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OCTCO/OCTF exit exam questions and answers

All 252 questions from the Oil and Chemical Tanker Cargo Operations (OCTCO/OCTF) exit exam bank, with the correct option marked and a one-line explanation for every one. Read it end to end, jump to a single set, or search it — then sit the same bank as a timed paper. The real DG Shipping exit exam is 30 marks with 15 to pass.

These are the bank's original groupings. Practising deals the whole bank out again every time you reshuffle, so a practice “Set 3” is a different 30 questions each time — the set numbers below are the source file's, and are only used here so the key stays navigable. Options are listed in their original order with fixed letters; when you practise, those move too.

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Set 1 — 30 OCTCO/OCTF exit exam questions with answers

1. What MARPOL Annex regulates prevention of oil pollution from tankers?

  • A. MARPOL Annex I
  • B. MARPOL Annex II
  • C. MARPOL Annex V
  • D. MARPOL Annex III
Answer: A — MARPOL Annex I
MARPOL Annex I contains regulations for preventing oil pollution.

2. What is the maximum oxygen content allowed in inert gas supplied to cargo tanks?

  • A. 21%
  • B. 5% by volume (max 8% inside tanks)
  • C. 0%
  • D. 15%
Answer: B — 5% by volume (max 8% inside tanks)
Inert Gas Systems supply IG with O2 < 5%; tank atmosphere must be < 8% O2.

3. What operation uses crude oil jets to clean sludges from tank walls during discharge?

  • A. Crude Oil Washing (COW)
  • B. Water flushing
  • C. Steam cleaning
  • D. Solvent soaking
Answer: A — Crude Oil Washing (COW)
COW uses crude oil jets to dissolve waxy sludges during discharge.

4. What condition is mandatory before starting Crude Oil Washing (COW)?

  • A. Boiler off
  • B. Tank open to air
  • C. Dry dock
  • D. Cargo tank must be inerted with O2 < 8%
Answer: D — Cargo tank must be inerted with O2 < 8%
COW generates static charges; tank O2 must be below 8% to prevent explosion.

5. What system monitors and controls oily water discharge overboard from slop tanks?

  • A. Salinometer
  • B. OWS 15 ppm alarm
  • C. Echo sounder
  • D. Oil Discharge Monitoring and Control System (ODMCS)
Answer: D — Oil Discharge Monitoring and Control System (ODMCS)
ODMCS logs oil content, discharge rate (L/nm), and total oil discharged.

6. What is the maximum instantaneous rate of oil discharge allowed outside Special Areas under MARPOL Annex I?

  • A. 100 L/nm
  • B. Zero
  • C. 30 liters per nautical mile
  • D. 15 ppm
Answer: C — 30 liters per nautical mile
MARPOL Annex I limits en-route oil discharge to 30 L/nm.

7. What device stops hydrocarbon gas backflowing from cargo tanks into the machinery space?

  • A. Butterfly valve
  • B. Deck Water Seal and Non-Return Valve
  • C. Fan
  • D. Flame screen
Answer: B — Deck Water Seal and Non-Return Valve
The deck water seal provides a water barrier stopping gas backflow to engine room.

8. What instrument measures flammable vapor concentration as a percentage of LEL?

  • A. Explosimeter (Combustible Gas Indicator)
  • B. Dip tube
  • C. Oxygen Analyzer
  • D. Refractometer
Answer: A — Explosimeter (Combustible Gas Indicator)
Explosimeters measure flammable gas concentration up to 100% LEL.

9. What is Reid Vapor Pressure (RVP)?

  • A. Standard measure of crude oil vapor pressure at 100°F (37.8°C)
  • B. Air pressure
  • C. Hydraulic pressure
  • D. Steam pressure
Answer: A — Standard measure of crude oil vapor pressure at 100°F (37.8°C)
RVP indicates oil volatility and vapor evolution tendency.

10. What device protects oil cargo tanks against overpressure or vacuum structural damage?

  • A. High-velocity Pressure/Vacuum (P/V) valve
  • B. Gate valve
  • C. Quick closing valve
  • D. Storm valve
Answer: A — High-velocity Pressure/Vacuum (P/V) valve
P/V valves automatically relieve overpressure or vacuum inside tanks.

11. Under STCW Code Table A-V/1-1-1, what is the mandatory requirement regarding regulatory compliance and STCW code requirements during Basic Oil & Chemical Tanker operations?

  • A. Strict compliance with approved safety procedures and flag state regulations
  • B. Optional adherence based on vessel size
  • C. Applicable only during drydock operations
  • D. Verbal recommendation without documentation
Answer: A — Strict compliance with approved safety procedures and flag state regulations
STCW Code Table A-V/1-1-1 mandates strict compliance with approved safety protocols for Basic Oil & Chemical Tanker.

12. What specific safety precaution must be observed when managing regulatory compliance and STCW code requirements for Basic Oil & Chemical Tanker on board?

  • A. Proceeding without informing the officer on watch
  • B. Conducting a thorough risk assessment and briefing all involved personnel prior to starting work
  • C. Disabling automated safety alarms to save time
  • D. Delegating tasks exclusively to untrained crew members
Answer: B — Conducting a thorough risk assessment and briefing all involved personnel prior to starting work
Risk assessments and pre-job briefings ensure all team members understand hazards during Basic Oil & Chemical Tanker operations.

13. What does ISGOTT stand for?

  • A. International Safety Guide for Oil Tankers and Terminals
  • B. Integrated Offshore Safety
  • C. Indian Safety Group
  • D. System for Gas Safety
Answer: A — International Safety Guide for Oil Tankers and Terminals
ISGOTT is the industry standard safety guide published by ICS, OCIMF, and IAPH.

14. What is the function of an Inert Gas Scrubber tower?

  • A. Cool flue gas and remove soot and SO2 particles
  • B. Generate oxygen
  • C. Separate oil and water
  • D. Heat oil
Answer: A — Cool flue gas and remove soot and SO2 particles
Scrubber towers spray seawater to cool flue gas and remove corrosive SO2 and soot.

15. What is Load on Top (LOT) procedure?

  • A. Pumping without sounding
  • B. Overfilling tanks
  • C. Heavy cargo over light cargo
  • D. Decanting clean water under settled slops and loading fresh crude directly on top
Answer: D — Decanting clean water under settled slops and loading fresh crude directly on top
LOT decants separated water via ODMCS, retaining oil slops to merge with new cargo.

16. What risk occurs if static electricity accumulates during initial filling of an un-inerted tank?

  • A. Corrosion
  • B. Electrostatic spark ignition causing tank explosion
  • C. Freezing
  • D. Cavitation
Answer: B — Electrostatic spark ignition causing tank explosion
Static sparks igniting volatile vapors cause catastrophic tank explosions.

17. What is the max initial loading rate velocity for static accumulator oils before inlet pipe is submerged?

  • A. No limit
  • B. 1 meter per second
  • C. 10 m/s
  • D. 50 m/s
Answer: B — 1 meter per second
Linear velocity is restricted to max 1 m/s initially to prevent static charge generation.

18. What safety system automatically shuts down cargo pumps and closes valves in emergencies?

  • A. Emergency Shutdown System (ESD)
  • B. Windlass brake
  • C. Boiler valve
  • D. Bilge valve
Answer: A — Emergency Shutdown System (ESD)
ESD isolates ship and shore cargo lines instantly in emergency conditions.

19. What equipment measures hydrocarbon vapor concentration in zero-oxygen inert atmospheres?

  • A. Catalytic explosimeter
  • B. Hydrometer
  • C. Litmus paper
  • D. Tankscope / Infrared Gas Analyzer
Answer: D — Tankscope / Infrared Gas Analyzer
Tankscopes measure gas concentrations in inert atmospheres where oxygen is zero.

20. What is total oil discharge limit for existing tankers during ballast voyage under MARPOL Annex I?

  • A. 1/1,000
  • B. 100 m3
  • C. Zero everywhere
  • D. Max 1/30,000 of total cargo carried on previous voyage
Answer: D — Max 1/30,000 of total cargo carried on previous voyage
MARPOL caps total ballast discharge oil volume to 1/30,000 of previous cargo.

21. What is the function of stripping pumps during cargo discharge?

  • A. Drain remaining oil liquid from tank bottoms and suction lines
  • B. Cool main deck
  • C. Generate steam
  • D. Pump ballast into fuel tanks
Answer: A — Drain remaining oil liquid from tank bottoms and suction lines
Stripping pumps remove liquid residues when main centrifugal pumps lose suction.

22. What safety document is signed by ship officer and shore representative prior to cargo transfer?

  • A. Waybill
  • B. Crew Agreement
  • C. Custom Clearance
  • D. Ship / Shore Safety Checklist (SSSCL)
Answer: D — Ship / Shore Safety Checklist (SSSCL)
The SSSCL confirms safety precautions, communications, ESD links, and manifold checks.

23. Which international regulation specifies the minimum standard for regulatory compliance and STCW code requirements concerning Basic Oil & Chemical Tanker?

  • A. Port State Control advisory note only
  • B. International Load Line Certificate Annex 3
  • C. STCW Code Section A-V/1-1-1 and relevant SOLAS/MARPOL conventions
  • D. Tonnage Measurement Convention 1969
Answer: C — STCW Code Section A-V/1-1-1 and relevant SOLAS/MARPOL conventions
STCW Code Section A-V/1-1-1 sets international standards for training and operational competency in Basic Oil & Chemical Tanker.

24. In the event of an emergency involving regulatory compliance and STCW code requirements during Basic Oil & Chemical Tanker tasks, what immediate action is required?

  • A. Wait until the end of the watch to log the issue
  • B. Evacuate the vessel immediately without informing the bridge
  • C. Attempt to resolve the incident silently without raising the alarm
  • D. Raise the alarm, notify the Officer of the Watch, and execute assigned muster list duties
Answer: D — Raise the alarm, notify the Officer of the Watch, and execute assigned muster list duties
Prompt alarm activation ensures emergency response teams can mobilize immediately.

25. What gas present in crude oil vapor is highly toxic with rotten egg smell at low levels?

  • A. Methane
  • B. Nitrogen
  • C. Hydrogen Sulfide (H2S)
  • D. Carbon Dioxide
Answer: C — Hydrogen Sulfide (H2S)
H2S is highly toxic, deadens smell rapidly, and is fatal at high concentrations.

26. What is modern TLV-TWA exposure limit for Hydrogen Sulfide (H2S)?

  • A. 1 ppm to 5 ppm
  • B. 1000 ppm
  • C. 5000 ppm
  • D. 100 ppm
Answer: A — 1 ppm to 5 ppm
Modern ACGIH guidelines specify H2S TLV-TWA of 1 ppm due to high toxicity.

27. What device isolates cargo tank vapor space while maintaining pressure control?

  • A. Sounding cap
  • B. Open stack
  • C. Pressure/Vacuum (P/V) breaker or P/V valves
  • D. Scupper plug
Answer: C — Pressure/Vacuum (P/V) breaker or P/V valves
P/V breakers protect inert gas main lines and tanks from pressure spikes or vacuum.

28. What requirement applies to double hull tankers under MARPOL Annex I?

  • A. Wood lined hold
  • B. Single skin side
  • C. Open bilge
  • D. Double bottom and wing ballast tanks separating cargo tanks from outer hull
Answer: D — Double bottom and wing ballast tanks separating cargo tanks from outer hull
Double hulls protect cargo tanks from rupture during grounding or collision.

29. What action is taken if inert gas oxygen content exceeds 8% during cargo discharge?

  • A. Open tank lids
  • B. Stop cargo discharge immediately and rectify IG plant fault
  • C. Drain scrubber
  • D. Double discharge speed
Answer: B — Stop cargo discharge immediately and rectify IG plant fault
If O2 exceeds 8%, cargo operations must cease until safe inert atmosphere is restored.

30. What is purging on an oil tanker?

  • A. Pumping oil to shore
  • B. Ballasting
  • C. Introducing inert gas into an inerted tank to reduce hydrocarbon concentration before gas freeing
  • D. Washing with seawater
Answer: C — Introducing inert gas into an inerted tank to reduce hydrocarbon concentration before gas freeing
Purging drops hydrocarbon vapor levels low enough that air introduction won't create flammability.

Set 2 — 30 OCTCO/OCTF exit exam questions with answers

1. What is the function of Oil Record Book (Part II) on oil tankers?

  • A. Mandatory log of cargo operations, ballasting, COW, slop discharges, and ODMCS
  • B. Food inventory
  • C. Overtime record
  • D. Engine oil log
Answer: A — Mandatory log of cargo operations, ballasting, COW, slop discharges, and ODMCS
Oil Record Book Part II logs all cargo/ballast operations on tankers under MARPOL.

2. What type of pump is most commonly used as main cargo pump on crude oil tankers?

  • A. High-capacity steam turbine or motor driven centrifugal pump
  • B. Gear pump
  • C. Hand piston pump
  • D. Diaphragm pump
Answer: A — High-capacity steam turbine or motor driven centrifugal pump
Centrifugal cargo pumps provide high volume transfer rates (1500 to 5000 m3/h).

