Pollution Prevention & Garbage — Most Asked Questions
18 questions asked about pollution prevention & garbage across the General and Fn 3 papers, heaviest first. 1 of them are must-master.
Learn the system first
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1 Nox technical file
Also asked: “nox tech file”
Answer
The NOx Technical File is the engine’s emission passport under MARPOL Annex VI: every part and setting that touches NOx, recorded and surveyable.
- It records all parameters and components that can influence NOx — liner, cylinder head, piston, connecting rod, fuel pump, valves.
- NOx forms when nitrogen and oxygen meet above about 1000°C: heavy load, bad air-fuel mixture, high scavenge-air, jacket-water or liner temperatures all push it up.
- Paired with the EIAPP certificate, it is how surveyors verify compliance — usually by the parameter-check method against the file [MARPOL Annex VI / NOx Technical Code].
- Any part change outside the file’s approved range kills compliance until re-approved and re-recorded.
Surveyor follow-up: you renew a fuel pump with a non-identical spare — what happens to the NOx file?
Full theory: MARPOL Annex VI — Air Pollution: SOx, NOx & Exhaust Gas Cleaning -
2 Master of the ship is the overall in charge of the SOPEP, along with the chief officer as subordinate in charge for implementation of SOPEP on board. SOPEP also describes the plan for the master, officer and the crew of
Also asked: “Master of the ship is the overall in charge of the SOPEP, along with the chief officer as subordinate in charge for implementation of SOPEP on board. SOPEP also describes the plan for the master, officer and the crew of the ship regarding ways to tackle various oil spill scenarios that can occur on a ship”
Answer
SOPEP runs master-down: master owns the plan, chief officer runs it, every hand knows his spill station.
- Master holds overall charge with reporting, contact and response decisions.
- Chief officer as subordinate in charge drills the crew and keeps gear and diagrams ready.
- Officers and ratings own containment, clean-up and boundary duties per the muster-style plan.
- Prove by drill records, contact currency and gear stowage — the surveyor musters the spill team.
Surveyor follow-up: spill at 0200 with the master ashore — who takes charge, and what does he do first?
Full theory: MARPOL Annex I — Prevention of Pollution by Oil -
3 Ship Energy Efficiency Management Plan is an operational measure to improve the energy efficiency of a vessel in a cost effective manner by reducing greenhouse gas emission
Answer
SEEMP cuts greenhouse gas per mile without new steel: slower steaming, weather routing, clean hulls and full stows.
- Engine power limitation and tuning trim output and consumption within EEXI and CII maths.
- Layered injection, derating and low-carbon fuels step new ships toward the 2030 target.
- Existing ships lean on power limits, tuning and retrofits where conversion never pays.
- The plan lives aboard with measures, monitoring and review — the surveyor reads fuel per mile, not promises.
Surveyor follow-up: CII sliding with a clean hull — speed, routing or cargo, and what number proves it?
Full theory: MARPOL Annex VI — Emission Reduction, EEDI, EEXI & CII -
4 Annex 6 special area
Answer
Annex VI special areas are emission-control zones: Baltic and North Sea with the Channel for SOx, wider seas adding NOx and particulates.
- Baltic and North Sea including the Channel control sulphur with tighter fuel limits.
- US Caribbean controls sulphur, nitrogen oxides and particulates together.
- North American waters out 200 miles control all three from the same date cycle.
- Inside these zones burn compliant fuel or run approved equivalents — the delivery note proves it.
Surveyor follow-up: stem high-sulphur with a working scrubber inside an ECA — compliant or not, and what proves it?
Full theory: MARPOL Annex VI — Emission Reduction, EEDI, EEXI & CII -
5 Garbage management plan - 2 new classes
Answer
The garbage plan names two newer streams beside the classics: cooking oil and fishing-gear plastics with e-waste discipline.
- Classic classes run plastics, food, domestic, cooking oil, incinerator ash, operational waste and fishing gear.
- New attention falls on used cooking oil and derelict fishing gear with e-waste landing rules tightening.
- Discharges follow the 2013 tables by grinding, distance and special areas with the record book proving each.
- Placards, bins and crew training carry the plan — the surveyor reads bins before books.
Surveyor follow-up: cooking oil in the food-waste bin with the plan silent — compliant or not, and what fixes it?
Full theory: MARPOL Annex V — Prevention of Pollution by Garbage from Ships -
6 Importance of nox technical file and what all entered in nox technical file
Answer
The NOx file is the engine’s emission passport: every NOx-touching part and setting recorded for survey by parameter check.
- Records liner, head, piston, rod, pump and valves with settings that shape combustion and emissions.
