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CHEMCO exit exam questions and answers — Set 7 — Advanced Training for Chemical Tanker Cargo Operations

Set 7 of the Advanced Training for Chemical Tanker Cargo Operations (CHEMCO) exit exam bank — 30 of 663 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.

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Set 7 — 30 CHEMCO exit exam questions with answers

1. When evacuating a seaman by helicopter lift, the vessel should be__________.

  • A. stopped with the wind dead ahead
  • B. stopped with the wind on the beam
  • C. underway with the wind 30° on the bow
  • D. underway on a course to provide no apparent wind
Answer: C — underway with the wind 30° on the bow
IAMSAR guidance is for the ship to be underway at a steady speed with the wind about 30° on the bow, normally the port bow when hoisting from aft, so the helicopter can hover into the wind with good visibility and minimal turbulence from the superstructure.

2. A rescue helicopter's hoist area should have a radius of at least __________.

  • A. 6 feet of clear deck
  • B. 10 feet of clear deck
  • C. 25 feet of clear deck
  • D. 50 feet of clear deck
Answer: D — 50 feet of clear deck
IAMSAR guidance and the USCG bank call for a clear hoisting area of at least 50 feet radius, free of masts, rigging and loose objects, so the helicopter's winch and rotor clearance are safe.

3. Usually the most gentle way of riding out a severe storm on a larger vessel is__________.

  • A. head on at slow speeds
  • B. hove to
  • C. running before the seas
  • D. to rig a sea anchor
Answer: C — running before the seas
Running before the seas generally gives the gentlest motion in a severe storm, since the relative speed of the waves is reduced. It has risks of pooping and broaching if speed is not managed carefully.

4. Your vessel is off a lee shore in heavy weather and laboring. Which action should you take?

  • A. Put the sea and wind about two points on either bow and reduce speed.
  • B. Heave to in the trough of the sea.
  • C. Put the sea and wind on either quarter and proceed at increased speed.
  • D. Put the bow directly into the sea and proceed at full speed.
Answer: A — Put the sea and wind about two points on either bow and reduce speed.
Off a lee shore the vessel must keep its head to the weather and avoid being set down. Putting the wind and sea about two points on either bow with reduced speed lessens pounding and labouring while maintaining steerage and holding off the shore.

5. You are steaming in a heavy gale and find it necessary to heave to. Under most circumstances, this is best done by __________.

  • A. stopping the engines and drifting beam to the seas
  • B. going slow astern and taking the seas on the quarter
  • C. taking the sea fine on the bow and reducing the speed to the minimum to hold that position
  • D. maintaining speed and taking the sea broad on the bow
Answer: C — taking the sea fine on the bow and reducing the speed to the minimum to hold that position
Heaving to in a heavy gale is best done by bringing the sea fine on the bow and reducing speed to the minimum that holds that heading. This reduces pounding and keeps the ship from falling into the trough.

6. Snow has obliterated surface features and the sky is covered with uniform, altostratus clouds. There are no shadows and the horizon has disappeared. What is this condition called?

  • A. Ice blink
  • B. Whiteout
  • C. Water sky
  • D. Aurora reflection
Answer: B — Whiteout
A whiteout occurs over snow or ice under a uniform overcast sky, when diffuse light removes all shadows and contrast so that surface features and the horizon disappear, making judgement of distance and depth impossible.

7. A vessel is wind rode when it is __________.

  • A. at anchor and heading into the wind
  • B. backing into the wind
  • C. carrying lee rudder
  • D. necessary to apply a leeway correction to the course
Answer: A — at anchor and heading into the wind
A vessel is wind rode when lying at anchor with its head into the wind, because the wind has a stronger effect on its heading than the current. A tide rode ship lies to the current.

8. When evacuating a seaman by helicopter lift, which course should the ship take?

  • A. Downwind so that the apparent wind is close to nil.
  • B. A course that will keep a free flow of air, clear of smoke, over the hoist area.
  • C. A course that will have the hoist area in the lee of the superstructure.
  • D. With the wind dead ahead because the helicopter is more maneuverable when going into the wind.
Answer: B — A course that will keep a free flow of air, clear of smoke, over the hoist area.
During helicopter hoisting the ship should steer a course that gives a free flow of air over the hoist area, clear of funnel smoke and turbulence, so the pilot has good visibility and stable hover conditions, as advised in IAMSAR Volume III.

