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CDL Test: Tank vehicles questions and answers

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Tank vehicles

35 questions

  1. #1

    You need a tank endorsement if you haul multiple tanks each rated more than 119 gallons and the combined volume is at least:

    1. 500 gallons
    2. 1,000 gallons
    3. 750 gallons
    4. 2,000 gallons

    Answer: B. Each tank over 119 gallons and a combined volume of 1,000 gallons or more requires the endorsement.

    Source: North Dakota CDL Manual (AAMVA model), Section 8, p. 101In summary, if you are hauling multiple tanks each rated more than 119 gallons AND the combined volume of those tanks is 1,000 gallons or more, you need a tank endorsement.

  2. #2

    If you haul only one tank, you need a tank endorsement when that tank's capacity is:

    1. 119 gallons or more
    2. 500 gallons or more
    3. 5,000 gallons or more
    4. 1,000 gallons or more

    Answer: D. A single tank of 1,000 gallons or more requires the endorsement.

    Source: North Dakota CDL Manual (AAMVA model), Section 8, p. 101If you are only hauling one tank and that one tank is 1,000 gallon capacity or more, you need a tank endorsement.

  3. #3

    A CMV carries an empty storage container tank, not designed for transportation, rated 1,000 gallons or more, temporarily attached to a flatbed trailer. It is:

    1. Not considered a tank vehicle
    2. Considered a tank vehicle
    3. Considered a tank vehicle only if the tank is later filled
    4. Considered a tank vehicle only on public roads

    Answer: A. Such an empty storage tank on a flatbed does not make the vehicle a tank vehicle.

    Source: North Dakota CDL Manual (AAMVA model), Section 8, p. 101A commercial motor vehicle transporting an empty storage container tank, not designed for transportation, with a rated capacity of 1,000 gallons or more that is temporarily attached to a flatbed trailer is not considered a tank vehicle.

  4. #4

    A tank endorsement is required for certain vehicles that transport liquids or gases. The liquid or gas:

    1. Must be classified as a hazardous material
    2. Must be flammable, corrosive, or toxic
    3. Does not have to be a hazardous material
    4. Must be carried under pressure in the tank

    Answer: C. Even harmless liquids such as milk can require the tank endorsement.

    Source: North Dakota CDL Manual (AAMVA model), Section 8, p. 101The liquid or gas does not have to be a hazardous material.

  5. #5

    What is the rule about carrying liquids or gases in a leaking tank?

    1. It is allowed if the leak is small
    2. It is allowed if you drive slowly
    3. Never do it; it is a crime
    4. It is allowed on short trips only

    Answer: C. You will be cited, prevented from driving further, and may be liable for cleanup of any spill.

    Source: North Dakota CDL Manual (AAMVA model), Section 8, p. 101Don’t carry liquids or gases in a leaking tank. To do so is a crime.

  6. #6

    When inspecting a tank vehicle's manhole covers and vents, you should make sure that:

    1. The covers have gaskets and close correctly, and the vents are clear
    2. The covers are painted with the cargo name and the vents are capped
    3. The covers are left open a crack and the vents are sealed shut
    4. The covers are welded shut and the vents are plugged to stop leaks

    Answer: A. Clear vents work correctly, and gaskets with proper closing keep the cargo sealed.

    Source: North Dakota CDL Manual (AAMVA model), Section 8, p. 101Check manhole covers and vents. Make sure the covers have gaskets and they close correctly. Keep the vents clear so they work correctly.

  7. #7

    If your tank vehicle has special equipment such as vapor recovery kits, grounding and bonding cables, or emergency shut-off systems, you should:

    1. Remove it before the trip
    2. Use it only when loading
    3. Ignore it if the tank is baffled
    4. Make sure it works

    Answer: D. The manual says to make sure special purpose equipment works.

    Source: North Dakota CDL Manual (AAMVA model), Section 8, p. 101If your vehicle has any of the following equipment, make sure it works:

  8. #8

    Hauling liquids in tanks requires special skills because of:

    1. The tank's paint color and its mounting style
    2. The high center of gravity and liquid movement
    3. The empty weight of the trailer and its axles
    4. The low center of gravity and slow liquid flow

    Answer: B. Both a high center of gravity and moving liquid affect handling.

    Source: North Dakota CDL Manual (AAMVA model), Section 8, p. 101Hauling liquids in tanks requires special skills because of the high center of gravity and liquid movement.

  9. #9

    What does a high center of gravity mean?