3. What safety feature is mandatory on cargo pump room ventilation systems?

  • A. Air recirculation
  • B. Continuous extraction ventilation (at least 20 air changes per hour) under negative pressure
  • C. Small fan
  • D. No ventilation
Answer: B — Continuous extraction ventilation (at least 20 air changes per hour) under negative pressure
Extraction fans draw heavy petroleum vapors from floor level, keeping pump room safe.

4. What is auto-ignition temperature of a flammable liquid?

  • A. Vacuum boiling point
  • B. Sea temp
  • C. Lowest temperature at which vapor ignites spontaneously without external spark
  • D. Freezing point
Answer: C — Lowest temperature at which vapor ignites spontaneously without external spark
Hot engine exhaust pipes above auto-ignition temp can ignite cargo leaks without a spark.

5. How frequently must operational drills and practical checks for regulatory compliance and STCW code requirements be conducted for Basic Oil & Chemical Tanker?

  • A. At least monthly or as mandated by SOLAS and shipboard safety management system (SMS)
  • B. Once every 5 years during special survey
  • C. Only when requested by port State control inspectors
  • D. Annually prior to vessel drydocking
Answer: A — At least monthly or as mandated by SOLAS and shipboard safety management system (SMS)
Regular drills maintain crew emergency readiness and satisfy SOLAS requirements.

6. What documented record must be maintained on board following completion of tasks related to regulatory compliance and STCW code requirements in Basic Oil & Chemical Tanker?

  • A. No written record is required
  • B. Entry in the official Deck or Engine Logbook recording date, time, and operational parameters
  • C. Verbal update to port agent without logging
  • D. Unsigned note on the shipboard notice board
Answer: B — Entry in the official Deck or Engine Logbook recording date, time, and operational parameters
Official logbook entries provide mandatory legal documentation of shipboard safety tasks.

7. What is the purpose of flame screens fitted on tank vent outlets?

  • A. Keep birds out
  • B. Prevent passage of external sparks/flames into cargo tank vapor space
  • C. Stop liquid splash
  • D. Filter dust
Answer: B — Prevent passage of external sparks/flames into cargo tank vapor space
Fine wire gauze dissipates flame heat below ignition temperature, stopping flame entry.

8. What does SOPEP stand for?

  • A. Standard Operational Protocol
  • B. Shipboard Oil Pollution Emergency Plan
  • C. System for Oil Prevention
  • D. Safety Officer Program
Answer: B — Shipboard Oil Pollution Emergency Plan
SOPEP is a mandatory onboard plan detailing emergency responses to oil spills.

9. What is ullage in a cargo tank?

  • A. Distance from liquid surface up to reference point at top of sounding pipe
  • B. Engine room air volume
  • C. Total cargo weight
  • D. Depth of liquid
Answer: A — Distance from liquid surface up to reference point at top of sounding pipe
Ullage measures empty height above liquid level; Sounding measures liquid height from bottom.

10. Why must cargo manifolds be fitted with blank flanges bolted with full set of bolts when not in use?

  • A. Provide positive secondary liquid/vapor containment against valve leakage
  • B. Keep manifold painted
  • C. Weight balance
  • D. Improve appearance
Answer: A — Provide positive secondary liquid/vapor containment against valve leakage
Blank flanges with complete bolting prevent accidental oil spills if valves seep.

11. What is the primary cause of sloshing damage in partially filled cargo tanks?

  • A. Pump suction
  • B. Inert gas fan vibration
  • C. High cargo temp
  • D. Violent movement of liquid cargo creating severe dynamic impact pressures against bulkheads
Answer: D — Violent movement of liquid cargo creating severe dynamic impact pressures against bulkheads
Sloshing forces in partially filled slack tanks can damage internal bulkheads and heating coils.

12. What equipment measures oil content in water discharging from bilges or slop tanks?

  • A. Thermometer
  • B. Flow meter
  • C. Tachometer
  • D. Oil Content Meter (OCM) / 15 ppm alarm
Answer: D — Oil Content Meter (OCM) / 15 ppm alarm
OCMs monitor oil concentration in discharge water under MARPOL limits.

13. What precaution must be observed when taking manual oil soundings on an inerted tanker?

  • A. Use nylon rope
  • B. Use vapor-lock valves and metallic sounding tapes properly grounded/bonded to ship structure
  • C. Open main hatch wide
  • D. Stand barefoot
Answer: B — Use vapor-lock valves and metallic sounding tapes properly grounded/bonded to ship structure
Grounding sounding tapes prevents static sparks inside cargo vapor spaces during dips.

14. What is the function of cargo tank heating coils on oil tankers?

  • A. Wash tank walls
  • B. Boil cargo into gas
  • C. Cool down cargo
  • D. Maintain cargo temperature to reduce viscosity for efficient pumping
Answer: D — Maintain cargo temperature to reduce viscosity for efficient pumping
Steam/thermal heating coils keep heavy oils liquid above their pour point for easy pumping.

15. What is a Segregated Ballast Tank (SBT)?

  • A. Engine sump
  • B. Drinking water tank
  • C. Slop tank
  • D. Ballast tank completely separate from cargo oil system, filled only with clean sea water
Answer: D — Ballast tank completely separate from cargo oil system, filled only with clean sea water
SBT systems prevent seawater contamination by keeping ballast completely isolated from cargo.

16. What condition requires immediate stopping of oil cargo transfer?

  • A. Sunset
  • B. Cargo spill on deck, manifold valve leakage, sudden pressure drop, or lightning storm
  • C. Radio broadcast start
  • D. Change of steering helm
Answer: B — Cargo spill on deck, manifold valve leakage, sudden pressure drop, or lightning storm
Any containment failure or atmospheric hazard requires immediate operational shutdown.

17. What type of personal protective equipment (PPE) is essential when handling regulatory compliance and STCW code requirements under Basic Oil & Chemical Tanker guidelines?

  • A. Standard street clothing with rubber gloves
  • B. Basic cotton coveralls without eye or foot protection
  • C. High-visibility vest only
  • D. Certified task-specific PPE meeting SOLAS/IMO performance standards
Answer: D — Certified task-specific PPE meeting SOLAS/IMO performance standards
Approved PPE protects personnel against specific physical and chemical hazards.

18. What parameter must be verified prior to authorizing enclosed space entry for regulatory compliance and STCW code requirements related to Basic Oil & Chemical Tanker?

  • A. Oxygen level at 15% with ventilation turned off
  • B. Atmospheric oxygen level at 20.9% and zero toxic/flammable gas concentration
  • C. Temperature check only
  • D. Visual inspection through access hatch without gas testing
Answer: B — Atmospheric oxygen level at 20.9% and zero toxic/flammable gas concentration
Enclosed space safety requires verified atmospheric gas testing prior to entry.

19. What is the Lower Explosive Limit (LEL) of typical crude oil hydrocarbon vapors in air?

  • A. 20%
  • B. 50%
  • C. Approximately 1% by volume
  • D. 0.01%
Answer: C — Approximately 1% by volume
Crude oil vapors become flammable at ~1% LEL and reach Upper Explosive Limit at ~10%.

20. What is the role of an Oil Spill Removal Organization (OSRO)?

  • A. Provide containment booms, skimmers, and professional cleanup assistance
  • B. Inspect engine certificates
  • C. Operate cargo pumps
  • D. Issue bill of lading
Answer: A — Provide containment booms, skimmers, and professional cleanup assistance
OSRO contractors provide specialized spill response hardware and cleanup operations.

21. Why is water prohibited as an extinguishing agent directly on liquid oil pool fires?

  • A. Water turns oil to gas
  • B. Water is heavier than oil; oil floats on top and spreads burning liquid over wider area
  • C. Water freezes oil
  • D. Water generates oxygen
Answer: B — Water is heavier than oil; oil floats on top and spreads burning liquid over wider area
Water streams sink below burning oil, causing violent boiling and fire spread. Foam is used.

22. What fire extinguishing system is standard protection for oil tanker cargo deck areas?

  • A. CO2 gas flooding open deck
  • B. Sprinkler fresh water
  • C. Fixed Deck Foam System (Low expansion foam)
  • D. Halon gas
Answer: C — Fixed Deck Foam System (Low expansion foam)
Deck foam monitors smother liquid fuel surface fires by sealing off flammable vapors from air.

23. What is the purpose of ballast water exchange (BWE) under BWM Convention?

  • A. Cool deck
  • B. Replace coastal ballast water with open-ocean deep sea water to prevent invasive species transfer
  • C. Clean fuel tanks
  • D. Wash cargo lines
Answer: B — Replace coastal ballast water with open-ocean deep sea water to prevent invasive species transfer
Ballast exchange in deep sea (>200 nm, 200m depth) eliminates coastal invasive marine pests.

24. What device measures ullage, oil/water interface level, and temperature with a single portable probe?

  • A. MMC / UTI (Ullage-Temperature-Interface) portable tape
  • B. Wooden dipstick
  • C. Glass thermometer
  • D. Hydrometer
Answer: A — MMC / UTI (Ullage-Temperature-Interface) portable tape
UTI tapes attach to vapor locks, sounding liquid surface, oil-water interface, and temperature.

25. What is gas freeing on an oil tanker?

  • A. Heating cargo
  • B. Closing all vents
  • C. Filling tank with crude
  • D. Replacing hydrocarbon or inert gas in cargo tanks with fresh breathable air
Answer: D — Replacing hydrocarbon or inert gas in cargo tanks with fresh breathable air
Gas-freeing uses high-capacity blowers to introduce fresh air after purging hydrocarbons with inert gas.

26. What risk occurs if a cargo pump is run dry without liquid flow?

  • A. Paint peeling
  • B. Deck freezing
  • C. Electrical short circuit
  • D. Overheating of mechanical seals and bearings, causing fire hazard or pump seizure
Answer: D — Overheating of mechanical seals and bearings, causing fire hazard or pump seizure
Cargo pumps rely on liquid flow for cooling; dry running causes rapid frictional heating.

27. What publication specifies standard communication signals between ship and tugs during berthing?

  • A. Medical Guide
  • B. Standard Marine Communication Phrases (SMCP) / Port Berthing Plan
  • C. Cookery Guide
  • D. Engine Telegraph Manual
Answer: B — Standard Marine Communication Phrases (SMCP) / Port Berthing Plan
SMCP ensures standardized clear VHF communication between pilot, master, tugs, and mooring crew.

28. Who has ultimate responsibility for the safety of cargo operations and environmental compliance on an oil tanker?

  • A. Shore pump operator
  • B. Customs inspector
  • C. The Ship's Master
  • D. Port Agent
Answer: C — The Ship's Master
The Master retains overarching responsibility for overall safety, vessel seaworthiness, and MARPOL compliance.

29. What key responsibility belongs to seafarers performing watchkeeping duties for regulatory compliance and STCW code requirements under Basic Oil & Chemical Tanker?

  • A. Leaving watchkeeping station unattended
  • B. Operating equipment beyond design pressure limits
  • C. Bypassing safety trips during routine operations
  • D. Continuous monitoring of operational parameters and immediate reporting of anomalies
Answer: D — Continuous monitoring of operational parameters and immediate reporting of anomalies
Continuous vigilance and prompt communication are core watchkeeping duties under STCW.

30. Which document contains detailed hazard data and emergency handling instructions for substances involved in regulatory compliance and STCW code requirements during Basic Oil & Chemical Tanker?

  • A. Ship's Cargo Manifest summary page
  • B. Bill of Lading description
  • C. Safety Data Sheet (SDS) / Material Safety Data Sheet (MSDS)
  • D. Crew List document
Answer: C — Safety Data Sheet (SDS) / Material Safety Data Sheet (MSDS)
Safety Data Sheets provide critical hazard identification, PPE requirements, and first aid response steps.

Set 3 — 30 OCTCO/OCTF exit exam questions with answers

1. What is the alternative means of supply of sea water to the deck seal unit in case of maintenance or failure of designated deck seal Pump?

  • A. Through the deck fire line
  • B. Through the main sea water pump or the cargo condenser pump
  • C. Through the deck seal pump fitted in the engine room
  • D. Through a sea water aggregate pump fixed on the cargo deck
Answer: B — Through the main sea water pump or the cargo condenser pump
If the designated deck seal pump fails or is undergoing maintenance, sea water supply to the inert gas deck seal can be alternatively lined up from the main sea water service line or cargo condenser cooling pump.

2. Expand the abbreviation 'ESD' system?

  • A. Emergency stop and disconnect system
  • B. Emergency shut down system
  • C. Emergency shore disconnection system
  • D. Emergency shutting and disconnecting system
Answer: B — Emergency shut down system
ESD stands for Emergency Shut Down system, which is designed to safely stop cargo transfer operations in the event of an emergency.

3. Chapter 4 MARPOL annex VI was adopted on?

  • A. 17th August 2009
  • B. 1st March 2012
  • C. 1St January 2010
  • D. 15th July 2011
Answer: D — 15th July 2011
Chapter 4 of MARPOL Annex VI (Regulations on energy efficiency for ships, including EEDI and SEEMP) was adopted on 15th July 2011 under Resolution MEPC.203(62).

