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BIGF exit exam questions and answers — Set 3

Set 3 of the Basic Training for Ships subject to the IGF Code (BIGF) exit exam bank — 30 of 181 questions, with the correct option marked, and 20 of them also carry a one-line explanation. 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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30 of 30 shown · Set 3

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Set 3 — 30 BIGF exit exam questions with answers

1. Cargo area contains

  • A. cargo containment system
  • B. cargo pumps
  • C. All of the above
  • D. compressor rooms
Answer: C — All of the above

2. Cargo containment system is the arrangement for containment of cargo including where fitted with

  • A. primary barriers
  • B. associated insulations
  • C. secondary barriers
  • D. All of the above
Answer: D — All of the above
Propane boils at -42.1°C at atmospheric pressure; its vapor is approximately 1.5 times heavier than air, causing leaks to settle in low areas.

3. ______________ is the process in which vapour boil- off from acrgo tanks is condensed in a cargo condenser in which the coolant is a refrigerant gas such as R 22.

  • A. Boil-off
  • B. Cascade Reliquefaction Cycle
  • C. BLEVE
  • D. Boiling Point
Answer: B — Cascade Reliquefaction Cycle

4. _____________ is the process occurring within the impeller of a pump when pressure at the inlet to the impeller falls below the vapour pressure of the liquid being pumped.

  • A. Cascade Reliquefaction Cycle
  • B. Boil-off
  • C. Cavitation
  • D. BLEVE
Answer: C — Cavitation
Ethylene boils at -103.7°C at atmospheric pressure and is transported in specialized semi-pressurized or fully refrigerated ethylene carriers.

5. In Cavitation process, the bubbles of vapour that are formed collapse with impulsive force in the _________ pressure regions of the impeller.

  • A. medium
  • B. lower
  • C. higher
  • D. zero
Answer: C — higher
Propylene (propene) has a boiling point of -47.6°C at atmospheric pressure and is carried under refrigeration or pressure in LPG carriers.

6. Cavitation effect can cause significant damage to the

  • A. pumps may lose suction
  • B. impeller surfaces
  • C. both (a) and (b)
  • D. none of the above
Answer: C — both (a) and (b)
Anhydrous ammonia boils at -33.3°C; it is toxic, corrosive to copper and copper alloys, and has an alkaline, pungent odor.

7. What are checked during the certificate of Fittness?

  • A. structure
  • B. All of the above
  • C. equipment
  • D. fittings
Answer: B — All of the above

8. ___________ ia the isolating space on a ship between two adjacent steel bulkheads or deck

  • A. Cofferdam
  • B. Cargo conatinment system
  • C. Compressor pumps
  • D. Cavitation
Answer: A — Cofferdam
Chemical gas carriers carry unsaturated hydrocarbons and monomers that can react or polymerize unless treated with suitable chemical inhibitors.

9. Cofferdam is the isolating space on a ship between __________

  • A. both (a) and (b)
  • B. none of the above
  • C. deck
  • D. two adjacent steel bulkheads
Answer: A — both (a) and (b)

10. ___________ is the reliquefied gases which collect in the condenser and which are then returned to the cargo tanks.

  • A. BLEVE
  • B. Cofferdam
  • C. Condensate
  • D. Aerating
Answer: C — Condensate

11. Compression Ratio is the ratio of the absolute _____________ the discharge from a compressor divided by the absolute pressure at the suction

  • A. mass
  • B. temperature
  • C. pressure
  • D. volume
Answer: C — pressure

12. _____________ is the ratio of the absolute pressure at the discharge from a compressor divided by the absolute pressure at the suction

  • A. Temperature Ratio
  • B. Compression Ratio
  • C. Compressing ratio
  • D. Freezing ratio
Answer: B — Compression Ratio

13. Natural gas contains ________ quantities of heavier hydrocarbons

  • A. zero
  • B. medium
  • C. bigger
  • D. smaller
Answer: D — smaller

14. Natural gas contains smaller quantities of ______hydrocarbons

  • A. medium
  • B. heavier
  • C. lighter
  • D. partial
Answer: B — heavier

15. Natural gas contains smaller quantities of heavier ________

  • A. hydrocarbons
  • B. carbons
  • C. nitrogen
  • D. oxygen
Answer: A — hydrocarbons
Cryogenic liquid fuel leaks cause severe cold contact burns, frostbite, and extreme embrittlement of standard mild structural steel.

16. Natural gas contains smaller quantities of heavier hydrocarbons collectively called as _________

  • A. Neutral Gas Liquid
  • B. Natural Gas Limit
  • C. Natural Gas Liquid
  • D. Nitrogen Gas Liquid
Answer: C — Natural Gas Liquid
Natural Gas Liquids (NGL) refer to the heavier hydrocarbon components (ethane, propane, butane, pentane plus) separated from raw natural gas streams.

