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LGTCO/LGTF exit exam questions and answers — Set 2

Set 2 of the Liquefied Gas Tanker Cargo Operations (LGTCO/LGTF) exit exam bank — 30 of 159 questions, 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 2 — 30 LGTCO/LGTF exit exam questions with answers

1. What is the role of Nitrogen padding in gas shipping?

  • A. Clean deck
  • B. Warm up cargo
  • C. Increase density
  • D. Maintain positive dry inert gas pressure over cargo or insulation spaces
Answer: D — Maintain positive dry inert gas pressure over cargo or insulation spaces
Dry Nitrogen padding prevents moisture ingress and eliminates flammable atmospheres.

2. What instrument measures oxygen content in gas samples?

  • A. Explosimeter
  • B. Hygrometer
  • C. Barometer
  • D. Paramagnetic or Electrochemical Oxygen Analyzer
Answer: D — Paramagnetic or Electrochemical Oxygen Analyzer
Paramagnetic oxygen analyzers accurately measure O2 concentrations in gas mixtures.

3. What is the purpose of deck water spray curtains during gas leaks?

  • A. Knock down gas clouds, cool structural steel, and shield radiant heat
  • B. Fill drinking tanks
  • C. Clean anchor chain
  • D. Wash windows
Answer: A — Knock down gas clouds, cool structural steel, and shield radiant heat
Water sprays absorb heat, disperse vapors, and protect hull steel from cold brittle fracture.

4. Who oversees gas cargo watchkeeping and manifold transfers on board?

  • A. Deck Cadet
  • B. Steward
  • C. Chief Cook
  • D. Chief Officer / Designated Cargo Officer
Answer: D — Chief Officer / Designated Cargo Officer
The Chief Officer manages all gas cargo operations and safety enforcement.

5. How frequently must operational drills and practical checks for regulatory compliance and STCW code requirements be conducted for Advanced Liquefied Gas Operations?

  • A. Annually prior to vessel drydocking
  • B. At least monthly or as mandated by SOLAS and shipboard safety management system (SMS)
  • C. Only when requested by port State control inspectors
  • D. Once every 5 years during special survey
Answer: B — 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 Advanced Liquefied Gas Operations?

  • A. Verbal update to port agent without logging
  • B. No written record is required
  • C. Entry in the official Deck or Engine Logbook recording date, time, and operational parameters
  • D. Unsigned note on the shipboard notice board
Answer: C — 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 primary component of LPG Commercial Propane?

  • A. Hydrogen
  • B. Propane (C3H8)
  • C. Oxygen
  • D. Methane (CH4)
Answer: B — Propane (C3H8)
Commercial LPG propane consists mainly of propane gas.

8. At atmospheric pressure, what is the boiling point of propane?

  • A. +100°C
  • B. 42°C
  • C. 162°C
  • D. 0°C
Answer: B — 42°C
Propane boils at -42.1°C under normal atmospheric pressure.

9. What danger is posed by Nitrogen gas leaking into enclosed accommodation spaces?

  • A. Rapid asphyxiation and death without warning due to oxygen deficiency
  • B. Skin itching
  • C. Explosive fire
  • D. High noise
Answer: A — Rapid asphyxiation and death without warning due to oxygen deficiency
Nitrogen displaces air quietly, causing sudden unconsciousness and hypoxia.

10. What type of insulation is used in Technigaz Mark III membrane LNG tanks?

  • A. Fiberglass wool
  • B. Concrete blocks
  • C. Reinforced polyurethane foam (R-PUF) panels with triplex secondary barrier
  • D. Styrofoam cups
Answer: C — Reinforced polyurethane foam (R-PUF) panels with triplex secondary barrier
Mark III uses rigid polyurethane foam insulation panels faced with flexible secondary barriers.

11. What device measures liquid level in LNG tanks without mechanical contact?

  • A. Sight glass
  • B. Sounding tape
  • C. Radar ullage level gauge
  • D. Dipstick
Answer: C — Radar ullage level gauge
Radar gauges transmit microwave signals through tank vapor to measure exact liquid ullage.

12. What requirement applies to electrical equipment installed in gas carrier hazardous zones?

  • A. Household switches allowed
  • B. No certification needed
  • C. Must be certified intrinsically safe (Ex-i) or explosion-proof (Ex-d)
  • D. Bare wires permitted
Answer: C — Must be certified intrinsically safe (Ex-i) or explosion-proof (Ex-d)
Hazardous areas mandate explosion-proof/intrinsically safe electrical apparatus.

13. What is the function of the gas combustion unit (GCU) on an LNG carrier?

  • A. Generate water
  • B. Safely burn excess boil-off gas when engines cannot consume it
  • C. Warm crew cabins
  • D. Cool down tanks
Answer: B — Safely burn excess boil-off gas when engines cannot consume it
GCUs incinerate excess BOG safely to prevent venting methane into atmosphere.

14. What is the upper explosive limit (UEL) of Methane gas in air?

  • A. 2%
  • B. 100%
  • C. 50%
  • D. Approximately 15% by volume
Answer: D — Approximately 15% by volume
Methane flammable range in air is 5% (LEL) to 15% (UEL) by volume.

15. What action is taken if a gas detector alarm activates in the compressor room?

  • A. Evacuate room, trip compressor ESD, and investigate cause upwind with SCBA
  • B. Open window and smoke
  • C. Turn off bell
  • D. Ignore alarm
Answer: A — Evacuate room, trip compressor ESD, and investigate cause upwind with SCBA
Gas alarms signal dangerous hydrocarbon leaks requiring immediate ESD isolation.