9. When the gyro-pilot is used for steering, what control is adjusted to compensate for varying sea conditions?

  • A. Rudder control
  • B. Sea control
  • C. Lost motion adjustment
  • D. Weather adjustment
Answer: D — Weather adjustment
The weather adjustment control on a gyro-pilot sets a dead band so that the autopilot does not respond to small yaws caused by sea conditions. This reduces unnecessary rudder movement and wear in heavy weather.

10. What types of mooring lines are used for larger tankers?

  • A. Ropes with high elastic elongation properties
  • B. Ropes with low plastic elongation properties
  • C. Ropes with high modulus of rigidity
  • D. Strain hardened ropes
Answer: C — Ropes with high modulus of rigidity
OCIMF Mooring Equipment Guidelines require large tankers to use mooring lines with low elongation, such as steel wire or high modulus synthetic fibre ropes, so the ship's movement at the berth is limited and loads are shared evenly between lines.

11. Normally Brakes must be ___________tightened to achieve the required holding capacity of the line's Minimum Breaking Load.

  • A. 30%
  • B. 50%
  • C. 60%
  • D. 75%
Answer: C — 60%
OCIMF Mooring Equipment Guidelines recommend that winch brakes be set to hold 60% of the minimum breaking load of the line, so the brake renders before the line parts and protects the rope and fittings.

12. ‘It is preferred to have all mooring lines of the same material and construction’ This is strictly followed due to

  • A. The load on all the mooring lines should be same
  • B. To avoid undue stress on mooring lines
  • C. To increase the life of the mooring lines
  • D. To avoid compressive over loading of any of the mooring ropes
Answer: B — To avoid undue stress on mooring lines
Lines of different material or construction stretch differently under load, so stiffer lines take a disproportionate share and may be overstressed. Using the same material and construction ensures loads are shared evenly and avoids undue stress on individual lines, as advised by OCIMF.

13. How to prevent failure of the mooring and other components in the mooring system during large swell conditions?

  • A. By attaching fibre tails in the mooring ropes
  • B. By attaching fibre tails on the ends in the mooring ropes
  • C. By attaching fibre tails on the sides of the mooring ropes
  • D. By attaching fibre tails perpendicular to the mooring ropes
Answer: B — By attaching fibre tails on the ends in the mooring ropes
Fitting synthetic fibre tails at the ends of steel wire or HMSF mooring lines adds elasticity, absorbing dynamic loads from swell and ship motion, which prevents failure of the lines and fittings, as recommended in the OCIMF Mooring Equipment Guidelines.

14. Mooring winch brakes should be tested at regular intervals, not exceeding _____. Choose the correct period from below?

  • A. 18 months
  • B. 12 months
  • C. 24 months
  • D. 30months
Answer: B — 12 months
OCIMF Mooring Equipment Guidelines recommend that the holding capacity of mooring winch brakes be tested at regular intervals not exceeding 12 months, and after any event that could affect brake performance.

15. What is the possible alternate for winch-stowed steel wire ropes for the mooring of large tankers at terminals?

  • A. Low Modulus synthetic fibre ropes
  • B. High Modulus synthetic wire ropes
  • C. High Modulus synthetic fibre ropes
  • D. Low Modulus nylon ropes
Answer: C — High Modulus synthetic fibre ropes
High modulus synthetic fibre ropes such as HMPE or aramid have very low elongation similar to steel wire but are far lighter and easier to handle, so they are the accepted alternative to winch-stowed wires on large tankers under OCIMF guidance.

16. Why mooring wires used by large tankers are normally stored on self- stowing mooring winches?

  • A. Self - stowing winches are convenient
  • B. Weight and size make manual handling difficult
  • C. Self – stowing winches have brakes
  • D. Self-stowing winches are reliable
Answer: B — Weight and size make manual handling difficult
Steel wire mooring ropes on large tankers are very heavy and of large diameter, so manual handling would be difficult and dangerous. They are therefore kept on self-stowing winch drums for safe and efficient handling.