4. A centrifugal bilge pump requires priming?

  • A. In order to overcome the potential energy of water in the discharge line.
  • B. Primarily to lubricate the shaft.
  • C. Due to the inability of this type of pump to lift water to cover the suction(eye)) of the empeller.
  • D. To initially unload the pump by having its head pressure equal to discharge pressure
Answer: C — Due to the inability of this type of pump to lift water to cover the suction(eye)) of the empeller.
Centrifugal pumps are not self-priming because they cannot create a sufficient vacuum with air/vapour to draw liquid into the impeller eye; hence, priming is required to fill the casing and suction.

5. A scrubber tower which is normally acts as a _____.

  • A. Heater
  • B. Cooler
  • C. Humidifier
  • D. Dehumidifier
Answer: B — Cooler
The scrubber tower cools the hot flue gas from the boiler by direct contact with seawater spray and removes sulphur dioxide (SO2) and soot particles.

6. On many modern VLCC tankers which of the following device is used to top up IG pressure on loaded condition in case of slight reduce in tank temperature.

  • A. Supplement IG by the boiler and standard method.
  • B. Do not fire the main boiler plant due to excess fuel consumption which is more than allowed in the agreement
  • C. A separate IGG plant if installed separately
  • D. Wat till the discharge port, open tank vent to allow a little rise in tank pressure.
Answer: A — Supplement IG by the boiler and standard method.
When tank temperature drops causing tank pressure to decrease during loaded passage, inert gas pressure is maintained by topping up from the boiler flue gas system using standard procedures.

7. What is handy size tanker.

  • A. Tankers of about 12000 to 25000 DWT.
  • B. From 26000 to 16500 tdw
  • C. Under 16,500 DWT
  • D. from 36000 to 26000 tdw
Answer: A — Tankers of about 12000 to 25000 DWT.
Handy size tankers generally refer to smaller product or chemical tankers typically in the range of 12,000 to 25,000 DWT.

8. Before cargo operations begin the responsible person on board and the terminal representative will complete___?

  • A. Meeting agreement
  • B. Ship / shore operation plan
  • C. Ship details plan
  • D. Ship / shore safety check list
Answer: D — Ship / shore safety check list
In accordance with ISGOTT guidelines, the Ship/Shore Safety Checklist (SSSCL) must be jointly verified and signed by the responsible ship officer and terminal representative prior to starting cargo operations.

9. In theory, a cargo pump should be able to draw up a liquid to a height equaling atmospheric pressure. This would be approximately ___?

  • A. 30 meters
  • B. 15 meters
  • C. 5 meters
  • D. 10 meters
Answer: D — 10 meters
Standard atmospheric pressure (101.3 kPa / 1.013 bar) corresponds to a theoretical water column height of approximately 10.33 meters.

10. In flue gas line. It would be advantageous to fit _______door downstream from the flue gas valve?

  • A. Inspection
  • B. Access
  • C. both a and b
  • D. None of the above
Answer: C — both a and b
Fitting inspection and access doors downstream of the flue gas isolating valve allows inspection, cleaning of soot deposits, and maintenance of the line and valve seal.

11. The depth of the space in a tank not occupied by oil. same as ullage. It is measured from the flange of the ullage hole to the surface of the space left in petroleum product container to allow for expansion as a result of temperature chages during shipment and use,?

  • A. Innage
  • B. Outage (Ullage)
  • C. Sounding
  • D. Air volume
Answer: B — Outage (Ullage)
Outage (Ullage) is the distance from the designated reference point (ullage port flange) down to the surface of the liquid in the tank.

12. A cargo educator casing normally made of which of the following material?

  • A. Phosphor bronze cast
  • B. Specially made cast steel
  • C. Cast iron
  • D. Stainless steel
Answer: A — Phosphor bronze cast
Cargo stripping eductor casings are commonly cast from phosphor bronze or gunmetal due to excellent corrosion resistance and non-sparking properties in seawater/hydrocarbon service.

13. Chapter __ of the code contains special requirements which are cargos specific and which must be complied with only if that specification is to be carried.

  • A. 14
  • B. 15
  • C. 16
  • D. 17
Answer: D — 17
Chapter 17 of the IBC Code contains the Summary of Minimum Requirements (cargo-specific operational and design requirements for chemical cargoes).

14. What is the meaning of non-volatile cargo?

  • A. Flash point below 65 c
  • B. Flash point above 60 c
  • C. Flash point above 65 c
  • D. Flash point below 60 c
Answer: B — Flash point above 60 c
According to ISGOTT and tanker safety standards, non-volatile petroleum is defined as petroleum having a closed-cup flashpoint of 60°C (140°F) or above.

15. What is the meaning of volatile cargo?

  • A. Flash point below 65 c
  • B. Flash point above 60 c
  • C. Flash point above 65 c
  • D. Flash point below 60 c
Answer: D — Flash point below 60 c
According to ISGOTT, volatile petroleum is defined as petroleum having a closed-cup flashpoint of below 60°C (140°F).

16. The __ should be fitted with suitable inspection & drainage arrangements?

  • A. Mast riser
  • B. PV valve
  • C. PV breaker
  • D. All the above
Answer: D — All the above
Venting system components including mast risers, P/V valves, and P/V breakers must have inspection and drainage provisions to prevent liquid accumulation and blockage.

17. ____ such as petrol (motor spirit) and diesel oil tend to be liquid under normal atmosphere?

  • A. Intermediate molecule
  • B. Very heavy molecules
  • C. Very light molecules
  • D. None of these
Answer: A — Intermediate molecule
Hydrocarbons with intermediate molecular weights (approx C5 to C20, like gasoline, kerosene, and diesel) exist as liquids at normal atmospheric temperature and pressure.

18. A phrase sometimes used to describe an action or procedure that is not committed to writing. but which has been followed for a long time. and considered standard practice by practitioners in the trade.

  • A. Natural Limitation
  • B. Custom of the Trade
  • C. Both
  • D. none of the above
Answer: B — Custom of the Trade
'Custom of the Trade' refers to traditional, long-established practices accepted as standard operating norms in maritime shipping.

19. What types of ships are commonly known as pre-MARPOL tankers?

  • A. A ship which does not comply with the requirements for protectively located segregated ballast tanks
  • B. A category 2 oil tanker
  • C. A ship which do comply with die requirements for protectively located segregated ballast tank
  • D. A category 3 oil tanker
Answer: A — A ship which does not comply with the requirements for protectively located segregated ballast tanks
Pre-MARPOL tankers are older tankers constructed before the enforcement of MARPOL 73/78 regulations requiring protectively located segregated ballast tanks (PL/SBT) and double hulls.

20. Tankers of similar size to parcel tankers but with fewer cargo tanks, mostly of coated steel rather than stainless, and less sophisticated pump and line arrangements. Such ships carry the less difficult chemicals, and also trade extensively with clean oil products.

  • A. Genral Product tanker
  • B. Utility chemical tanker
  • C. Product / Chemical tanker
  • D. Special Chemical tanker
Answer: C — Product / Chemical tanker
Product/Chemical tankers have coated tanks and can alternate between clean refined petroleum products and less aggressive/easy chemical cargoes.

21. What are easy chemicals____?

  • A. Calcium carbonate
  • B. Hydrogen chloride
  • C. Sodium hydroxide
  • D. All of the above
Answer: D — All of the above
'Easy chemicals' are commodity bulk chemicals that do not require specialized high-grade stainless steel or complex inhibitor management under typical carriage.

22. In a sample of ethyl Ethanoate (CH3 COOC2H5) THE TWO oxygen atoms have the same number of electrons but different numbers of neutrons. Which of the following is the correct reason for it?

  • A. One of the oxygen atoms has gained electrons
  • B. One of the oxygen atoms has gained two neutrons
  • C. The two oxygen atoms are isotopes
  • D. The two oxygen atoms are isobars
Answer: C — The two oxygen atoms are isotopes
Atoms of the same element having the same number of protons and electrons (same atomic number) but different numbers of neutrons (different mass numbers) are called isotopes.

23. PV valve is fitted at?

  • A. Common IG line
  • B. Cargo Pipeline
  • C. Individual cargo tanks
  • D. none of these
Answer: C — Individual cargo tanks
Pressure/Vacuum (P/V) valves are fitted to individual cargo tanks or individual tank vent lines to protect tanks against over-pressurization and vacuum during thermal variations.

24. Typically, up to 40,000 tonnes deadweight with multiple small cargo tanks - up to 54 - each with an individual pump and a dedicated pipeline, to carry small parcels of high grade chemicals. These ships have a significant proportion of the cargo tanks made with stainless steel, allowing maximum flexibility to carry cargoes that need their quality safeguarded.

  • A. Sophisticated parcel chemical tankers:
  • B. Complicated Chemical tanker
  • C. Afra max chemical tanker
  • D. None of these
Answer: A — Sophisticated parcel chemical tankers:
Sophisticated parcel chemical tankers are designed with numerous stainless steel cargo tanks, independent submerged pumps, and dedicated piping to carry high-purity, aggressive, or sensitive chemical parcels simultaneously.

25. During loading. firefighting equipment should be laid out ready for use in the vicinity of the?

  • A. Engine room
  • B. Pump Room
  • C. Stern manifold
  • D. none of these
Answer: D — none of these
During cargo operations, portable dry chemical powder extinguishers and charged fire hoses must be rigged and ready for immediate deployment in the vicinity of the active cargo manifold on deck.

26. Is cubic limitation: - this is usually caused by loading a light crude (crude with high API) or clean products?

  • A. Reaching cargo tank capacity before vessel immerses to its load-line
  • B. Loading in all cargo and slop tanks
  • C. Loading maximum till the maximum load line
  • D. Loading till the orders of the cargo receiver
Answer: A — Reaching cargo tank capacity before vessel immerses to its load-line
Cubic limitation (volumetric capacity limit) occurs when low-density (high API gravity) cargo fills 100% of the available tank volume before the ship reaches its maximum permissible deadweight/draft mark.

27. Which of the following methods applies to how a vacuum is created by a jet pump or an eductor?

  • A. A propeller drawing a fluid through a Venturi nozzle.
  • B. A reciprocating plunger directly applying force to a fluid.
  • C. A rapidly moving stream of fluid passing through a nozzle.
  • D. Centrifugal force converted into potential energy.
Answer: C — A rapidly moving stream of fluid passing through a nozzle.
An eductor operates on the Venturi principle: high-velocity driving fluid pumped through a convergent nozzle creates a low-pressure area (vacuum) that entrains suction liquid.

28. General arrangement plan-A drawing of a ship which lists all necessary statistics and operating information such as?

  • A. LOA, SDWT, cargo, water, fuel capacity etc.
  • B. type of cargo and ships
  • C. water ballast exchange log
  • D. all of the above
Answer: A — LOA, SDWT, cargo, water, fuel capacity etc.
The General Arrangement (GA) plan outlines the overall layout, compartment divisions, principal dimensions (LOA, beam, draft), and tank capacities of the vessel.

29. The Convention that allows States to intervene in a pollution incident at sea is the?

  • A. MARPOL Convention
  • B. SOLAS Convention
  • C. CLC Convention
  • D. Intervention Convention
Answer: D — Intervention Convention
The International Convention Relating to Intervention on the High Seas in Cases of Oil Pollution Casualties (1969) empowers coastal states to take preventive measures beyond territorial waters.

30. When doing an enclosed space rescue, the person in charge must coordinate the rescue:

  • A. From inside the space
  • B. From the Bridge
  • C. From outside the space
  • D. From the Engine Control Room
Answer: C — From outside the space
In an enclosed space rescue, the person in charge must remain outside the space at the entrance to coordinate communications, resources, and emergency services effectively.

Set 4 — 30 OCTCO/OCTF exit exam questions with answers

1. Lung inflammation will cause:

  • A. Breathlessness and drowsiness
  • B. Breathlessness and confusion
  • C. Breathlessness and a dry cough
  • D. Breathlessness and slurred speech
Answer: C — Breathlessness and a dry cough
Lung inflammation, chemical inhalation, or toxic vapour irritation in the respiratory tract typically presents with breathlessness and a dry, persistent cough.

2. The portable air operated salvage pumps used for spillage cleanup operation on tanker shall be deployed at?

  • A. The aft end of each side of poop deck
  • B. The forward end of each side of main deck
  • C. The midship on each side of main deck
  • D. The aft end of each side of main deck
Answer: D — The aft end of each side of main deck
Portable air-operated salvage/wilden pumps used for spillage clean-up on oil tankers are deployed at the aft end of each side of the main deck near the aft saveall/scupper containment area.

3. Aquatic toxicity of chemicals is categorized as?

  • A. D1 and D2
  • B. Cl and C2
  • C. Bl and B2
  • D. Al and A2
Answer: C — Bl and B2
Aquatic toxicity of chemicals under GESAMP/MARPOL categorization is evaluated under columns B1 (acute aquatic toxicity) and B2 (chronic aquatic toxicity).

4. With reference to Marpol Annex I, the southern south African area Is?

  • A. Protected area
  • B. Special control area
  • C. Special area
  • D. Restricted area
Answer: C — Special area
Under MARPOL Annex I, the Southern South African waters area is designated as a Special Area for the prevention of oil pollution.