- High heat past 1000 degrees with heavy load, bad mixture and hot scavenge air makes the NOx the file guards.
- Survey verifies parts and settings against the file — non-identical spares outside limits kill compliance.
- Paired with the EIAPP certificate per engine; changes re-approved and re-recorded before sailing.
Surveyor follow-up: fuel pump renewed non-identical with the file untouched — compliant or not?
Full theory: MARPOL Annex VI — Air Pollution: SOx, NOx & Exhaust Gas Cleaning -
7 of sox and nox?
Answer
SOx comes from fuel sulphur, NOx from hot air: scrub or burn clean for sulphur, cool and time for nitrogen.
- Low-sulphur bunkers cost most and comply simplest inside emission areas.
- Scrubbers wash SOx past 95% with caustic-blended water over exhaust gas.
- NOx falls with cooler scavenge, correct timing and part-load tuning against the technical file.
- Prove by delivery notes, file parameters and CII trends — the surveyor adds the columns.
Surveyor follow-up: high-sulphur stem with a working scrubber inside an ECA — compliant or not, and what proves it?
Full theory: MARPOL Annex VI — Air Pollution: SOx, NOx & Exhaust Gas Cleaning -
8 Nox technical file ? Name the pollutants (all of them) ?
Answer
Annex VI polices the stack: NOx by technical file and EIAPP, SOx by fuel sulphur, plus particulates, VOCs and ozone-depleting gases.
- NOx limited by engine speed curves in Regulation 13 with every setting recorded in the technical file.
- SOx capped by fuel sulphur content and emission-area rules with delivery notes proving compliance.
- Particulates, volatile organics and shipboard incineration fall under the same annex with operating limits.
- Ozone-depleting substances and refrigerants carry their own record books — name the annex, regulation and book together.
Surveyor follow-up: technical file perfect with the EIAPP missing and the delivery notes short — compliant air ship or not?
Full theory: MARPOL Annex VI — Air Pollution: SOx, NOx & Exhaust Gas Cleaning -
9 Dicharge criteria in special areas & orb1 entries. Bunkering fuel in which entry
Answer
Two answers: the special-area oil limits, and bunkering is recorded in the Oil Record Book under its own heading.
- Outside a special area, machinery bilge goes overboard at 15 ppm or less, en route, and not from cargo pump-room bilges.
- Inside a special area that allowance is withdrawn — the effluent is retained, and on ships over 10 000 gross tons the stop device enforces it.
- Bunkering is recorded under the Oil Record Book heading for bunkering of fuel or bulk lubricating oil.
- That entry carries the place and time of bunkering, the type and quantity of fuel and the tank identity, with quantity added and total content.
Surveyor follow-up: bunkering logged with quantity added but not the total content — which column of that entry is missing?
Full theory: MARPOL Annex I — Prevention of Pollution by Oil -
10 Difference bet special area and outside special area pumping bilges
Answer
Outside special areas you may discharge 15-ppm bilges en route; inside them the 15-ppm allowance is withdrawn and most bilge discharge stops.
- Outside special areas, processed bilge from machinery spaces may go overboard if the oil content without dilution is 15 ppm or less.
- The bilge must not come from cargo pump-room bilges, must not be mixed with oil residues, and the ship must be en route.
- Inside special areas that 15-ppm allowance does not apply — the equipment runs and the discharge is stopped, or retained.
- Ships over 10 000 gross tons have the alarm and automatic stopping device, which is what enforces the rule in practice.
Surveyor follow-up: 14 ppm bilge logged inside a special area on a ship over 10 000 GT — compliant, or a special-area breach?
Full theory: MARPOL Annex I — Prevention of Pollution by Oil -
11 Discharge condition in special area
Answer
In a special area the oil content limit still applies but the discharge ban bites: nothing goes overboard except at the stated conditions.
- Oily water from machinery spaces may only be discharged outside special areas, en route, at 15 ppm or less.
- Inside a special area the discharge is prohibited and the effluent is retained, with the alarm and stop device fitted.
- Outside special areas the discharge is permitted en route with the oil filtering equipment in operation and the 15 ppm limit met.
- Discharge through the emergency or overboard inlet without the oil content meter reading is a discharge regardless of intent.
Surveyor follow-up: 12 ppm at the meter inside a special area — does the number save the discharge?
Full theory: MARPOL Annex I — Prevention of Pollution by Oil -
12 Garbage management plan and new amendments?
Answer
The garbage plan exists because Annex V tightened: a ship of 12 m and over needs a plan, placards, and a record of every discharge.