    1. The load is carried low and spread evenly
    2. Much of the load's weight is carried high up off the road
    3. The cab sits higher than the trailer
    4. The tank is divided by bulkheads

    Answer: B. A high center of gravity makes the vehicle top-heavy and easy to roll over.

    Source: North Dakota CDL Manual (AAMVA model), Section 8, p. 101High center of gravity means that much of the load’s weight is carried high up off the road.

  10. #10

    Some tanks are divided into smaller tanks by bulkheads. When loading and unloading them, the driver must pay attention to:

    1. Outage only
    2. Surge in each compartment
    3. The color of the liquid
    4. Weight distribution

    Answer: D. Do not put too much weight on the front or rear of the vehicle.

    Source: North Dakota CDL Manual (AAMVA model), Section 8, p. 102When loading and unloading the smaller tanks, the driver must pay attention to weight distribution.

  11. #11

    What is a baffled liquid tank?

    1. A tank with bulkheads that have holes that let the liquid flow through
    2. A tank with no interior bulkheads, so the liquid moves freely end to end
    3. A tank divided into sealed compartments with no openings between them
    4. A tank with a double shell and a layer of insulation between the walls

    Answer: A. The baffles help control forward and backward surge.

    Source: North Dakota CDL Manual (AAMVA model), Section 8, p. 102Baffled liquid tanks have bulkheads in them with holes that let the liquid flow through.

  12. #12

    Un-baffled (smooth bore) tankers have nothing inside to slow down the flow of the liquid. As a result, forward-and-back surge is:

    1. Eliminated
    2. Weaker than in baffled tanks
    3. Very strong
    4. Only a problem when full

    Answer: C. Be extremely cautious, especially when starting and stopping.

    Source: North Dakota CDL Manual (AAMVA model), Section 8, p. 102Therefore, forward-and-back surge is very strong.

  13. #13

    Different liquids require different amounts of outage because:

    1. All liquids freeze at different temperatures
    2. Some liquids are heavier than the tank
    3. Different liquids expand by different amounts
    4. Tanks come in different colors

    Answer: C. You must know the outage requirement when hauling liquids in bulk.

    Source: North Dakota CDL Manual (AAMVA model), Section 8, p. 102Since different liquids expand by different amounts, they require different amounts of outage.

  14. #14

    Because of the high center of gravity and the surge of the liquid, a tank vehicle driver must start, slow down, and stop:

    1. Very smoothly
    2. As quickly as possible
    3. Only with the engine brake
    4. Only on level ground

    Answer: A. Also make smooth turns and lane changes.

    Source: North Dakota CDL Manual (AAMVA model), Section 8, p. 102Because of the high center of gravity and the surge of the liquid, you must start, slow down, and stop very smoothly.

  15. #15

    To control surge when coming to a stop in a tank vehicle, you should:

    1. Pump the brakes repeatedly until the vehicle comes to a stop
    2. Release the brakes just before the vehicle comes to a full stop
    3. Use only the parking brake and let the vehicle roll to a stop
    4. Keep a steady pressure on the brakes and not release too soon

    Answer: D. Releasing too soon lets the liquid surge push the truck.

    Source: North Dakota CDL Manual (AAMVA model), Section 8, p. 102Keep a steady pressure on the brakes. Do not release too soon when coming to a stop.

  16. #16

    In a tank vehicle, you should brake far in advance of a stop and:

    1. Decrease your following distance
    2. Increase your following distance
    3. Use only the engine brake
    4. Shift into neutral

    Answer: B. This gives extra room for the slower, careful stop a tanker needs.

    Source: North Dakota CDL Manual (AAMVA model), Section 8, p. 102Brake far in advance of a stop and increase your following distance.

  17. #17

    If you must make a quick stop in a tank vehicle, remember that steering quickly while braking may cause:

    1. The liquid to freeze
    2. Your vehicle to roll over
    3. The baffles to break loose
    4. The brakes to lock permanently

    Answer: B. Use controlled or stab braking to stop in a quick stop.

    Source: North Dakota CDL Manual (AAMVA model), Section 8, p. 102Also, remember that if you steer quickly while braking, your vehicle may roll over.

  18. #18

    Wet roads double the normal stopping distance. How does this affect a tank vehicle?

    1. You need half as much room to stop
    2. Stopping distance is unchanged
    3. Only empty tankers are affected
    4. You need roughly twice as much room to stop

    Answer: D. Keep in mind how much space you need to stop your vehicle.

    Source: North Dakota CDL Manual (AAMVA model), Section 8, p. 102Remember that wet roads double the normal stopping distance.