5. The area where emissions of SOx, Nox and PM from ships are controlled is called as?

  • A. Emission control area (ECA)
  • B. Special area (SA)
  • C. Special emission control area (SECA)
  • D. Pollution control area (PCA)
Answer: A — Emission control area (ECA)
Areas where airborne emissions of SOx, NOx, and Particulate Matter (PM) from ships are strictly limited under MARPOL Annex VI are known as Emission Control Areas (ECAs).

6. Containment and Damage Control: which step Is of highest importance for damage control?

  • A. All personnel entering a contaminated space shall enter with another individual
  • B. For each pair entering a space, a trained person with appropriate equipment will be on standby.
  • C. Actions toward controlling the immediate spread of the spill
  • D. Action steps minimizing the Impact to the ship and crew.
Answer: C — Actions toward controlling the immediate spread of the spill
In emergency spill response and damage control, taking immediate action to stop the leak and control the rapid spread of the spill is of highest operational priority.

7. After use of portable foam extinguisher, the equipment is well flushed with water to keep?

  • A. The system is clean.
  • B. Ready for re use.
  • C. The nozzles clear and prevent clogging.
  • D. None of the above
Answer: C — The nozzles clear and prevent clogging.
After use, portable foam extinguishers and branchpipes must be thoroughly flushed with clean fresh water to remove residual foam compound and prevent nozzle clogging.

8. Water extinguishes a fire by?

  • A. Heat removal or cooling
  • B. Smothering or oxygen exclusion
  • C. Flame inhibition
  • D. Fuel limitation
Answer: A — Heat removal or cooling
Water extinguishes fire primarily by cooling—absorbing vast amounts of heat energy as it converts into steam, bringing the fuel temperature below its ignition point.

9. Which part is included to the Fire Triangle to extend it to the Fire Tetrahedon:

  • A. Heat
  • B. Chain reaction
  • C. Fuel
  • D. Oxygen
Answer: B — Chain reaction
The fire tetrahedron expands the fire triangle by adding the fourth essential element: the uninhibited chemical chain reaction.

10. Foam extinguishes a fire by?

  • A. Heat removal or cooling
  • B. Smothering or oxygen exclusion
  • C. Flame inhibition
  • D. Chain reaction
Answer: B — Smothering or oxygen exclusion
Foam extinguishes flammable liquid fires primarily by blanketing the surface, thereby smothering the fire and excluding oxygen from the fuel vapours.

11. What is very important to be carried out after use of deck foam system?

  • A. Stop all pumps for deck foam system.
  • B. Close all valves in the system.
  • C. Flush the system complete with sea water.
  • D. Clean the foam tank.
Answer: C — Flush the system complete with sea water.
After operating a deck foam firefighting system, the entire piping network must be thoroughly flushed with seawater/freshwater to prevent corrosive foam concentrate from hardening and clogging the pipes and monitors.

12. Fixed dry chemical powder extinguishers are mostly used in:

  • A. Oil tankers.
  • B. Passenger vessels.
  • C. Chemical tankers.
  • D. Bulk carriers.
Answer: C — Chemical tankers.
Fixed dry chemical powder (DCP) extinguishing systems are commonly installed on chemical tankers and gas carriers for rapid flame inhibition and three-dimensional gas/chemical fire knockdown.

13. During transit of a vessel if chemical fire occurs, the vessel should:

  • A. Stop and allow other ships to proceed.
  • B. Reduce vessel speed to minimum possible.
  • C. Steer clear of other vessels.
  • D. Anchor immediately.
Answer: C — Steer clear of other vessels.
If a chemical fire occurs on board a vessel during transit, the vessel should immediately alter heading to keep clear of other ships and position the wind to blow smoke away from the accommodation.

14. The electrostatic field strength which is sufficient to cause breakdown of air or petroleum gases is about?

  • A. 5000 Kilovolts/meter
  • B. 3000 Kilovolts/meter
  • C. 3000 Volts/ meter
  • D. 5000 Volts/meter
Answer: B — 3000 Kilovolts/meter
An electrostatic field strength of approximately 3,000 kilovolts per meter (3 kV/mm) is required to break down the dielectric strength of air or petroleum gas and cause an incendiary spark discharge.

15. A crew member is unconscious and the face is flushed. You should ___?

  • A. Lay the crew member down with the head and shoulders slightly raised
  • B. Administer a liquid stimulant
  • C. Lay the crew member down with the head lower than the feet
  • D. Attempt to stand the crew member upright to restore consciousness
Answer: A — Lay the crew member down with the head and shoulders slightly raised
For an unconscious casualty with a flushed (red) face, position them lying down with the head and shoulders slightly elevated to reduce cranial blood pressure.

16. What is the range of expansion ratio for high expansion foams?

  • A. 1000: 1
  • B. 5: 1 to 15: 1
  • C. 1250 liters/ min
  • D. 1000 liters/ min
Answer: A — 1000: 1
High-expansion foam systems produce foam with an expansion ratio typically up to 1000:1, allowing large enclosed spaces like engine rooms or pump rooms to be flooded quickly.

17. What is the least a person should do before entering machinery spaces?

  • A. Wear appropriate personal protective equipment
  • B. Inform the bridge
  • C. Inform his superiors
  • D. Check oxygen level
Answer: A — Wear appropriate personal protective equipment
Before entering machinery spaces, seafarers must always wear required personal protective equipment (PPE) including safety shoes, boiler suit, helmet, and ear defenders.

18. What is the least you must do before entering a cofferdam in the engine room?

  • A. Open up the manhole and enter the cofferdam
  • B. Complete an enclosed space checklist
  • C. Enter the cofferdam and simultaneously start ventilation
  • D. Check lighting only
Answer: B — Complete an enclosed space checklist
Before entering any cofferdam or enclosed compartment, a full enclosed space entry risk assessment and checklist (including multi-gas atmosphere testing) must be completed and signed by authorized officers.

19. TLV-STEL is the spot exposure of a chemical substance for a duration of:

  • A. S minutes
  • B. 15 minutes
  • C. 30 minutes
  • D. 60 minutes
Answer: B — 15 minutes
TLV-STEL (Threshold Limit Value - Short Term Exposure Limit) is the maximum concentration to which workers can be exposed continuously for a short period of 15 minutes without suffering adverse health effects.

20. What is pour point ?

  • A. The temperature at which oil gets frozen
  • B. The lowest temperature at which petroleum oil will remain fluid
  • C. The temperature at which oil cannot be discharged
  • D. The temperature at which oil needs to be heated
Answer: B — The lowest temperature at which petroleum oil will remain fluid
Pour point is defined as the lowest temperature at which a petroleum oil or liquid remains fluid and will pour or flow under standardized test conditions.

21. What is non-volatile petroleum?

  • A. Petroleum having a flashpoint of 60 Degrees C or above
  • B. Petroleum having a flashpoint of 60 Degrees C or below
  • C. Petroleum having a flashpoint of 100 Degrees C or above
  • D. Petroleum having a flashpoint of 100 Degrees C or below
Answer: A — Petroleum having a flashpoint of 60 Degrees C or above
Non-volatile petroleum is defined in ISGOTT as petroleum having a flashpoint of 60°C (140°F) or above.

22. What is the lower flammable limit?

  • A. The concentration of a hydrocarbon gas in air below which there is insufficient hydrocarbon to support combustion
  • B. The limit where there is insufficient oxygen to support combustion
  • C. The limit where there is too much oxygen to support combustion
  • D. The limit for man entry of personnel into tanks
Answer: A — The concentration of a hydrocarbon gas in air below which there is insufficient hydrocarbon to support combustion
The Lower Flammable Limit (LFL) is the minimum concentration of hydrocarbon gas in air below which there is insufficient fuel to support combustion (the mixture is too lean).

23. What is cold work?

  • A. Carrying out work in a cold atmosphere
  • B. Work that cannot create a source of ignition
  • C. Carrying out work on reefer containers
  • D. Work that can be done only in cold temperatures
Answer: B — Work that cannot create a source of ignition
Cold work refers to maintenance, inspection, or repairs that do not involve heat, flames, or the potential generation of an ignition source or spark.

24. The most common measure taken on tankers to avoid static discharge is:

  • A. Closed ullaging
  • B. Use of only approved PPE on deck
  • C. Bonding and grounding
  • D. Having continuous pipe lengths.
Answer: C — Bonding and grounding
Static electrical accumulation and dangerous potential differences on tankers are avoided by bonding and grounding all pipes, hoses, and metal structures to the ship hull.

25. The permit towork should not last for more than?

  • A. 12 hours
  • B. 24 hours
  • C. 36 hours
  • D. 48 hours
Answer: B — 24 hours
A standard permit to work (PTW) for hot work or enclosed space entry is issued for a specific task and is valid for a maximum duration of 24 hours (or one work shift).

26. What is a hot work permit?

  • A. Document used for carrying out repairs under super vision
  • B. A document issued by the person responsible permitting specific hot work to be done during a particular time interval in a defined space
  • C. Document used for work in a dry-dock
  • D. Document valid for 7 days for carrying out tank cleaning
Answer: B — A document issued by the person responsible permitting specific hot work to be done during a particular time interval in a defined space
A hot work permit is a written safety document issued by an authorized responsible person permitting specific hot work within a designated space and timeframe following rigorous safety checks.

27. H2S gas is:

  • A. Less toxic
  • B. Inflammable
  • C. Toxic, corrosive and flammable
  • D. Non-toxic
Answer: C — Toxic, corrosive and flammable
Hydrogen sulphide (H2S) is a highly toxic, corrosive, and flammable gas with a characteristic rotten-egg odor at low concentrations.

28. Electrons have:

  • A. No charge
  • B. Positive charge
  • C. Negative charge
  • D. Neutral charge
Answer: C — Negative charge
Electrons are subatomic particles carrying a negative electric charge.

29. How to reduce Hydrogen Sulphide Hazard in Residual Fuel Oils?

  • A. Ventilation to lower the concentration of vapor in the ullage space and in specific areas where vapors may accumulate should be carried out as soon as practicable.
  • B. Transfer the oil to some other tank using fuel transfer pump,
  • C. Keep heating the oil to maintain a higher temperature
  • D. Circulate the oil in the same tank using the cargo pump
Answer: A — Ventilation to lower the concentration of vapor in the ullage space and in specific areas where vapors may accumulate should be carried out as soon as practicable.
H2S hazards in residual fuel tanks are mitigated by ventilating ullage spaces to disperse accumulated toxic vapours as soon as practicable prior to sampling, gauging, or tank work.

30. Inert gas is introduced to cargo tank to:

  • A. Lower the LEL of cargo vapor.
  • B. To make the cargo vapors a lean mixture of hydro carbons
  • C. To exclude oxygen and thus prevent fire or explosion.
  • D. Cool down the cargo
Answer: C — To exclude oxygen and thus prevent fire or explosion.
Inert gas (with low oxygen content <5% from the generator and <8% in the tank) is supplied to cargo tanks to displace oxygen and render the atmosphere non-flammable.

Set 5 — 30 OCTCO/OCTF exit exam questions with answers

1. What is Cargo inhibition?

  • A. All chemical cargo physical and chemical properties change. during transportation; to avoid this, certain inhibitors are added to the cargo
  • B. For some chemical cargoes. under heat and in presence of oxygen, their physical and Chemical properties change. To avoid this certain inhibitor are added to the cargo
  • C. Some chemical cargoes have some physical and chemical properties that change due to cold weather in presence of oxygen, to avoid this. Certain inhibitors are added to the cargo
  • D. Adding Inhibitors to a refined vegetable oil adds its market value as the inhibitor maintains its color
Answer: B — For some chemical cargoes. under heat and in presence of oxygen, their physical and Chemical properties change. To avoid this certain inhibitor are added to the cargo
Cargo inhibition involves adding specific chemical stabilizers/inhibitors to sensitive monomers (like styrene) to prevent self-polymerization or degradation under temperature and oxygen exposure.

2. Why are inhibitors added in the cargo?

  • A. Inhibitors are added by the ship staff before loading are Toxic. Inhibited cargoes often need oxygen hence should be carried in inerted tanks.
  • B. Inhibitors are added by the Terminal before loading are Toxic. Inhibited cargoes often need oxygen hence should not be carried in inerted tanks.
  • C. Inhibitors that are added by the Terminal before loading are Non-Toxic. Inhibited cargoes do not need oxygen and can be carried in inerted tanks.
  • D. Once the cargo is inhibited, its temperature is never a concern for cargo carriage
Answer: B — Inhibitors are added by the Terminal before loading are Toxic. Inhibited cargoes often need oxygen hence should not be carried in inerted tanks.
Certain chemical cargo inhibitors require dissolved oxygen to remain active; carrying these inhibited cargoes under total inerting without proper oxygen levels can cause premature inhibitor failure.

3. The main elements of peak safety performance are?

  • A. reducing the number of accidents to less than 5 % of the previous year's accidents
  • B. reducing the number of pollution incidents to less than 2 % of the previous year pollution incidents.
  • C. No operational incidents, no personal injuries and no harm to the environment.
  • D. Increasing vessel speed
Answer: C — No operational incidents, no personal injuries and no harm to the environment.
Peak safety performance in modern shipping targets zero operational incidents, zero occupational personal injuries, and zero environmental pollution.

