area.

Bridge checklist: pre-arrival, pre-departure, pilot boarding and anchoring checklists are recorded in the bridge diary and signed by the OOW.

Helm orders: standard telegraph and helm orders; the reply repeats the order, and the OOW confirms the rudder angle on the indicator before reporting.

Handover: the relieving OOW must be given the ship's position, course, speed, traffic, weather, machinery status and any standing orders before taking over.

MARPOL Annex I: any discharge of oil or oily mixture is prohibited within 50 nm of land; outside that, discharge is permitted at a rate not exceeding 30 litres per nautical mile and with an oil content below 15 ppm.

Oil Record Book Part I: machinery space operations; Part II: cargo and ballast operations on tankers; entries must be signed by the officer in charge and the master.

Garbage: Annex V prohibits discharge of all plastics; food waste may be discharged 12 nm from land (comminuted, 3 nm); cargo residues and cleaning agents have specific rules.

Sewage: Annex IV permits discharge of comminuted and disinfected sewage 3 nm from land, untreated sewage 12 nm, and requires a sewage treatment plant or holding tank.

Air pollution Annex VI: sulphur limit 0.50% m/m global from 1 January 2020, 0.10% in ECAs; NOx Tier III applies in NOx ECAs for new engines.

Ballast water: BWM Convention requires a Ballast Water Management Plan, a Ballast Water Record Book, and treatment to the D-2 standard by the compliance date.

Oil spill response: SOPEP on board every ship over 400 GT; the plan lists coastal state contacts, response equipment and the reporting procedure.

Anti-fouling: AFS Convention 2001 prohibits organotin compounds; a valid International Anti-Fouling System Certificate is required.

Great-circle distance: D = 60 × arccos(sin φ1 sin φ2 + cos φ1 cos φ2 cos Δλ), result in nautical miles.

Mercator sailing: departure = DLo × cos (mean or mid latitude); use mid-latitude method only when DLo < 600' and latitude change is small.

Plane sailing: departure = DLat × tan course; run the calculation only for short legs (under about 600 miles).

Azimuth of a body: Az = arctan(sin LHA / (cos Lat × tan Dec − sin Lat × cos LHA)), quadrant resolved from LHA and assumed position.

Sextant altitude corrections sequence: index error, dip (negative), refraction, semi-diameter (add for lower limb), parallax; then Ho = Hs + IC − dip ± SD − refraction + parallax.

Observed position by two or three position lines: plot intercepts (Toward/Away) along the azimuths from the assumed position; the cocked hat radius equals the fix uncertainty.

GPS position accuracy: typical horizontal 3–5 m with SBAS; RAIM must be available for the approach and harbour phase, and the receiver must flag a RAIM warning.

Tidal height at a standard port: height = MHWS − (range × factor) using the rule-of-twelfths for the interval after HW/LW; interpolate for non-standard ports using the difference tables.

Rule 13: any vessel overtaking another keeps clear until finally past and clear, regardless of what the overtaken vessel is doing.

Rule 14 head-on: both vessels alter course to starboard and pass port-to-port; no requirement for sound signal in sight of one another but the manoeuvre must be substantial.

Rule 15 crossing: the vessel with the other on her own starboard side is give-way; if risk of collision exists, take early and substantial action to keep well clear.

Rule 19 restricted visibility: reduce to safe speed, no assumed right of way, and if risk of collision exists take avoiding action in ample time; avoid altering course to port for a vessel forward of the beam (except overtaking).

Rule 10 traffic separation: vessels in a lane proceed in the general direction of traffic flow; crossing should be at right angles, and inshore traffic zones are for local traffic, not normal through passage.

Rule 5 and Rule 6: proper lookout by sight, hearing and all available means, and safe speed determined by visibility, traffic density, manoeuvrability, background light and state of wind/sea.

Rule 34 and 35 sound signals: one short = altering to starboard, two short = to port, three short = operating astern propulsion; in fog, one prolonged blast every 2 minutes for a power-driven vessel making way.

