Master < 500-1600 GRT Rivers, Revision & Practice Exams

The atmosphere in a tank is too rich when it is __________.

1. capable of supporting combustion
2. in a noncombustible state which can be relied on to occur naturally on a regular basis
3. incapable of supporting combustion because the hydrocarbon vapor content makes the atmosphere below the LFL (Lower Flammable Level)
4. incapable of supporting combustion because the hydrocarbon vapor content makes the atmosphere above the UFL (Upper Flammable Limit) ✓

What is the purpose of the "reference hand" on an aneroid barometer?

1. To adjust the barometer
2. To indicate any change in the reading of the barometer ✓
3. To provide a correction for height above sea level
4. To provide a correction for temperature changes

What daymark has NO lateral significance?

1. Green square
2. Red triangle with a green horizontal stripe
3. Green and white diamond ✓
4. Red triangle

Who must approve the vessel's trim and stability booklet?

1. Society of Naval Architects and Marine Engineers
2. National Cargo Bureau
3. International Maritime Organization
4. United States Coast Guard ✓

Why: For U.S. inspected vessels the trim and stability booklet must be approved by the Coast Guard, which reviews the stability data and inclining experiment results during plan approval.

Which is the proper way to correct a mistake in the logbook?

1. Draw several lines through the entry, rewrite, and initial the correction
2. Erase the entry and rewrite
3. Completely black out the entry, rewrite, and initial the correction
4. Draw a line through the entry, rewrite, and initial the correction ✓

Which is a disadvantage of using chain lashing on heavy vehicles aboard Ro-Ro vessels?

1. The chain does not absorb shock ✓
2. It can wrap around cargo
3. The chain is affected by temperature
4. It is easily damaged

Great Lakes vessels, using liferafts, must have sufficient liferaft capacity on each side of the vessel to accommodate how many persons onboard?

1. 50% of the persons on board
2. 100% of the persons on board ✓
3. 150% of the crew
4. 100% of the persons normally assigned to those spaces

You are at sea and have received a General Emergency message announcing the outbreak of war in Europe. You are directed to comply with the instructions in NGA (NIMA) PUB 117, Chapter Eight. Which statement is TRUE?

1. You should only enter a port in the danger zone during hours of darkness
2. You should attempt to coordinate with the Shipping Control Team ✓
3. When over 200 miles from a port in the danger zone, you should not darken ship
4. If on a coastwise voyage along the east coast of the U.S., you should put into the nearest port

Safe water buoys may show ONLY which type of light?

1. flashing green lights
2. yellow lights
3. white lights ✓
4. flashing red lights

On a working copy of a weather map what color is the line that represents a stationary front?

1. Alternating red and blue ✓
2. Blue
3. Purple
4. Red

Under the IALA Buoyage Systems, which is TRUE of safe water marks?

1. They must show a composite group-flashing, Fl(2 + 1), green light
2. They may show a quick-flashing, Q(9)15s, white light
3. They may show a white Morse (A) light ✓
4. They may show a composite group-flashing, Fl(2 + 1), red light

Why: IALA safe water marks show white lights with isophase, occulting, single long-flash, or Morse 'A' rhythm. Composite group flashing (2+1) red or green belongs to preferred-channel marks, and Q(9) is a west cardinal characteristic.

How is an occluded front represented on a weather map?

1. A dashed blue line
2. An alternate red and blue line
3. A blue line
4. A purple line ✓

The Light List indicates that a light has a nominal range of 18 miles and is 38 feet high. If the visibility is 6 miles and your height of eye is 15 feet, at which distance will you sight the light?

1. 14.8nm
2. 11.7nm ✓
3. 6.0nm
4. 18.0nm

Which condition(s) is(are) necessary for the formation of dew?

1. A surface warmer than the dew point of the air
2. Available nuclei in the air
3. Moderate winds
4. Clear skies ✓

Why: Dew forms on clear, calm nights when surfaces radiate heat away and cool below the air's dew point; clouds blanket that radiational cooling. A surface warmer than the dew point would prevent condensation, and wind mixes the air.

Which term is given to a light that has a light period shorter than its dark period?

1. Flashing ✓
2. Alternating
3. Pulsating
4. Occulting

The dew point is reached when which condition occurs?

1. The temperature of the air equals the temperature of the seawater
2. The air becomes saturated with water vapor ✓
3. The relative humidity reaches 50%
4. The atmospheric pressure is 14.7 lbs. per square inch

The terminology "able to understand any order spoken by the officers" refers to all of the following situations EXCEPT __________.

1. in response to a fire
2. for deck department crew members to understand the terminology used in the engine room ✓
3. when in response to a man overboard
4. when directing the use of lifesaving equipment

The scuppers had been plugged as required at the time a small oil spill occurs on deck from a leaking dresser coupler. After shutting down the transfer, the engine room should first be informed and then which action should be taken?

1. Rig a fire hose to wash down the deck
2. Spread an absorbent material, such as sawdust ✓
3. Remove the plugs from the scuppers
4. Sound the general alarm

If a cargo of kerosene were considered "too lean" to explode, then it must be __________.

1. above the "explosive range"
2. below the "explosive range" ✓
3. within the "explosive range"
4. None of the above

When should you first have any food or water after boarding a lifeboat or liferaft?

1. After 12 hours
2. After 24 hours ✓
3. Within 48 hours
4. Some food and water should be consumed immediately and then not until 48 hours later.

Which defines the "flammable limits" of an atmosphere?

1. The two temperatures between which an atmosphere will self-ignite
2. The two temperatures between which an atmosphere will burn if an ignition source is present
3. The upper and lower percentage of vapor concentrations in an atmosphere which will burn if an ignition source is present ✓
4. The upper and lower pressures between which an atmosphere will not burn

If you see an individual fall overboard, which action(s) should you take?

1. Throw him/her a life buoy
2. Pass the word to the bridge
3. Hail "man overboard"
4. All of the above ✓

Normally, your vessel is on a voyage of three months duration. How many sanitary inspections are required to be conducted during the voyage?

1. one ✓
2. three
3. six
4. twelve

For insurance purposes, which is a requirement for a general average act?

1. It must be a successful venture ✓
2. There are no losses
3. There must be no imminent peril
4. All of the above

Which agency must approve the safety equipment on board inspected vessels?

1. The U.S. Coast Guard ✓
2. The Occupational Safety and Health Administration (OSHA)
3. The Safety Standards Bureau
4. The National Safety Council

Why: On inspected vessels, lifesaving and other safety equipment must be of types approved by the U.S. Coast Guard, the agency that inspects and certificates the vessel. OSHA and private safety organizations have no such approval authority.

Where a propeller shaft passes through the hull, which device prevents water from entering the hull?

1. Propeller boss
2. Stop-water
3. Stuffing box ✓
4. Sea cock

Why: The stuffing box surrounds the shaft where it penetrates the hull; packing compressed by a gland seals against sea water while still letting the shaft rotate. A sea cock is a hull valve, not a shaft seal.

What power source actuates a solenoid valve?

1. Mechanical force
2. Electric current ✓
3. Hydraulic pressure
4. Air pressure

Why: A solenoid is a coil of wire; electric current through the coil creates a magnetic field that moves a plunger to open or close the valve. No hydraulic, pneumatic, or mechanical input operates it.