4. Organizational safety value aims at:

  • A. < 2 incidents in a year
  • B. reduce incidents to less than 10 % of incidents in the previous year
  • C. Zero incident program
  • D. allow only one incident per year.
Answer: C — Zero incident program
A proactive organizational safety culture aims for continuous safety excellence through a zero-incident program.

5. What factor mainly affects Vapor cloud dilution rate?

  • A. Quantity of Spill
  • B. Weather conditions
  • C. Thermal inversion
  • D. diameter of the vapor cloud
Answer: B — Weather conditions
The rate of dispersion and dilution of a hazardous vapour cloud in the atmosphere is primarily governed by prevailing ambient weather conditions (wind speed, turbulence, atmospheric stability).

6. How is the Putrefaction process connected to Carbon Monoxide?

  • A. Putrefaction process generates obnoxious and toxic vapors
  • B. Putrefaction process depletes the oxygen in the tank due to chemical reaction
  • C. Putrefaction process generates obnoxious and toxic vapors and these depletes the oxygen in the tank due to chemical react ion
  • D. Purification occurs due to a decrease in tank temperature
Answer: B — Putrefaction process depletes the oxygen in the tank due to chemical reaction
Putrefaction of organic materials or vegetable oils depletes oxygen in the enclosed space through chemical decomposition and generates hazardous toxic gases.

7. Chemical cargo vapors can enter the human body due to:

  • A. Continuous working on deck.
  • B. Working i n the pump room
  • C. Inhalation, skin contact and also swallowing.
  • D. Improper use of proper PPE
Answer: C — Inhalation, skin contact and also swallowing.
Chemical cargo vapours and toxins can enter the human body via three primary exposure pathways: inhalation (respiratory tract), skin contact/absorption, and ingestion (swallowing).

8. Key Features and Measurement of an Effective Safety Culture; identify one statement that identifies an effective safety culture?

  • A. Recognition that all accidents are preventable and only usually occur following unsafe actions or a failure to follow established procedures
  • B. Individual seafarers assume responsibility for safety rather than relying on others to provide it
  • C. Through mutual respect, increasing confidence in the value of the safety culture results in a more effective Safety Management System
  • D. A safety management system that is always setting targets for continuous improvement, with a goal of zero accidents
Answer: D — A safety management system that is always setting targets for continuous improvement, with a goal of zero accidents
A core principle of an effective safety culture is the continuous drive of the safety management system toward continuous improvement with the ultimate goal of zero accidents.

9. Paraffinic, Paraffinic- Naphthenic and Aromatic Intermediate are the three classifications of?

  • A. Natural gas
  • B. Crude oil
  • C. Coal
  • D. Asphalt
Answer: B — Crude oil
Crude oils are broadly classified based on chemical composition into paraffinic, paraffinic-naphthenic, and aromatic/asphaltic intermediate bases.

10. Higher viscosity means?

  • A. Proper atomization of fuel
  • B. Rich atomization of fuel
  • C. Poor atomization of fuel
  • D. Easy pumping
Answer: C — Poor atomization of fuel
Higher viscosity fluids resist atomization and flow, leading to poor atomization and incomplete combustion in oil-burning systems unless preheated.

11. What is the sulfur content in natural gas of typical petroleum?

  • A. 0.20%
  • B. 0. 1 - 6%
  • C. 2 - 8%
  • D. 12 - 15%
Answer: A — 0.20%
Natural gas from typical petroleum reservoirs generally contains trace sulfur content of around 0.20% (or lower), whereas sour gas requires sweetening.

12. Vapor density of most of the chemical cargoes is?

  • A. Lighter than air
  • B. Heavier than air
  • C. Same as air density
  • D. None of these
Answer: B — Heavier than air
Most chemical and hydrocarbon cargo vapours are heavier than air (vapor density > 1.0), causing them to settle and accumulate in low-lying deck areas, scuppers, and bilges.

13. What is the effect of intermolecular forces on vapor pressure?

  • A. Relatively strong force will increase vapor pressure
  • B. Relatively strong force will decrease vapor pressure
  • C. Relatively weak force will decrease vapor pressure
  • D. Relatively weak force does not have any effect on vapor pressure
Answer: B — Relatively strong force will decrease vapor pressure
Stronger intermolecular attractive forces in a liquid hold molecules more tightly, resulting in lower vapour pressure and higher boiling points.

14. A gas venting system on a tanker that has gas lines in each tank connected to a common gas main running the full length of the ship is called:

  • A. A gas-main system
  • B. A common-main system
  • C. A vent-main system
  • D. An independent system
Answer: B — A common-main system
A common-main venting system connects individual tank branch lines into a continuous common gas main header running the full length of the cargo tank area.

15. Category Z noxious liquid substances from tank cleaning are deemed to present a hazard; find the correct statement.

  • A. Justify the prohibition of discharge into the marine environment
  • B. Justify a limitation on the quantity of discharge into the marine environment
  • C. Justify less stringent restrictions of discharge into the marine environment
  • D. None of the above
Answer: C — Justify less stringent restrictions of discharge into the marine environment
Under MARPOL Annex II, Category Z noxious liquid substances present a minor hazard to marine resources/human health, justifying less stringent discharge criteria than Categories X or Y.

16. Acidic solutions are formed in cargo tanks of tankers?

  • A. When Sulphur compounds in oil cargoes react with water
  • B. When Sulphur compounds in oil cargoes react with oxygen
  • C. When Sulphur compounds in oil cargoes react with hydrocarbon gas
  • D. When Sulphur compounds in oil cargoes react with chemicals
Answer: A — When Sulphur compounds in oil cargoes react with water
Acidic solutions form inside tanker cargo tanks and inert gas lines when sulphur oxides (SO2/SO3) or sulphur compounds react with condensed moisture/water.

17. What are closed operations?

  • A. Ballasting, loading or discharging operations carried out without opening ullage ports
  • B. To prevent the escape of hazardous vapor from tanks
  • C. Remote control of tank delivery valves
  • D. Remote control of inert gas entry into a tank
Answer: A — Ballasting, loading or discharging operations carried out without opening ullage ports
Closed cargo operations refer to loading, ballasting, ullaging, and discharging performed with all tank hatches, ullage ports, and access covers tightly closed to prevent hazardous vapour release.

18. The change in resistance of hot filament in tank scope is displayed as:

  • A. % Volume of oxygen
  • B. % Volume of inert gas
  • C. % Volume of hydrocarbon
  • D. % LEL
Answer: C — % Volume of hydrocarbon
The Tankscope (non-catalytic thermal conductivity gas meter) measures the concentration of hydrocarbon vapour in an inerted atmosphere over the range of 0 to 100% volume hydrocarbon.

19. The important series of hydrocarbons found in almost every petroleum mixture from any part of the world is?

  • A. Paraffin
  • B. Aromatic
  • C. Asphaltene
  • D. Napthine
Answer: B — Aromatic
Aromatic hydrocarbons (such as benzene, toluene, and xylene) are an important cyclic series of hydrocarbons present in almost all natural petroleum mixtures.

20. The content of cycloparaffins in petroleum may vary?

  • A. Up to 60%
  • B. Up to 70%
  • C. Up to 35%
  • D. Up to 50%
Answer: A — Up to 60%
Cycloparaffins (naphthenes) typically constitute up to 60% of the hydrocarbon content in various crude oil types.

21. Vapor pressure in cargo tanks is affected by:

  • A. type of cargo
  • B. density of cargo
  • C. temperature of cargo
  • D. inert gas
Answer: C — temperature of cargo
The saturated vapour pressure of a liquid in a closed cargo tank increases exponentially with increasing cargo temperature.

22. Sublimation is the phase transition of a substance:

  • A. From the liquid to the solid phase
  • B. From the solid to the liquid phase
  • C. From to the gas phase to the solid phase
  • D. From the solid to the gas phase
Answer: D — From the solid to the gas phase
Sublimation is the direct phase transition of a substance from the solid phase directly into the gas phase without passing through the liquid phase.

23. The most stable naphthenic hydrocarbons are the naphthene rings with?

  • A. Seven and Eight carbon atoms
  • B. Two and four carbon atoms
  • C. five and six carbon atoms
  • D. Four and seven car bon atoms
Answer: C — five and six carbon atoms
The most chemically stable naphthenic hydrocarbons are 5-membered (cyclopentane) and 6-membered (cyclohexane) saturated carbon rings due to low ring strain.

24. Static accumulator oils have an electrical conductance of less than?

  • A. 5 Pico Siemens per meter
  • B. 25 Pico Siemens per meter
  • C. 50 Pico Siemens per meter
  • D. 100 Pico Siemens per meter
Answer: C — 50 Pico Siemens per meter
Under ISGOTT, static accumulator petroleum oils are defined as liquids having an electrical conductivity of less than 50 picoSiemens per meter (pS/m).

25. Paraffins are fully saturated (no double bond). They remain unchanged over long periods of geological time and they are?

  • A. Unstable
  • B. Soluble
  • C. stable
  • D. Reactive
Answer: C — stable
Paraffins (alkanes) are fully saturated aliphatic hydrocarbons with single covalent bonds, rendering them chemically stable and unreactive under normal storage conditions.

26. Paraffins are pure hydrocarbons containing:

  • A. only hydrogen
  • B. only carbon
  • C. carbon and hydrogen
  • D. bromine
Answer: C — carbon and hydrogen
Paraffins (alkanes) are pure hydrocarbons composed solely of carbon and hydrogen atoms following the general chemical formula CnH2n+2.

27. Cargoes should not be loaded into a tank that is not specially for that duty if it exceeds normal atmospheric pressure at?

  • A. 60.0 Deg C (140 Deg F)
  • B. 15.6 Deg C (60 Deg F)
  • C. 25.0 Deg C (77 Deg F)
  • D. 37.8 Deg C (100 Deg F)
Answer: D — 37.8 Deg C (100 Deg F)
Cargoes exerting high vapour pressure must not be loaded into standard atmospheric tanks if the Reid Vapour Pressure exceeds atmospheric limits at 37.8°C (100°F).

28. Which category of NLS chemical in bulk poses maximum threat?

  • A. y
  • B. OS
  • C. X
  • D. Z
Answer: C — X
Under MARPOL Annex II, Category X noxious liquid substances present a major hazard to marine resources and human health, strictly prohibiting any operational discharge into the sea.

29. Cargo tank fill alarm indicator panels:

  • A. are normally fitted on the bridge and sometimes on deck
  • B. are normally fitted in the engine control room and sometimes on deck
  • C. are normally fitted on the bridge and sometimes in the engine control room
  • D. are normally fitted in the cargo control room and sometimes on deck
Answer: D — are normally fitted in the cargo control room and sometimes on deck
Cargo tank high-level and overfill alarm indicator panels are fitted in the Cargo Control Room (CCR) and audible/visual alarms are installed on deck for monitoring by watchkeepers.

30. Tank coating requirements developed by IMO are applicable to?

  • A. new crude oil tankers of 5000 GRT and above
  • B. new crude oil tankers of 5000 DWT and above
  • C. new crude oil tankers of 500 GRT and above
  • D. new crude oil tankers of 500 DWT and above
Answer: B — new crude oil tankers of 5000 DWT and above
IMO Performance Standard for Protective Coatings (PSPC) applies to dedicated seawater ballast tanks in all types of ships and double-side skin spaces of crude oil tankers of 5,000 DWT and above.

Set 6 — 30 OCTCO/OCTF exit exam questions with answers

1. The total capacity of all slop tanks on an oil tanker normally should be?

  • A. 1% of the total oil carrying capacity of ship
  • B. 2% of the total oil carrying capacity of ship
  • C. 3% of the total oil carrying capacity of ship
  • D. 4% of the total oil carrying capacity of ship
Answer: C — 3% of the total oil carrying capacity of ship
Under MARPOL Annex I, the total capacity of slop tanks on an oil tanker must normally not be less than 3% of the vessel's total oil cargo carrying capacity (or 2% for SBT tankers).

2. In chemical tankers the coding system used by the IBC Code for an independent tank is?

  • A. 1
  • B. 2
  • C. G
  • D. P
Answer: A — 1
Under the IBC Code tank type classification, an independent tank (not forming part of the ship's hull structure) is designated by the code 1.

3. Which of the following is cofferdam?

  • A. Chain locker
  • B. Pump room on an oil tanker
  • C. Deep tank
  • D. Slop tank on an oil tanker
Answer: B — Pump room on an oil tanker
On an oil tanker, the cargo pump room is a designated cofferdam/void space separating the cargo tank area from the engine room machinery spaces.

4. The purpose of a cofferdam between two compartments is to?

  • A. Store tools and equipment that are necessary for the adjacent compartments
  • B. Give access to the bulkhead for inspection and repairs when the tanks are full with liquid
  • C. Keep a reserve space if the capacity of either compartment needs to be increased
  • D. Prevent different liquids from the two tanks coming in contact in case of a leak
Answer: D — Prevent different liquids from the two tanks coming in contact in case of a leak
A cofferdam is an isolating void space between two bulkheads designed to prevent liquid or vapour from leaking directly between adjacent compartments (e.g. cargo tank and engine room).