17. What are the things Natural gas contains in varying amounts?

  • A. carbondioxide
  • B. hydrocarbon
  • C. All of the above
  • D. water
Answer: C — All of the above
Raw natural gas contains methane, ethane, propane, butane, inert gases (nitrogen, helium), and acid contaminants (CO2, H2S, mercaptans).

18. What are the acid gases removed in liquefaction plant?

  • A. carbon dioxide
  • B. none of the above
  • C. both (a) and (b)
  • D. hydrogen sulphide
Answer: C — both (a) and (b)
Acid gases like carbon dioxide (CO2) and hydrogen sulfide (H2S) must be scrubbed from natural gas before liquefaction to prevent corrosion and freezing.

19. In liquefaction plant which gas is removed as it freezes at a temperature above boiling point of Liquified Natural Gas

  • A. methane
  • B. ethane
  • C. carbon dioxide
  • D. hydrocarbons
Answer: C — carbon dioxide
Carbon dioxide freezes at -78.5°C, well above the liquefaction temperature of LNG (-162°C), and must be removed to prevent solid plugging in heat exchangers.

20. In liquefaction plant which toxic compound is removed?

  • A. All of the above
  • B. nitrogen sulphide
  • C. hydrogen sulphide
  • D. carbondioxide
Answer: C — hydrogen sulphide
Hydrogen sulfide (H2S) is a highly toxic, corrosive gas removed during gas sweetening processes to meet safety and transport specifications.

21. In liquefaction plant, fractionating unit name the gas which is split?

  • A. Butane
  • B. none of the above
  • C. Propane
  • D. both (a) and (b)
Answer: D — both (a) and (b)

22. In liquefaction plant, which gas is liquefied into end product?

  • A. Oxygen
  • B. none of the above
  • C. hydrogen
  • D. Methane
Answer: D — Methane
In an LNG liquefaction plant, the purified, chilled methane stream is liquefied and sent to cryogenic storage tanks as the final LNG product.

23. What is the atmospheric boiling point of methane gas?

  • A. atmospheric boiling point is +172deg C
  • B. atmospheric boiling point is - 162deg C
  • C. atmospheric boiling point is +192deg C
  • D. atmospheric boiling point is +162deg C
Answer: B — atmospheric boiling point is - 162deg C
The boiling point of methane at normal atmospheric pressure (1.013 bar) is approximately -161.5°C (standard rounded to -162°C).

24. The basic liquefaction processes in current use are

  • A. Pre-cooled mixed refrigerant process
  • B. Pure refrigerant cascade process
  • C. All of the above
  • D. Mixed refrigerant process
Answer: C — All of the above
Major commercial LNG liquefaction cycles include the C3MR (propane pre-cooled mixed refrigerant) process, cascade cycles, and nitrogen expansion loops.

25. In Pre-cooled mixed refrigerant process, what is MCR

  • A. Multi Component Refrigerant
  • B. Multi Cascade Refinement
  • C. Minimum Combination Refrigerant
  • D. Multi Cascade Refrigerant
Answer: A — Multi Component Refrigerant
MCR stands for Multi-Component Refrigerant (or Mixed Refrigerant), utilizing a optimized blend of nitrogen, methane, ethane, and propane.

26. In Pre-cooled mixed refrigerant process, Multi Component Refrigerant is a combination of

  • A. both (a) and (b)
  • B. none of the above
  • C. mixed refrigerant cycles
  • D. pure refrigerant cascadecycles
Answer: A — both (a) and (b)
The mixed refrigerant stream in LNG liquefaction plants consists of tailored mixtures of nitrogen, methane, ethane/ethylene, propane, and butane.

27. Liquefied Petroleum Gas is obtained from the refining of __________

  • A. All of the above
  • B. crude oil
  • C. Vegetable oil
  • D. fatty oil
Answer: B — crude oil
Commercial LPG is produced both by extracting NGLs from natural gas processing and through fractional distillation and catalytic cracking of crude oil.

28. In production of chemical gases, from Propane which gas is produced indirectly

  • A. ammonia
  • B. All of the above
  • C. vinyl chloride
  • D. ethylene
Answer: B — All of the above
Propane dehydrogenation and petrochemical cracking processes produce chemical intermediates such as propylene, ethylene, and downstream derivatives.

29. In production of chemical gases, The ethylene stream can be synthesized with chlorine to manufacture __________

  • A. vinyl chloride
  • B. ethylene
  • C. All of the above
  • D. ammonia
Answer: A — vinyl chloride
Ethylene is chlorinated to form ethylene dichloride (EDC), which is then thermally cracked to produce Vinyl Chloride Monomer (VCM) for PVC production.

30. In production of chemical gases, The methane stream is first reformed with steam into _________

  • A. nitrogen
  • B. hydrogen
  • C. vinyl chloride
  • D. carbondioxide
Answer: B — hydrogen
In chemical synthesis, methane is reacted with high-temperature steam over a nickel catalyst in steam methane reforming (SMR) to produce hydrogen and carbon monoxide.

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