16. What publication provides emergency medical guidance for chemical/gas casualties?

  • A. COLREG 1972
  • B. Medical First Aid Guide (MFAG)
  • C. Port Tariff Manual
  • D. Engine Telegraph Guide
Answer: B — Medical First Aid Guide (MFAG)
MFAG details emergency treatments and antidote administration for toxic gas exposures.

17. What type of personal protective equipment (PPE) is essential when handling regulatory compliance and STCW code requirements under Advanced Liquefied Gas Operations guidelines?

  • A. Certified task-specific PPE meeting SOLAS/IMO performance standards
  • B. Standard street clothing with rubber gloves
  • C. High-visibility vest only
  • D. Basic cotton coveralls without eye or foot protection
Answer: A — 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 Advanced Liquefied Gas Operations?

  • A. Temperature check only
  • B. Oxygen level at 15% with ventilation turned off
  • C. Visual inspection through access hatch without gas testing
  • D. Atmospheric oxygen level at 20.9% and zero toxic/flammable gas concentration
Answer: D — 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 density of Methane gas at ambient temperature compared to air?

  • A. Same as water
  • B. Heavier than lead
  • C. Heavier than air
  • D. Lighter than air (relative density ~0.55)
Answer: D — Lighter than air (relative density ~0.55)
Warm methane gas is lighter than air (~0.55 SG) and disperses upward.

20. What is the density of Propane vapor at ambient temperature compared to air?

  • A. Lighter than air
  • B. Same as helium
  • C. Heavier than air (relative density ~1.5)
  • D. Zero weight
Answer: C — Heavier than air (relative density ~1.5)
Propane vapor is 1.5 times heavier than air, collecting in low deck areas and bilges.

21. Why is water prohibited for extinguishing liquid gas jet fires at manifold valves unless flow is stopped first?

  • A. Water ruins paint
  • B. Water freezes gas
  • C. Water turns gas to oil
  • D. Extinguishing flame without stopping gas flow creates unignited gas cloud explosion hazard
Answer: D — Extinguishing flame without stopping gas flow creates unignited gas cloud explosion hazard
Extinguishing gas flames while gas keeps escaping creates huge explosive vapor clouds.

22. What equipment measures dew point (moisture) in Nitrogen or inert gas?

  • A. Manometer
  • B. Pyrometer
  • C. Hydrometer
  • D. Dew point meter / Hygrometer
Answer: D — Dew point meter / Hygrometer
Hygrometers verify dry inert gas (-40°C to -60°C dew point) to prevent ice hydrates.

23. What is the function of a thermal relief valve fitted on liquid gas lines?

  • A. Pump bilges
  • B. Relieve small liquid expansion pressure when trapped between closed line valves
  • C. Cool main engine
  • D. Measure depth
Answer: B — Relieve small liquid expansion pressure when trapped between closed line valves
Thermal relief valves vent tiny liquid quantities to prevent explosive line pressure.

24. What safety system automatically closes manifold valves if ship moves beyond safe berthing limits?

  • A. Rudder indicator
  • B. Anchor drop switch
  • C. Emergency Shutdown (ESD) / Emergency Release System (ERS)
  • D. Auto-pilot
Answer: C — Emergency Shutdown (ESD) / Emergency Release System (ERS)
ERS links monitor vessel movement and trip ESD before loading arm physical limits are exceeded.

25. What gas is produced by incomplete combustion in inert gas generators?

  • A. Argon
  • B. Carbon Monoxide (CO)
  • C. Pure Oxygen
  • D. Helium
Answer: B — Carbon Monoxide (CO)
Incomplete combustion releases toxic Carbon Monoxide (CO) gas.

26. What is the purpose of hold space inerting on LPG tankers?

  • A. Store fresh water
  • B. Prevent flammable atmosphere in void space surrounding cargo tanks
  • C. Wash hold steel
  • D. Keep hold warm
Answer: B — Prevent flammable atmosphere in void space surrounding cargo tanks
Inerting hold spaces eliminates oxygen, preventing fires if cargo leaks from primary tank.

27. What signal alerts crew to immediately evacuate an enclosed space?

  • A. Evacuation alarm sounder / radio order from standby person
  • B. Whistle signal
  • C. Dinner bell
  • D. One short horn blast
Answer: A — Evacuation alarm sounder / radio order from standby person
Standby watchkeepers order immediate evacuation if gas levels rise or ventilation fails.

28. Who is responsible for ensuring all gas tanker crew receive proper safety familiarization?

  • A. Customs Officer
  • B. The Ship's Master and Chief Officer
  • C. Shore crane driver
  • D. Port Agent
Answer: B — The Ship's Master and Chief Officer
Master and safety officers enforce mandatory STCW familiarization before crew start duties.

29. What key responsibility belongs to seafarers performing watchkeeping duties for regulatory compliance and STCW code requirements under Advanced Liquefied Gas Operations?

  • A. Continuous monitoring of operational parameters and immediate reporting of anomalies
  • B. Operating equipment beyond design pressure limits
  • C. Bypassing safety trips during routine operations
  • D. Leaving watchkeeping station unattended
Answer: A — 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 Advanced Liquefied Gas Operations?

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

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