5. Which pump must always be primed?

  • A. Centrifugal pump
  • B. Reciprocating pump
  • C. Rotary pump
  • D. Gear pump
Answer: A — Centrifugal pump
Centrifugal pumps cannot pump air or create suction lift from a dry condition; therefore, their casing and suction eye must always be primed with liquid before operation.

6. What does "VECS" stand for?

  • A. Vector control system
  • B. Vapor emission control system
  • C. Very economical control system
  • D. An arrangement for release of cargo vapor
Answer: B — Vapor emission control system
VECS stands for Vapour Emission Control System, which collects and returns displaced cargo vapours ashore during tanker loading.

7. The minimum safety during EGB soot blow must be carried out with?

  • A. The OOW & Masters consent avoid soot blow during the purging time
  • B. Any time excluding the dark night hours
  • C. At 12 hours interval
  • D. At 8 hrs. interval
Answer: A — The OOW & Masters consent avoid soot blow during the purging time
Exhaust Gas Boiler (EGB) soot blowing must only be carried out with the Master's and Officer of the Watch (OOW) consent, avoiding soot blowing during purging or adverse wind conditions.

8. Why is a warning sign displayed at the gangway or access point of a barge during cargo transfer?

  • A. To indicate any health risk if applicable
  • B. To keep visitors away from the barge-No smoking, no open lights, no visitors
  • C. To designate smoking areas
  • D. To indicate if the cargo is a marine pollutant
Answer: B — To keep visitors away from the barge-No smoking, no open lights, no visitors
Warning safety notices ('No Smoking, No Naked Lights, No Unauthorized Visitors') are posted at vessel gangways and barge access points to prevent potential ignition sources in the cargo area.

9. Oxygen deficiency will begin to cause problems to personnel, do you feel to measure the atmosphere before entering clean Tanker?

  • A. Not necessary for ballast tanks
  • B. Always necessary for ballast tanks
  • C. Not necessary if the tank is filled up twice and discharged at sea
  • D. Not necessary if the tank is ventilated by external fans
Answer: B — Always necessary for ballast tanks
Atmospheric testing for oxygen (>20.9%), flammable gases (0% LEL), and toxic vapours (0 ppm) is always mandatory before anyone enters any ballast tank or void space.

10. Which party is responsible for arranging the reducers or enlarger short pieces to the manifold?

  • A. The Cargo supplier
  • B. The Cargo Surveyors
  • C. The Ships Mooring crew
  • D. The tankers staff for the operation
Answer: A — The Cargo supplier
During tanker-terminal operations, the terminal/cargo supplier is responsible for providing and fitting the required manifold reducers or spool pieces to match the shore loading arms.

11. Very light gaseous molecules such as ______ are extracted at the well head?

  • A. Methane
  • B. Butane
  • C. Propane
  • D. None of these
Answer: A — Methane
Very light gaseous hydrocarbons, primarily Methane (C1), are extracted directly at the wellhead and processed as natural gas / LNG.

12. In the event of a pneumatic remote-control failure in the inert gas plant I/P and E/P controllers, during discharge _____?

  • A. The inert gas plant must be operational within one hour of failure and the discharging may continue for this time
  • B. The discharge must be immediately halted
  • C. The discharge rate must be reduced until the plant is repaired
  • D. The venting of IG is set to maintain a predetermined pressure and the discharge can continue manually
Answer: C — The discharge rate must be reduced until the plant is repaired
If pneumatic IG pressure control fails during cargo discharge, the cargo discharge pumping rate must be immediately reduced or managed to ensure tank pressure remains safely positive.

13. When the IG plant is shutdown, the IBC cooling water should be let on the scrubber for at least ____hour(s)?

  • A. 1
  • B. 2
  • C. 3
  • D. 4
Answer: C — 3
When shutting down the inert gas plant, cooling water to the scrubber tower must be kept running for at least 3 hours (or per manufacturer instructions) to wash away acidic deposits and cool the internal packing.

14. What are consequences of a high oxygen content alarm sound during normal operation?

  • A. The plant is shut down
  • B. The pressure control valve and the flue gas isolating valve will automatically close
  • C. The alarm in Ccr will sound loud and the plant will auto stop
  • D. The deck demand valve will automatically close. The atmosphere purge valve will open and the furnace presser control valve will regulate.
Answer: D — The deck demand valve will automatically close. The atmosphere purge valve will open and the furnace presser control valve will regulate.
When high oxygen content (>8%) is detected in the inert gas supply line, the deck demand isolating valve automatically trips shut and the atmospheric vent/purge valve opens to protect cargo tanks.

15. What are these types of tanker: -LR1 (large range 1)?

  • A. 25,000-49,999DWT
  • B. 50,000-79,999 DWT
  • C. 80,000-159,999 DWT
  • D. None Of the Above
Answer: B — 50,000-79,999 DWT
LR1 (Long Range 1) product/oil tankers range in deadweight size from 50,000 to 79,999 DWT.

16. The petroleum remaining after the removal of products such as methane is termed_______?

  • A. Crude oil
  • B. Diesel oil
  • C. HFO
  • D. None Of These
Answer: A — Crude oil
The complex mixture of liquid hydrocarbons remaining after light wellhead gases (methane, ethane) are separated is termed crude oil.

17. PROTECTION for acetylene & oxygen line flame arresters & N/R flow back valves are for?

  • A. Carrying out gas welding & acetylene gas cutting work
  • B. Protection of personnel from high temp.
  • C. Preventing sparks from entering a tank or vent opening
  • D. Fire fighting
Answer: A — Carrying out gas welding & acetylene gas cutting work
Flashback arresters and non-return check valves on oxy-acetylene lines are critical safety devices preventing flame propagation back into the gas supply cylinders during gas welding/cutting.

18. In case of P/V valve for one tank is not working and the tank pressure is rising, what immediate actions are necessary usually set to follow?

  • A. Abort filling that individual tank
  • B. Try to open the valve manually
  • C. Isolate the line and change the valve from vessels tested spare
  • D. Follow all the procedures (A) + (B) &(C)
Answer: D — Follow all the procedures (A) + (B) &(C)
If an individual tank P/V valve malfunctions and tank pressure rises abnormally, the crew should abort filling that tank, verify/free the valve manually if safe, and replace it with a tested vessel spare.

19. Which topic is not required to be discussed at the pre- transfer conference?

  • A. Estimated time of finishing cargo
  • B. Details of transfer and receiving system
  • C. Emergency shutdown procedures
  • D. Identity of the product to be transferred
Answer: A — Estimated time of finishing cargo
While transfer rates, shutdown signals, and product safety details are mandatory items in the pre-transfer conference, estimated cargo completion time is an operational estimate rather than a safety checklist prerequisite.

20. Examples of inorganic chemicals such as:

  • A. Sulphuric acid
  • B. Phosphoric acid
  • C. Nitric acid
  • D. All of the above
Answer: D — All of the above
Common inorganic liquid bulk chemicals transported on chemical tankers include mineral acids such as sulphuric acid (H2SO4), phosphoric acid (H3PO4), and nitric acid (HNO3).

21. Clean ballast is normally______?

  • A. Ballast water loaded directly into a cargo tank after discharge
  • B. Ballast water into cargo tanks which have been washed crude oil
  • C. Ballast water loaded into cargo tanks which have been crude oil and water washed
  • D. Ballast water loaded in designated tanks used only for that purpose
Answer: C — Ballast water loaded into cargo tanks which have been crude oil and water washed
Clean ballast under MARPOL Annex I refers to ballast water carried in a cargo tank which has been thoroughly crude-oil-washed and water-washed such that effluent shows no visible oil trace.

22. During loading operation ullage and temp measuring equipment is showing low battery which place can we replace battery?

  • A. Can be replaced on tank area
  • B. Can be replaced near manifold area
  • C. Can be replaced at pump room entrance
  • D. Can be replaced only with indoor accommodation
Answer: D — Can be replaced only with indoor accommodation
Portable electronic measuring devices (MMC/UTI tapes) must only have their batteries changed inside safe, non-hazardous areas within the accommodation, never in hazardous deck zones.

23. Vessels in clean service normally do not have or need heater coils as the viscosity of the clean product is low enough to permit easy pumping at atmospheric temps.

  • A. Applies to all clean petroleum products (CPP)
  • B. With the exception of some lube oils & special vegetable oils
  • C. Applies to all chemicals
  • D. Applies to all condensates
Answer: B — With the exception of some lube oils & special vegetable oils
Clean petroleum products (CPP) have low viscosity and do not require heating coils, with the exception of certain heavy lubricating base oils and high-pour-point vegetable oils.

24. The foam system is operated from the _____room?

  • A. CCR
  • B. ECR
  • C. FGFC
  • D. All the above
Answer: C — FGFC
Fixed deck foam fire-extinguishing systems are operated from the Fire Gun / Foam Control (FGFC) central emergency station or designated foam room outside the cargo area.

25. MARPOL Annex VI applies:

  • A. Only the ships that fly the flag of a state that is party to MARPOL annex VI
  • B. Only to ships that visit ports of a state that is party to MARPOL annex VI
  • C. To ship with both of the above
  • D. All ships irrespective of flag or port state control requirements
Answer: C — To ship with both of the above
MARPOL Annex VI regulations apply to all ships flying the flag of a Party state, as well as ships operating in or visiting the ports and territorial waters of a State Party under Port State Control.

26. Inert gas after leaving the demister will consist of the following?

  • A. Oxygen less than 5%
  • B. SO2 less than 2.0%
  • C. Water vapor 1%
  • D. Both A & B
Answer: D — Both A & B
Properly scrubbed and demisted inert flue gas leaving the scrubber tower typically contains less than 5% oxygen by volume and negligible sulfur dioxide (<20-50 ppm).

27. How much volume of air needs to be changed in pump room?

  • A. 10 vol/hr.
  • B. 25 vol/hr.
  • C. 20 vol/hr.
  • D. 15 vol/hr.
Answer: C — 20 vol/hr.
SOLAS regulations require the mechanical ventilation system in cargo pump rooms to provide a minimum extraction rate of at least 20 air changes per hour based on total room volume.

28. Fixed foam monitors having a operating capacity_____L/min?

  • A. 1250
  • B. 1450
  • C. 1150
  • D. 1650
Answer: A — 1250
Fixed deck foam monitors on tankers are sized to deliver a standard minimum operational discharge rate of 1,250 litres per minute to effectively cover cargo manifold and deck areas.

29. In tankers, the central equipment is available either for installation in _____locations.

  • A. Hazardous
  • B. Non-hazardous
  • C. Under – pressurized
  • D. All of the above
Answer: B — Non-hazardous
Central control equipment, computers, and non-intrinsically safe electrical monitoring consoles on tankers are installed in designated non-hazardous spaces (such as the CCR or Wheelhouse).

30. The physical data of a liquid chemical can be found on_____?

  • A. MSDS (material safety data sheets)
  • B. The Information supplied by the manufacturer
  • C. ICS cargo data sheet
  • D. All of these a), b) & c)
Answer: D — All of these a), b) & c)
Comprehensive physical and chemical safety data for bulk liquid cargoes is obtained from the Material Safety Data Sheet (MSDS), manufacturer product guides, and ICS Cargo Data Sheets.

Set 7 — 30 OCTCO/OCTF exit exam questions with answers

1. Gas testing onboard tankers can be carried out with the following equipment onboard?

  • A. MMC
  • B. Thermometer
  • C. Gas instrument
  • D. Sample
Answer: C — Gas instrument
Atmospheric gas testing on board tankers is conducted using calibrated multi-gas instruments, oxygen analyzers, combustible gas indicators (explosimeters), and toxic gas detectors.

2. What % of air is made up by oxygen?

  • A. 78%
  • B. 21%
  • C. 100%
  • D. 4%
Answer: B — 21%
Standard atmospheric ambient air is composed of approximately 20.9% (approx. 21%) oxygen, 78% nitrogen, and 1% argon and other trace gases.

3. Does the muster list and the emergency instruction contain information relevant only to the deck officers?

  • A. Yes
  • B. No
  • C. No, all crew members and other personnel onboard
  • D. No relevant to all offices
Answer: C — No, all crew members and other personnel onboard
The shipboard muster list and emergency station bill specify emergency duties and muster stations for all crew members and personnel on board.

4. COW operation is conducted during?

  • A. Discharging operation
  • B. Tank cleaning operation
  • C. Loading operation
  • D. Gas freeing operation
Answer: A — Discharging operation
Crude Oil Washing (COW) is carried out concurrently during cargo discharge operations using the liquid crude cargo as the washing medium under an inert atmosphere.

5. Before cargo operations start the master should establish liaison between the ship and______?

  • A. The terminal
  • B. The flag state administration
  • C. The port authority
  • D. The arbor controls
Answer: A — The terminal
Prior to starting any cargo handling operations, the ship Master/Chief Officer must establish clear communication and operational liaison with the terminal representative.

6. If at sea the inert gas low pressure alarm is activated it may be necessary to conduct____?

  • A. Cargo heating operations to raise the pressure
  • B. Cargo transfer operation to raise the pressure
  • C. Inert gas topping up operations
  • D. Reduce engine speed to allow safe ingress of atmospheric air
Answer: C — Inert gas topping up operations
If the inert gas low-pressure alarm activates during a loaded sea passage, the crew must initiate inert gas topping-up operations to restore positive pressure in the cargo tanks.