17. What is IOPC fund?

  • A. International Oil Pollution Compensation Funds
  • B. International Oil tanker Pollution Compensation Funds
  • C. International Oil and hazardous chemical Compensation Funds
  • D. International Oil Pollution Compensatory Funds
Answer: A — International Oil Pollution Compensation Funds
The IOPC Funds are the International Oil Pollution Compensation Funds, established under the 1971 and 1992 Fund Conventions, which provide compensation for oil pollution damage from tankers beyond the shipowner's liability under the CLC.

18. In March 1989, Exxon Valdez ran aground in Alaska (U.S.) spilling approximately 40,000 tons of crude oil into the sea, causing serious environmental damage. What was the outcome legislation that followed the disaster?

  • A. CLC Convention and the Fund Convention
  • B. Oil Pollution Act of 1990 (OPA 90)
  • C. Bunker Convention
  • D. LLMC Convention
Answer: B — Oil Pollution Act of 1990 (OPA 90)
The Exxon Valdez grounding in Prince William Sound in 1989 led the United States to enact the Oil Pollution Act of 1990, which introduced vessel response plans, double hull requirements and greater liability for tanker owners.

19. What does LLMC Convention stand for?

  • A. Convention on Limitations of Liabilities for Maritime Claims
  • B. Conventionon Limited Liabilities for Marine Claims
  • C. Convention on Liabilities limited for Marine Claims
  • D. Convention on Liabilities with Limits for Maritime Claims
Answer: A — Convention on Limitations of Liabilities for Maritime Claims
LLMC is the Convention on Limitation of Liability for Maritime Claims, 1976, which allows shipowners and salvors to limit their liability for certain claims to amounts based on the ship's tonnage.

20. The meaning of the CLC Convention is,

  • A. Civil Liability Convention for Oil Pollution Damage
  • B. Civil Liability Convention for Damage from NLS
  • C. Civil Liability Convention for Air Pollution
  • D. Civil Liability Convention for pollution by Sewage
Answer: A — Civil Liability Convention for Oil Pollution Damage
CLC is the International Convention on Civil Liability for Oil Pollution Damage, 1969 and its 1992 Protocol, which places strict liability on the tanker owner for oil pollution damage and requires compulsory insurance.

21. Under which operation the volumetric cargo losses are more?

  • A. During Tank to tank transfer onboard
  • B. During Ship to shore transfer
  • C. During COW
  • D. During circulation inside the same Tank onboard
Answer: B — During Ship to shore transfer
Volumetric cargo losses are greatest during ship to shore transfer because of evaporation of light ends, vapour release, line contents, measurement differences and clingage. This is the stage where most transit loss claims arise.

22. In spite of using clean sample bottles to acquire individual samples from each level (ie top, middle and bottom of each of the ship’s tanks) and clearly labelled for density calculation, why the final result may not provide the correct density value?

  • A. Due to temperature variations
  • B. Due to Viscosity variations
  • C. Due to the loss of volatile fractions to atmosphere
  • D. Due to changes in Emulsion
Answer: C — Due to the loss of volatile fractions to atmosphere
Even with clean, labelled bottles, lighter volatile fractions evaporate during sampling, handling and storage, which changes the composition of the sample and makes the measured density unrepresentative of the cargo.

23. What can be the probable causes for a gross mismatch between ship and shore oil figures?

  • A. Ullages incorrectly measured, Tanks filled but not taken into account, The contents of pipelines not allowed for, Cargo mistakenly loaded on top of ballast and Cargo lost in the shore installation.
  • B. Incorrectly measured Ullages/ Temperatures/ densities, Tanks filled but not taken into account, The contents of pipelines not allowed for, Incorrect temperatures or densities, Cargo mistakenly loaded on top of ballast and Cargo lost in the shore installation.
  • C. Ullages incorrectly measured, Tanks filled but not taken into account, The contents of pipelines not allowed for, Incorrect temperatures or densities, and Cargo lost in the shore installation.
  • D. Ullages incorrectly measured, The contents of pipelines not allowed for, Incorrect temperatures or densities, Cargo mistakenly loaded on top of ballast and Cargo lost in the shore installation.
Answer: B — Incorrectly measured Ullages/ Temperatures/ densities, Tanks filled but not taken into account, The contents of pipelines not allowed for, Incorrect temperatures or densities, Cargo mistakenly loaded on top of ballast and Cargo lost in the shore installation.
Gross ship and shore discrepancies usually result from errors in ullage, temperature or density measurement, tanks filled but not accounted for, pipeline contents not allowed for, cargo loaded on top of ballast, and losses within the shore installation. The fullest list covers all these causes.