Narrow channel Rule 9: keep close to the outer limit on your starboard side; a vessel under 20 m or a sailing vessel must not impede a vessel that can only navigate within the channel.

Buys Ballot's law: in the Northern Hemisphere, with your back to the wind, low pressure lies to your left; reverse in the Southern Hemisphere.

Beaufort wind force is derived from observed sea state, not from instrument readings alone; force 8 = gale, force 10 = storm, force 12 = hurricane.

Tropical revolving storm: minimum safe distance from the track is 200–250 nm; in the Northern Hemisphere, manoeuvre to put the wind on the starboard bow (right-hand semicircle) to run away from the centre.

Fog formation: radiation fog forms over land on clear calm nights; advection fog forms when warm moist air moves over a cold surface and requires wind to form.

Swell is generated by distant weather systems and can propagate thousands of miles; the swell direction indicates the bearing of the generating depression.

Semi-diurnal tide: two high waters and two low waters per tidal day (~24 h 50 min), with the tidal day 50 minutes longer than the solar day.

Sea breeze: blows from sea to land by day due to differential heating; land breeze reverses at night; both are diurnal and local, not synoptic.

Frontal passage: a cold front brings a sharp wind veer, temperature drop, pressure rise and squally showers; a warm front brings a gradual veer, rising temperature and steady rain.

Load line marks: S = summer, W = winter, T = tropical, F = fresh water, TF = tropical fresh; distances between marks are set by the assigning classification society.

Freeboard deck is the uppermost continuous deck with permanent means of closing all openings; the load line is measured from this deck.

Double bottom height is typically 0.76–1.2 m; it provides longitudinal strength, grounding protection and tank capacity.

Collision bulkhead: located at least 5% of LOA or 3 m (whichever is greater) from the forward perpendicular, and not more than 8% of LOA.

Bilge keel reduces roll amplitude but adds little to stability; it is fitted at the turn of the bilge and extends over the midship region.

Cofferdam: a void space between two bulkheads or tanks that prevents contamination or leakage between them; typically 0.6–1.2 m wide.

Hatch covers: steel hatch covers must be weathertight and secured by cleats; the number and spacing of cleats and the compression bar are specified in the load line convention.

Panting arrangements: panting stringers, beams and wash bulkheads in the fore and aft peaks resist the fluctuating pressure from pitching in a seaway.

GM = KM − KG; positive GM = stable, negative GM = unstable; GM of 0.15–0.30 m is typical for a loaded general cargo ship.

GZ curve: area under the curve to 30° must be at least 0.055 m·rad, to 40° at least 0.09 m·rad, and between 30° and 40° at least 0.03 m·rad (IS Code 2008).

Maximum GZ must occur at an angle of at least 25°, and the angle of vanishing stability must be at least 60° for most cargo ships.

Free surface effect: FSC = i × ρ / (Δ), where i is the second moment of area of the free surface; the effective GM is reduced by the FSC.

Trim: change of trim = (w × d) / MCTC, where w is the mass moved, d the distance moved, and MCTC is the moment to change trim by 1 cm.

Angle of loll: a vessel with negative GM will list to either side; correct by lowering weights or filling low tanks, never by shifting weight to the high side.

Deadweight = displacement − lightship; it includes cargo, bunkers, fresh water, ballast, stores and crew.

Block coefficient Cb = Δ / (L × B × d × ρ); typical values are 0.6–0.7 for general cargo and 0.8–0.85 for tankers and bulkers.

Hague-Visby Rules: carrier must exercise due diligence to make the ship seaworthy and properly man, equip and supply her before and at the beginning of the voyage.

Hague-Visby package limitation: 666.67 SDR per package or 2 SDR per kg, whichever is higher, unless the nature and value have been declared.

Bill of lading: a receipt for goods shipped, evidence of the contract of carriage, and a document of title; a clean B/L bears no adverse remarks about the goods.