7. When oil temperature rises, the volume _______?

  • A. Varies
  • B. Reduces
  • C. Increases
  • D. Remain the same
Answer: C — Increases
When the temperature of an oil cargo increases, the liquid expands in volume and its density correspondingly decreases.

8. An important publication required to be approved by the flag state and carried onboard chemical tankers?

  • A. The procedure and arrangements manual
  • B. The operation manual
  • C. The arrangements manual
  • D. The procedures manual
Answer: A — The procedure and arrangements manual
Under MARPOL Annex II, every chemical tanker must carry an approved Procedures and Arrangements (P&A) Manual describing physical equipment, washing procedures, and discharge arrangements.

9. The low velocity fog applicator used in conjunction with the all-purpose firefighting nozzle, should always be_______________?

  • A. Stored in the rack when not in actual use
  • B. Attached to the nozzle by the chain
  • C. Coated with heavy grease to prevent corrosion
  • D. Left in place in the all –purpose nozzle
Answer: A — Stored in the rack when not in actual use
Low-velocity fog applicators used with dual-purpose firefighting nozzles should be safely stowed in their dedicated storage racks when not in active firefighting use.

10. Which safety device is fitted on the inert gas scrubber tower to monitor the efficient operation of the plant?

  • A. The inert gas low flow alarm
  • B. The scrubber tower high level alarm
  • C. The scrubber tower low pressure & non flow alarm of cooling tower
  • D. Both (B) & (C)
Answer: D — Both (B) & (C)
The inert gas scrubber tower is protected by safety interlocks and alarms for high water level (to prevent flooding the flue gas line) and low cooling water flow/pressure.

11. In the event of cargo spillage, which of following would be informed first?

  • A. The clean-up contractor
  • B. The agent
  • C. The ship owner
  • D. The port authority
Answer: D — The port authority
In the event of an accidental cargo spillage during port operations, the port authority and coast guard/coastal state administration must be notified immediately as per the SOPEP/SMPEP.

12. One of the requirements for the crude oil washing on tankers is that an inert gas system be fitted, according to regulations supply of an inert gas system can be have portable connection to which space other than cargo tank?

  • A. Every cargo tanks
  • B. Every cargo and slop tank and cofferdam
  • C. Every cargo and slop tank
  • D. Every cargo tank, slop tank, cofferdam and ramp space
Answer: C — Every cargo and slop tank
Under SOLAS regulations, inert gas supply lines are permanently connected to all cargo and slop tanks to maintain positive inert overpressure at all times.

13. High IG temperature trip is about___?

  • A. 55C
  • B. 65C
  • C. 85C
  • D. 75C
Answer: D — 75C
The high inert gas temperature trip on an IGS plant automatically shuts down the gas supply if the gas leaving the scrubber exceeds 75°C to protect downstream equipment and deck seals.

14. The flammable range of different chemicals may be ___?

  • A. Always the same
  • B. The same
  • C. Often different
  • D. Always different
Answer: D — Always different
Different chemical and hydrocarbon products have widely differing lower and upper explosive limits (flammable ranges) depending on their molecular structure and volatility.

15. The apparatus consists of double opposed nozzles which rotate slowly about their horizontal and vertical axis and project two streams of water through all possible angles against all inside surfaces of the space being cleaned.

  • A. Crude oil washing machines
  • B. Butterworth tank cleaning machine
  • C. Manually operated deck tube nozzle machine
  • D. All of the above (A) (B) (C) or combinations of attachment
Answer: B — Butterworth tank cleaning machine
The Butterworth tank cleaning machine consists of dual or multiple rotating nozzles driven by water pressure that revolve through vertical and horizontal planes to wash all internal tank bulkheads.

16. Pyrophoric iron sulphide is formed:

  • A. In the presence of oxygen
  • B. In presence of H2S
  • C. When rust is formed in tanks
  • D. All of the above
Answer: D — All of the above
Pyrophoric iron sulphide forms inside crude tanks when iron rust (iron oxide) reacts with hydrogen sulphide (H2S) in an oxygen-depleted atmosphere.

17. It is the lowest liquid temperature at which the small flame initiates a flash of flame across the surface of the liquid, there by indicating presence of flammable gas above the liquid?

  • A. Pour point
  • B. Flash point
  • C. Cloud point
  • D. None of the above
Answer: B — Flash point
Flash point is the lowest temperature at which a liquid gives off sufficient flammable vapour to ignite momentarily (flash) in the presence of an external ignition source.

18. What does ODME mean?

  • A. Oil detecting – master evaluating
  • B. Over board detecting measure equipment
  • C. Oil detection measure equipment
  • D. Oil discharge monitoring equipment
Answer: D — Oil discharge monitoring equipment
ODME stands for Oil Discharge Monitoring and Control Equipment, which continuously monitors and controls oil content in overboard discharges under MARPOL Annex I.

19. Which of the following is compulsory on ships fitted with inert gas?

  • A. No smoking is allowed in any place at all on the vessel
  • B. an entry permit is required each time a person enters the pump room for any reason
  • C. Notice is to be placed at entrance as required NO ENTRANCE WITHOUT PERMISSION OF RESPONSIBLE PERSON (C / O) inert gas
  • D. Three (3) breathing apparatus sets with spare bottles and a refilling compressor Is fitted in the forecastle
Answer: C — Notice is to be placed at entrance as required NO ENTRANCE WITHOUT PERMISSION OF RESPONSIBLE PERSON (C / O) inert gas
On tankers fitted with inert gas systems, prominent warning notices stating 'NO ENTRY WITHOUT PERMISSION OF RESPONSIBLE OFFICER' must be posted at entrances to inerted spaces.

20. All VLCC normally has cargo tank heating arrangement as?

  • A. Heating steam arrangement in the individual tanks by steam circulation
  • B. Deck heaters electrically heated for circulation through heaters
  • C. Deck steam heater heated by steam circulation
  • D. None of the above
Answer: C — Deck steam heater heated by steam circulation
Large crude carriers (VLCCs) utilize steam deck heaters or internal steam heating coils to maintain crude oil at the required carriage and discharge pumping temperatures.

21. ____ is considered as best material for IG blower impellers?

  • A. Chromium
  • B. Steel
  • C. Titanium
  • D. Aluminum
Answer: D — Aluminum
Inert gas blower impellers are typically manufactured from aluminum alloys or non-ferrous materials to prevent mechanical frictional sparking in case of casing contact.

22. IG blowers are to be fitted with inlet and outlet valves in gas line with ___seats?

  • A. Copper
  • B. Aluminum
  • C. Leather
  • D. Rubber
Answer: D — Rubber
Inert gas blower isolating valves in flue gas lines are fitted with resilient rubber or elastomer seats to provide a gas-tight seal against corrosive flue gases.

23. There is an isolated fire on the poop deck, where should the master take control from?

  • A. The ship's office
  • B. The emergency headquarters
  • C. The incident sites
  • D. The bridge
Answer: D — The bridge
In the event of an emergency or poop deck fire, the Master commands and coordinates overall shipboard emergency response from the Bridge (Emergency Command Center).

24. When starting a stripping operation in a hydraulically operated centrifugal cargo oil pump system the following are the right path to follow?

  • A. Use a stripping vacuum system
  • B. The cargo wells are designed to carry out self-stripping
  • C. Use a separate stripping pump
  • D. All of the above as the system and attachment deemed fit
Answer: B — The cargo wells are designed to carry out self-stripping
Modern submerged centrifugal cargo pumping systems (such as Framo) utilize self-stripping wells and integrated stripping valves to drain tanks without requiring separate reciprocating stripping pumps.

25. The IBC code defines ___ types of chemical tankers?

  • A. 2
  • B. 3
  • C. 4
  • D. 5
Answer: B — 3
The IBC Code categorizes chemical tankers into three distinct ship types (Type 1, Type 2, and Type 3) based on the degree of hazard and damage survival capability required.

26. At which level will the slop system high level alarm sound?

  • A. 97%
  • B. 96%
  • C. 98%
  • D. 95%
Answer: D — 95%
Independent cargo and slop tank high-level alarms on tankers are set to activate audibly and visually when the liquid level reaches 95% volume capacity.

27. When operating with a negative suction head which of this type of pump is the best choice?

  • A. Reciprocating
  • B. Rotary
  • C. Gear
  • D. Centrifugal
Answer: A — Reciprocating
Positive-displacement reciprocating pumps create positive suction lift and are best suited for operating with a negative suction head or high vacuum conditions.

28. Loading through the pump discharge and recirculation line initially is _____?

  • A. Permissible
  • B. Done to increase the loading rate.
  • C. Normally the approved way to load all the cargo & slop tanks
  • D. To be avoided.
Answer: D — To be avoided.
Loading cargo initially through pump discharge and recirculation lines must be avoided to minimize splashing, turbulence, and static electricity generation.

29. When should employees be informed of the fire hazards to which they are exposed at work?

  • A. Upon the initial assignment
  • B. Within two days of the initial assignment
  • C. Within 30 days of the initial assignment
  • D. Within 90 days of the initial assignment
Answer: A — Upon the initial assignment
Occupational safety standards require all seafarers and terminal personnel to be informed of specific workplace fire hazards upon their initial assignment or onboarding.

30. A designated area within definite limits which has been accurately surveyed for clearance of sea bottom and submerged obstacles to a minimum indicated depth of water?

  • A. Designated routes
  • B. Safe shipping routes
  • C. Safe slop discharge routes
  • D. Deep water route
Answer: D — Deep water route
A deep-water route is a designated maritime routing measure accurately surveyed for clearance of the sea bottom and submerged obstacles for deep-draft vessels.

Set 8 — 30 OCTCO/OCTF exit exam questions with answers

1. The groups of alcohols and carbohydrates includes products which may be produced by fermentation, such as?

  • A. Liquor
  • B. Wine
  • C. Mollasses
  • D. None of these
Answer: B — Wine
Fermentation of organic sugars and starches produces alcohols (ethanol) and fermented beverages such as wine and spirits.

2. To discharge the last amount of cargo ashore, the stripping pump through the small diameter line is used from cargo tanks. Where does this small diameter line come from in the pump room ?

  • A. From the individual stripping line to the stripping pump.
  • B. From the tank suction line to the Main cargo oil pump.
  • C. From the cargo pump suction pipe line to the stripping pump.
  • D. From the cargo pump discharge line to the stripping pump.
Answer: D — From the cargo pump discharge line to the stripping pump.
The small-diameter MARPOL stripping line on an oil tanker connects the cargo pump discharge manifold to the shore connection to discharge the final liquid residue from cargo lines.

3. The term solubility refers to the ability to mix with _________?

  • A. Oil
  • B. Air
  • C. Water
  • D. other liquids
Answer: D — other liquids
Solubility is the chemical property describing the ability of a substance to dissolve and form a homogeneous mixture with another liquid or solvent.

4. Fixed foam monitors having a maximum capacity of _____ L/min?

  • A. 4400
  • B. 5500
  • C. 6600
  • D. 7700
Answer: D — 7700
Large fixed deck foam monitors installed on supertankers can have a maximum discharge capacity of up to 7,700 litres per minute for rapid deck fire suppression.

5. Cargo tanks are not ____ with IG before gas freeing then the concentration of atmosphere will pass through flammable range?

  • A. Crude oil washed
  • B. Purged
  • C. Tank cleaning
  • D. Re-inerting
Answer: B — Purged
Before gas freeing cargo tanks with fresh air, tanks containing hydrocarbon vapours must first be purged with inert gas until the hydrocarbon level is below the critical dilution line.

6. In scrubber _____ is readily absorbed by water?

  • A. SO2
  • B. SO3
  • C. SO4
  • D. Sox
Answer: A — SO2
In the inert gas scrubber tower, sulfur dioxide (SO2) in the flue gas is readily dissolved and absorbed by the alkaline seawater spray.

7. Inert gas system has scrubber tower in a flue gas from boiler flue gas type of system. What is the arrangement for a separately fired inert gas Generator?

  • A. The IG Generator also has scrubber tower combined with the furnace.
  • B. The IG Generator can also have a separate scrubber tower.
  • C. The separately fired IG Generator does not have a scrubber tower.
  • D. Conditions (A) and (C) are suitable.
Answer: A — The IG Generator also has scrubber tower combined with the furnace.
In separately fired inert gas generators (IGGs), the combustion chamber/furnace and the cooling/washing scrubber tower are integrated into a compact combined vertical unit.

8. Why CO2 is not used as an inert gas?

  • A. More denser
  • B. Have more conductivity
  • C. Have intense electro-static field
  • D. None of the above
Answer: C — Have intense electro-static field
Pure CO2 is not used for bulk tanker inerting because rapid expansion from high pressure generates intense electrostatic charges and sparks in flammable atmospheres.

9. Submerged cargo pumps cofferdam leakage is tested by the following intervals?

  • A. Every 6 months
  • B. Every 12 months
  • C. Every month
  • D. Every monthly & suitably after every operation of discharge/ballasting.
Answer: D — Every monthly & suitably after every operation of discharge/ballasting.
Submerged hydraulically driven cargo pump cofferdams must be purged and tested for seal leakage monthly and routinely after every cargo discharge or ballasting operation.