24. Normally which one will affect the final cargo measurement more when there is a 0.1% variation in their respective reading?

  • A. Ullage measurement
  • B. Density measurement
  • C. Temperature measurement
  • D. Water in cargo measurement
Answer: C — Temperature measurement
Temperature errors have a large effect on cargo calculation because the volume correction factor depends on temperature, so a small error in temperature reading changes the standard volume of the entire cargo. The bank treats temperature as the most sensitive measurement.

25. Why water finding pastes or electronic tape interface reading to measure water in the take do not give accurate results?

  • A. Due to emulsion
  • B. Due to temperature difference
  • C. Due temperature and density difference
  • D. Due to differences in Viscosity
Answer: A — Due to emulsion
Water finding paste and interface probes can give inaccurate results when there is an emulsion layer between oil and free water, because there is no clear interface to detect, so the water cut may be misread.

26. What are all the Claims/ disputes you can successfully defend if some records if maintained on board properly?

  • A. Shortage, contamination and demurrage / dispatch disputes.
  • B. Shortage, performance claims, and demurrage / dispatch disputes.
  • C. Shortage, contamination, performance claims, and demurrage / dispatch disputes.
  • D. Contamination performance claims, and demurrage / dispatch disputes.
Answer: B — Shortage, performance claims, and demurrage / dispatch disputes.
Properly maintained records such as ullage reports, pumping logs, notices of protest and speed and consumption data enable the ship to defend shortage claims, performance claims and demurrage or despatch disputes.

27. What are the factors that may affect the calculation of OBQ value?

  • A. Residues on tank floors, the age of the vessel and previous cargoes carried.
  • B. Residues on tank floors and previous cargoes carried.
  • C. Residues on tank floors and structures, and previous cargoes carried.
  • D. Residues on tank floors and structures, and these will vary with the age of the vessel and previous cargoes carried.
Answer: D — Residues on tank floors and structures, and these will vary with the age of the vessel and previous cargoes carried.
On board quantity depends on residues remaining on tank floors and structures, which vary with the age of the vessel, the condition of its tanks and coatings, and the previous cargoes carried.

28. What are all the cargo measurement issues creep up when liquid cargo is measured for volume calculations

  • A. Ullage, listing of vessel, sea conditions, and temperature of cargo
  • B. Ullage, listing of vessel, sea conditions, water in cargo and temperature of cargo
  • C. Ullage, listing of vessel, sea conditions, water in cargo, density and temperature of cargo
  • D. Ullage, listing of vessel, water in cargo, density and temperature of cargo
Answer: B — Ullage, listing of vessel, sea conditions, water in cargo and temperature of cargo
Volume measurement of liquid cargo is affected by ullage readings, list and trim of the vessel, sea conditions, water in the cargo and cargo temperature. These factors must all be corrected for to obtain accurate gross and net volumes.

29. What can be the ship’s defence if the Oil discharged from board is more than the B/L figure?

  • A. Water seepage into cargo onboard the ship
  • B. The onboard quantity (OBQ) prior to loading has not been taken into consideration
  • C. The cargo has been slightly over heated to reduce viscosity
  • D. The flow meter on the shore at the discharge port is not working well
Answer: B — The onboard quantity (OBQ) prior to loading has not been taken into consideration
If the ship discharges more than the bill of lading figure, the likely explanation is that the on board quantity before loading was not taken into account. Including the OBQ in the vessel experience factor and calculations reconciles the difference.

30. What are all the normal defence for the Ship, in case of an ‘Oil Shortage’

  • A. To prove that all the cargo has been discharged with no (ROB).
  • B. To prove that there was no significant in-transit loss
  • C. To prove that the ship tank calibrations are more accurate than the shore tank calibrations.
  • D. To prove that the shore’s flow meter is wrong
Answer: A — To prove that all the cargo has been discharged with no (ROB).
The ship's primary defence against an oil shortage claim is to prove that all cargo was discharged and no cargo remained on board, supported by dry tank certificates and ROB measurements witnessed by the surveyor.

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