Cargo sweat and ship sweat: cargo sweat forms when warm moist air meets a cold cargo; ventilate only when the dew point of outside air is lower than the cargo dew point.

Bulk carrier: cargo density and angle of repose determine the stowage factor; high-density cargoes such as iron ore require alternate hold loading or reduced loading rates.

Dangerous goods: IMDG Code class 1 explosives, class 2 gases, class 3 flammable liquids, class 4 flammable solids, class 5 oxidizers, class 6 toxic, class 7 radioactive, class 8 corrosive, class 9 miscellaneous.

Draft survey: displacement is obtained from the hydrostatic tables at the mean of forward, aft and midship drafts, corrected for trim and density.

Charter party laytime: demurrage is payable when loading or discharging exceeds laytime; despatch is paid at half demurrage for time saved.

Two-stroke slow-speed diesel: uniflow scavenging, exhaust valve in the cylinder head, and a crosshead that separates the crankcase from the combustion space.

Four-stroke medium-speed engine: trunk piston, inlet and exhaust valves in the head, and a separate lubricating oil system for the crankcase and cylinder liners.

Fuel oil treatment: settling tank, purifier and clarifier in series; viscosity is controlled to 10–15 cSt at the injector by a viscosimeter and heater.

Boiler feedwater: chemical dosing controls alkalinity (pH 10–11) and phosphate; dissolved oxygen is removed by a deaerator and hydrazine or sulphite.

Pump types: centrifugal for large volumes at low head (ballast, cooling water); positive displacement (reciprocating, screw, gear) for high pressure or viscous fluids.

Steering gear: SOLAS requires two independent power units, and the main steering gear must be capable of putting the rudder over from 35° on one side to 35° on the other in 28 seconds at maximum ahead service speed.

Emergency generator: must start and take load within 45 seconds of a blackout, and be capable of supplying emergency lighting, navigation lights and radio for at least 18 hours (30 hours for some ships).

Maintenance planning: PMS (planned maintenance system) records are subject to classification society and PSC inspection; critical items include steering gear, emergency fire pump and lifeboat engines.

Muster list: every person on board must be assigned a duty; the list is displayed in conspicuous places including the bridge, engine room and accommodation.

Abandon ship: the decision rests with the master; the order is given by seven short blasts and one prolonged blast on the ship's whistle.

Man overboard: immediate helm to swing the stern away from the person, release the MOB marker, sound three long blasts, and commence a Williamson or Anderson turn.

Fire in port: notify the terminal and shore fire brigade, close all openings, and use the ship's fixed system only after all personnel are accounted for.

Collision: sound the general alarm, close watertight doors, muster and check for injuries, then exchange ship's particulars with the other vessel and report to the nearest coastal state.

Grounding: sound the general alarm, stop the engines, take soundings around the vessel, and check for flooding before attempting to refloat.

Emergency radio: DSC alert on VHF channel 70 followed by Mayday on channel 16; MF/HF DSC on 2187.5 kHz and subsequent radiotelephony on 2182 kHz.

SAR coordination: the on-scene coordinator is normally the first vessel to arrive; the SAR mission coordinator is ashore at the rescue coordination centre.

Fire triangle: fuel, oxygen and heat; extinguishing methods are starvation, smothering, cooling and chemical inhibition.

Fire classes: A = solid combustibles (water), B = flammable liquids (foam, CO2, dry powder), C = gases (dry powder, shut off supply), D = metals (special dry powder), F = cooking oils (wet chemical).

CO2 fixed system: released by two-stage alarm and delay; the space must be sealed and all personnel accounted for before release.

Fire main: pressure at any hydrant must be at least 0.27 N/mm² (2.7 bar) for cargo ships and 0.35 N/mm² for passenger ships; hydrant spacing per SOLAS II-2.

Lifebuoy: at least 8 on a cargo ship under 100 m, 12 for 100–150 m, 14 for 150–200 m and 16 for over 200 m; at least half fitted with self-igniting lights.

Lifejackets: one per person plus additional for watchkeepers and remote locations; each must be fitted with a whistle and retro-reflective tape.