10. Who should tank cleaning operations be supervised by?

  • A. Shore representative
  • B. Pump man
  • C. Deck Officer
  • D. Responsible Officer
Answer: D — Responsible Officer
Tank cleaning and gas freeing operations must always be directly supervised by a qualified and designated Responsible Officer (Chief Officer).

11. With reference to liquefied gas operation, what is the term “rollover” used to describe?

  • A. When two or more stratified layers of different density LNG in the same tank suddenly mix together causing
  • B. Vapor pockets forming at the bottom of a half-filled tank
  • C. Custody transfer at the terminal
  • D. Moving LNG from one tank to another
Answer: A — When two or more stratified layers of different density LNG in the same tank suddenly mix together causing
Rollover in liquefied gas tankers refers to the sudden spontaneous mixing of stratified LNG layers of different densities, resulting in rapid boil-off vapour release.

12. What does code R stand in ship shore safety checklist?

  • A. Remarks
  • B. Request
  • C. Require
  • D. Re-checked
Answer: D — Re-checked
In the Ship/Shore Safety Checklist (SSSCL), the code 'R' indicates items that require periodic re-checking and logging at agreed time intervals throughout cargo operations.

13. Black oils are generally?

  • A. Static accumulators
  • B. Static non- accumulators
  • C. Both
  • D. None of the above
Answer: B — Static non- accumulators
Black oils (such as crude oils and heavy fuel oils) contain natural antistatic impurities and asphaltic components, making them static non-accumulators.

14. The gas regulating valve should be opened very slowly in order to avoid:

  • A. Back flow gas
  • B. Water carries over
  • C. Noise
  • D. Vibrations
Answer: A — Back flow gas
The inert gas regulating valve must be opened very slowly to prevent sudden pressure surges, backflow of gas, or water carry-over from the deck seal.

15. In crude oil tankers, the gas detectors installed should be?

  • A. Correct electrical classification
  • B. Weather proof
  • C. Corrosion resistant
  • D. All of the above
Answer: D — All of the above
Gas detection sensors and sampling units installed on crude oil tankers must have certified explosion-proof electrical ratings, weatherproof enclosures, and corrosion-resistant materials.

16. If the flash point of an oil cargo is 58°C, it is said to be?

  • A. Volatile
  • B. Non-volatile
  • C. Toxic
  • D. None of the above
Answer: A — Volatile
According to ISGOTT, petroleum having a closed-cup flashpoint below 60°C (such as 58°C) is classified as volatile petroleum.

17. Which is the basic safety device fitted on the deck inert gas line to monitor the supply condition of the inerted tanks and pipelines of supply of gas?

  • A. The inert gas low pressure alarm
  • B. The inert gas high temperature alarm
  • C. The inert gas low flow alarm
  • D. All the above (A), (B) and (C)
Answer: D — All the above (A), (B) and (C)
Basic safety monitoring devices fitted on the deck inert gas line include low-pressure alarms, high-temperature alarms, and low-flow alarms to safeguard tank integrity.

18. Which of these is a positive displacement pump?

  • A. Gear
  • B. Reciprocating
  • C. None of the above
  • D. Both (A) and (B)
Answer: D — Both (A) and (B)
Both gear pumps and reciprocating piston pumps operate by trapping fixed volumes of fluid and displacing it mechanically, making them positive displacement pumps.

19. What is the purpose of a “part flow system” installed on some oil tankers?

  • A. The Part Flow system makes it possible to discharge dirty ballast below the water line on older tankers.
  • B. The Part Flow system makes it possible to observe the discharge visually for oil content, on older tankers with discharge below the waterline.
  • C. The Part Flow system makes it possible to observe the discharge visually for oil content, even in darkness.
  • D. The Part Flow system makes it possible to measure the oil content, even if the Oil Discharge Monitoring Equipment is not working.
Answer: B — The Part Flow system makes it possible to observe the discharge visually for oil content, on older tankers with discharge below the waterline.
A part-flow system allows visual inspection of effluent discharged through below-waterline overboard lines on older tankers to detect any oil contamination.

20. Who should attend during connection of cargo oil transfer arms/hoses?

  • A. Pump man
  • B. Responsible deck officer
  • C. Able Seaman
  • D. Bosun
Answer: B — Responsible deck officer
Connecting and disconnecting cargo transfer arms, hoses, and manifolds must be directly supervised by a qualified, responsible deck officer.

21. During cargo operations, a wind blowing may ____?

  • A. Lower the temperature of the oil cargo
  • B. Form eddies containing petroleum vapor
  • C. Increase air pressure in a cargo tank
  • D. Decrease air pressure in a cargo tank
Answer: B — Form eddies containing petroleum vapor
During cargo loading, ambient wind blowing across the deck structure can create turbulent aerodynamic eddies that trap and concentrate flammable petroleum vapours.

22. In oil tankers, there are __ foam boxes on the cargo deck?

  • A. Two
  • B. Three
  • C. Four
  • D. Five
Answer: A — Two
On oil tankers, two dedicated foam boxes (hose/nozzle stations) are positioned on the cargo deck for rapid local foam application.

23. In IG system, ideally the blower casing should be ____ split with split bearings?

  • A. Horizontally
  • B. Vertically
  • C. Angularly
  • D. None of the above
Answer: B — Vertically
To allow easy maintenance, inspection, and impeller overhaul without dismantling ductwork, inert gas blower casings are ideally vertically split.

24. Before arriving in a port where it is intended to crude oil wash the tank washing system should be pressure tested to ____?

  • A. 150% of the working pressure
  • B. 125% of the normal working pressure
  • C. 75% of the normal working pressure
  • D. The normal working pressure
Answer: D — The normal working pressure
Before arriving in port for crude oil washing (COW), the entire tank washing piping system must be pressure tested to its normal working pressure to verify tightness.

25. LOT is defined as both a procedure and a practice?

  • A. Load on Top
  • B. Load on tanks
  • C. Load on Transverse
  • D. Load on Table
Answer: A — Load on Top
LOT stands for Load on Top, an operational oil retention procedure where new cargo is loaded directly on top of settled, decanted slop residues in compliance with MARPOL.

26. The minimum oxygen required for combustion?

  • A. 5%
  • B. 16%
  • C. 8%
  • D. 21%
Answer: B — 16%
Combustion of typical hydrocarbon vapours cannot be sustained when the oxygen concentration in the mixture falls below approximately 11% by volume (16% being the minimum required for open free-burning flames in air).

27. What are consequences of a ballast tank vent not working during deballasting operation?

  • A. The tank de pressurization and denting of side plates.
  • B. The tanks taking in cargo vapors during loading operation.
  • C. The cargo tank alteration of ullage are taking place.
  • D. Combination of all three a,b,c
Answer: A — The tank de pressurization and denting of side plates.
If a ballast tank air vent / vacuum valve fails during high-rate deballasting, internal vacuum can cause tank depressurization and severe structural buckling or denting of side shell plates.

28. Type 1 ship is a chemical tanker intended to transport chapter 17 of the IBC code product with very severe environmental and safety hazards which require maximum preventive measure to preclude an escape of such cargo.

  • A. False
  • B. True
  • C. High concentration of acid and organic compounds
  • D. Both(b)and(c)
Answer: D — Both(b)and(c)
Under the IBC Code, a Type 1 chemical tanker is designed to transport products presenting the most severe environmental and safety hazards, requiring maximum preventive containment measures.

29. A vessel is fitted with a sample locker or spill containment locker in the amidships, what is the general arrangement for firefighting of that compartment.

  • A. Foam applicator equipment.
  • B. Sprinkler system from the fire main
  • C. Portable extinguishers situated outside the compartment.
  • D. Any one of (A)or (C) in addition to (B)
Answer: D — Any one of (A)or (C) in addition to (B)
Fire protection for deck sample lockers and spill containment stores typically includes water sprinkler systems from the fire main or portable fire extinguishers situated adjacent to the compartment.

30. The inert gas leaving the demister is saturated with?

  • A. 90%RH
  • B. 80%RH
  • C. 100%RH
  • D. 60%RH
Answer: D — 60%RH
Inert gas leaving the scrubber demister is fully saturated with water vapour at 100% relative humidity before entering the deck distribution pipeline.

Set 9 — 12 OCTCO/OCTF exit exam questions with answers

1. In IG the mass of the water vapor contained in a given volume of saturated gas depends on the.........of the gas?

  • A. temperature
  • B. color
  • C. volume
  • D. velocity
Answer: A — temperature
In an inert gas system, the mass of water vapour held in a saturated gas volume is directly dependent on the temperature of the gas.

2. Which of the following is a safety consideration when dealing with liquefied gas?

  • A. its corrosive
  • B. it's cold
  • C. it's cacogenic
  • D. its caustic
Answer: B — it's cold
A primary safety consideration when handling liquefied gas cargoes is cryogenic temperature (-162°C for LNG), which causes severe cryogenic burns and brittle fracture of ordinary ship steel.

3. Before entry into a cargo tank which has contained a petroleum product.........

  • A. adjacent tanks must be empty
  • B. the tank must be filled with fresh water and emptied
  • C. static electricity must be measured
  • D. the tank must be tested for a sufficient amount of oxygen
Answer: D — the tank must be tested for a sufficient amount of oxygen
Prior to entering any enclosed cargo tank, the atmosphere must be rigorously tested and confirmed to have at least 20.9% oxygen, 0% LEL flammable gas, and zero toxic vapours.

4. The blower casing is of ...... material?

  • A. highly water resistant
  • B. corrosion resistant
  • C. both a and b
  • D. none of the above
Answer: C — both a and b
Inert gas blower casings are constructed from corrosion-resistant and water-resistant materials to withstand acidic moisture and soot particles present in scrubbed flue gas.

5. This valve is used in conjunction with closed and restricted measurement equipment to allow measurement in ship tanks that are closed to the atmosphere. Once a portable measurement unit (PMU) is attached to the VCV, the valve is opened and the PMU probe is dropped into the tank to perform the required measurement.

  • A. PMU point
  • B. measurement valve
  • C. Both (A) and (B)
  • D. vapor control valve (VCV)
Answer: D — vapor control valve (VCV)
A Vapour Control Valve (VCV) is installed on closed gauging standpipes to allow portable UTI/PMU gauging probes to enter sealed tanks without releasing hazardous cargo vapour.

6. Which of the following describes a liquefied gas?

  • A. a liquid that needs to be stored at absolute zero to prevent it from becoming gaseous.
  • B. a gas that is mixed with another substance that causes it to liquefy
  • C. a substance that at normal temperature and pressure would be a gas
  • D. a liquid that is required to be heated above normal ambient temperature to make it from a gas
Answer: C — a substance that at normal temperature and pressure would be a gas
A liquefied gas is defined as a substance that exists as a gas at normal atmospheric ambient temperature and pressure, but is maintained in a liquid state by refrigeration, pressure, or both.

7. As well as chemical what may chemical tankers also be used to transport.......

  • A. waste products
  • B. other liquid products
  • C. nuclear waste
  • D. bulk acids
Answer: B — other liquid products
In addition to industrial chemicals, chemical tankers are also certified to transport other bulk liquids such as vegetable oils, animal fats, and clean petroleum products.

8. The IG blower ........introduced pressure fluctuations in inert gas demand.

  • A. must not
  • B. should
  • C. may or may not
  • D. none of the above
Answer: A — must not
The inert gas blower must maintain steady discharge without introducing severe pressure pulsations into the cargo tank inerting network.

9. Are all pumps and blowers shut down during the emergency shut down procedure of a shipboard inert gas system?

  • A. no, the sea water pumps and the blowers are still running
  • B. no, the scrubber sea water pumps are still running
  • C. no, sea water cooling of deck seal running
  • D. yes, all is shut down
Answer: C — no, sea water cooling of deck seal running
During an emergency shutdown (ESD) of the inert gas system, the continuous seawater cooling and sealing flow to the deck water seal must remain operational to prevent backflow.

10. The draft reading at the middle of the ship markings, this draft can and often does, differ from the mean draft due to hogging or sagging?

  • A. mean draft
  • B. moulded draft
  • C. midship draft
  • D. none of the above
Answer: C — midship draft
The draft reading taken at the midship draft marks indicates the midship draft, which may differ from the mean draft due to hull hogging or sagging deflection.

11. Mast riser fire doesn't normally occur during?

  • A. purging
  • B. discharging
  • C. loading
  • D. purging inert gas pressure during normal passage
Answer: B — discharging
Mast riser fires do not normally occur during cargo discharging because air/inert gas is flowing into tanks or tank pressure is negative/neutral rather than venting high-velocity flammable vapour.

12. What is the term for filling tanks with nitrogen, or similar liquid or gas to prevent cargo contact with the atmosphere?

  • A. covering
  • B. padding
  • C. blanketing
  • D. inerting
Answer: B — padding
Padding is the term used to describe filling the ullage space of a cargo tank with an inert gas or liquid barrier (such as nitrogen) to prevent the cargo from contacting moisture or air.

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