- Every ship of 12 m or more in length overall must display placards notifying the crew of the discharge requirements.
- Placards are written in the working language of the crew, and in English, French or Spanish for ships going to party or offshore terminals.
- Ships of 100 gross tons and above, and those certified to carry hazardous waste, keep the fuller record and the management plan.
- The amendments brought in food waste and the separate e-waste and used oil streams, which is why the category list grew.
Surveyor follow-up: placards in the crew’s language only with no plan on board — is that a record defect or a safety one?
Full theory: MARPOL Annex V — Prevention of Pollution by Garbage from Ships -
13 Guidelines for oil spill
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14 How nox. Calculated
Answer
NOx is nitrogen and oxygen combined by heat: at over 1000°C in the cylinder, atmospheric nitrogen reacts and forms the oxides.
- Nitrogen from the charge air reacts at high temperature — over about 1000°C — and forms nitrogen oxides.
- Heavy load, a poor air-fuel mixture, scavenge air or jacket temperature too high, and a hot liner all raise NOx.
- The technical file records every parameter and component that can influence emissions — liner, head, fuel settings.
- Each engine carries an EIAPP certificate with the tested NOx curve, and survey verifies the engine against that file.
Surveyor follow-up: NOx file complete with one liner replaced outside limits — is the file, the part or the certificate?
Full theory: MARPOL Annex VI — Air Pollution: SOx, NOx & Exhaust Gas Cleaning -
15 How to make sure u r nox compliant?
Answer
NOx compliance is proved on paper and on the fuel: EIAPP certificate, the technical file, and a bunker note below the cap.
- Each engine holds an EIAPP certificate proving its tested NOx curve against the Regulation 13 limits.
- The technical file records every part and setting that can change emissions — liner, head, fuel and injection parameters.
- Fuel sulphur is proved by the bunker delivery note and the retained sample, inside or outside an emission control area.
- So compliance is the certificate plus the file plus the note — and a surveyor checks all three, not the last one.
Surveyor follow-up: EIAPP and file correct with a bunker note over the sulphur cap — which of the three fails?
Full theory: MARPOL Annex VI — Air Pollution: SOx, NOx & Exhaust Gas Cleaning -
16 Methods to compliance with nox tire 3 standards
Answer
Three routes: keep the engine on its certified curve, add in-engine control, or treat the gas after it leaves the cylinder.
- In-engine, cooled external exhaust gas recirculation is the most effective measure, slowing the reaction and lowering peak temperature.
- EGR trades against soot, so it needs higher injection pressure or post-injection to restore the particulate performance.
- Secondary reduction treats the exhaust after the engine, with selective catalytic reduction on NOx and a particulate filter for soot.
- Which tier applies depends on the ship’s date and area, so the answer is the ship’s own standard plus the method she actually fitted.
Surveyor follow-up: new-build tanker with EGR and no SCR after a conversion — which standard was she built to, and which fitted?
Full theory: MARPOL Annex VI — Air Pollution: SOx, NOx & Exhaust Gas Cleaning -
17 Ows reg in special areas
Answer
Inside a special area the oily water separator is still fitted and run, but the 15-ppm overboard allowance goes: discharge is stopped.
- Oil filtering equipment of an approved design must be in operation, and the effluent without dilution must not exceed 15 ppm.
- In a special area the bilge discharge itself is restricted, so the oil is retained in the sludge or bilge tank instead.
- Ships over 10 000 gross tons require the alarm and the automatic stopping device to enforce it.
- A machine that is fitted but not in operation is a breach — the regulation is about operation, not presence.
Surveyor follow-up: separator running and oil level rising in a special area — is the retention the right answer, and who empties the tank?
Full theory: The Bilge System the Separator Serves -
18 Special area regulation for bilge
Answer
In a special area the 15-ppm bilge allowance is withdrawn: the equipment runs, the discharge stops, and the oil is retained.
- Special areas are named: the Mediterranean, Baltic, Red Sea, Black Sea, North Sea, the Gulf of Aden area and the Antarctic.
- The oil filtering equipment must be in operation, but the 15-ppm overboard allowance does not apply there.
- So the effluent goes to the bilge or sludge tank, and the ship retains it until reception facilities are available.
- On ships over 10 000 gross tons the alarm and automatic stopping device are what make that rule enforceable.
Surveyor follow-up: bilge discharge inside a special area with the monitor proved — is the equipment the rule, or the area?
Full theory: MARPOL Annex I — Prevention of Pollution by Oil
Source: 123 written papers and surveyor oral banks, 24,613 entries, merged into 17,210 topics. Ticks are stored on this device only.