Immersion suit: required for every person on board; it must allow the wearer to climb a vertical ladder and jump from at least 4.5 m without injury.

Fire drill: must be conducted at least monthly on cargo ships; the drill must include checking firefighting equipment, closing watertight and fire doors, and testing the emergency fire pump.

SOLAS: Chapter I general, II-1 construction, II-2 fire, III life-saving, IV radio, V safety of navigation, VI cargo, VII dangerous goods, IX ISM, XI-1/XI-2 special measures and ISPS.

MARPOL: Annex I oil, II noxious liquid, III harmful substances in packaged form, IV sewage, V garbage, VI air pollution.

STCW: sets minimum standards for watchkeeping, certification and rest hours; the 2010 Manila Amendments require 10 hours rest in 24 and 77 hours rest in 7 days.

UNCLOS: territorial sea 12 nm, contiguous zone 24 nm, exclusive economic zone 200 nm, and the high seas beyond.

ISPS Code: security levels 1 (normal), 2 (heightened) and 3 (exceptional); the Ship Security Plan and Ship Security Officer are mandatory.

MLC 2006: minimum age 16 (18 for night work), hours of work and rest, accommodation, food and medical care standards.

Bill of lading functions: receipt, evidence of contract, and document of title; the carrier's liability is governed by the Hague-Visby or Hamburg Rules as incorporated.

Salvage: Article 13 of the Salvage Convention 1989 sets the reward by reference to the salved value, skill and efforts, danger, time and expenses, and success.

STCW rest hours: minimum 10 hours rest in any 24-hour period and 77 hours in any 7-day period; rest may be divided into no more than two periods, one of at least 6 hours.

Bridge watch composition: a sole lookout is permitted only in daylight with good visibility and no close hazards; the OOW must not leave the bridge unattended.

Passage plan: appraisal, planning, execution and monitoring; the plan must be approved by the master and include no-go areas, abort points and contingency anchorages.

Position fixing interval: at least every 30 minutes in coastal waters, every 15 minutes in restricted waters, and continuous in pilotage waters; fix by more than one method where possible.

GMDSS: Sea Area A1 covered by VHF DSC, A2 by MF, A3 by HF or Inmarsat, A4 by HF; the ship must carry the appropriate equipment for its area.

Bridge checklist: pre-arrival, pre-departure, pilot boarding and anchoring checklists are recorded in the bridge diary and signed by the OOW.

Helm orders: standard telegraph and helm orders; the reply repeats the order, and the OOW confirms the rudder angle on the indicator before reporting.

Handover: the relieving OOW must be given the ship's position, course, speed, traffic, weather, machinery status and any standing orders before taking over.

MARPOL Annex I: any discharge of oil or oily mixture is prohibited within 50 nm of land; outside that, discharge is permitted at a rate not exceeding 30 litres per nautical mile and with an oil content below 15 ppm.

Oil Record Book Part I: machinery space operations; Part II: cargo and ballast operations on tankers; entries must be signed by the officer in charge and the master.

Garbage: Annex V prohibits discharge of all plastics; food waste may be discharged 12 nm from land (comminuted, 3 nm); cargo residues and cleaning agents have specific rules.

Sewage: Annex IV permits discharge of comminuted and disinfected sewage 3 nm from land, untreated sewage 12 nm, and requires a sewage treatment plant or holding tank.

Air pollution Annex VI: sulphur limit 0.50% m/m global from 1 January 2020, 0.10% in ECAs; NOx Tier III applies in NOx ECAs for new engines.

Ballast water: BWM Convention requires a Ballast Water Management Plan, a Ballast Water Record Book, and treatment to the D-2 standard by the compliance date.

Oil spill response: SOPEP on board every ship over 400 GT; the plan lists coastal state contacts, response equipment and the reporting procedure.

Anti-fouling: AFS Convention 2001 prohibits organotin compounds; a valid International Anti-Fouling System Certificate is required.