  19. #19

    On tank trailers, if your drive wheels or trailer wheels begin to skid, your vehicle may:

    1. Jackknife
    2. Lose its baffles
    3. Run out of outage
    4. Switch to spring brakes

    Answer: A. When any vehicle starts to skid, you must restore traction to the wheels.

    Source: North Dakota CDL Manual (AAMVA model), Section 8, p. 102On tank trailers, if your drive wheels or trailer wheels begin to skid, your vehicle may jackknife.

  20. #20

    To avoid skids in a tank vehicle, you should not:

    1. Check your mirrors for traffic behind you
    2. Keep a steady, moderate speed on slippery roads
    3. Over steer, over accelerate, or over brake
    4. Increase your following distance in bad weather

    Answer: C. These actions may make the vehicle skid.

    Source: North Dakota CDL Manual (AAMVA model), Section 8, p. 102Don’t over steer, over accelerate, or over brake.

  21. #21

    When should a tanker be inspected?

    1. Only after unloading
    2. Only before the first trip of the year
    3. Before loading, unloading, or driving it
    4. Only when carrying hazardous materials

    Answer: C. This makes sure the vehicle is safe to carry the liquid or gas and safe to drive.

    Source: North Dakota CDL Manual (AAMVA model), Section 8, p. 101Before loading, unloading, or driving a tanker, inspect the vehicle.

  22. #22

    When checking the intake, discharge, and cut-off valves on a tank vehicle, you must make sure they are:

    1. In the correct position before loading, unloading, or moving the vehicle
    2. Fully open at all times, including while the vehicle is moving
    3. Locked closed after unloading, and checked only at the end of the trip
    4. Painted in the cargo color code and marked with the last inspection date

    Answer: A. Valve position is part of the inspection of the tank.

    Source: North Dakota CDL Manual (AAMVA model), Section 8, p. 101Make sure the valves are in the correct position before loading, unloading, or moving the vehicle.

  23. #23

    Regarding the emergency equipment required for your tank vehicle, you should:

    1. Carry only the equipment that the shipper happens to provide at the loading dock
    2. Carry it only on long trips and leave it at the terminal on short runs
    3. Rely on other drivers' equipment and on what emergency crews bring
    4. Find out what you are required to carry and make sure you have it and it works

    Answer: D. Check the emergency equipment required for your vehicle.

    Source: North Dakota CDL Manual (AAMVA model), Section 8, p. 101Find out what equipment you’re required to carry and make sure you have it (and it works).

  24. #24

    Tank vehicles come in many types and sizes. To know how to inspect your tank vehicle, you need to check:

    1. The shipper's invoice
    2. The vehicle's operator manual
    3. The state speed limit chart
    4. The tire sidewall markings

    Answer: B. Operator manuals describe the inspection of your specific tank vehicle.

    Source: North Dakota CDL Manual (AAMVA model), Section 8, p. 101You need to check the vehicle’s operator manual to make sure you know how to inspect your tank vehicle.

  25. #25

    On any tank vehicle, the most important item to check during inspection is:

    1. Tire tread
    2. Mirrors
    3. The fire extinguisher
    4. Leaks

    Answer: D. Leaks are the most important item; carrying liquids or gases in a leaking tank is a crime.

    Source: Pennsylvania CDL Manual (PUB 223), 8.1.1 Leakson all tank vehicles, the most important item to check for is leaks.

  26. #26

    Liquid surge in a partly filled tank can:

    1. Shove a stopped truck forward, e.g. into an intersection on ice
    2. Only happen in full tanks
    3. Make the truck stop shorter
    4. Be stopped by braking harder

    Answer: A. When the wave hits the end of the tank it pushes the truck; on ice it can shove a stopped truck into an intersection.

    Source: Pennsylvania CDL Manual (PUB 223), 8.2.2 Danger of SurgeIf the truck is on a slippery surface such as ice, the wave can shove a stopped truck out into an intersection.

  27. #27

    Baffles in a liquid tank reduce front-to-back surge, but:

    1. They eliminate all surge
    2. They make the tank lighter
    3. Side-to-side surge can still occur and cause a rollover
    4. They are required in all sanitary tanks

    Answer: C. Baffles reduce front-to-back surge, but side-to-side surge can still occur and cause a rollover.

    Source: Pennsylvania CDL Manual (PUB 223), 8.2.4 Baffled TanksSide-to-side surge can still occur.

  28. #28

    Why do tanks that haul milk and other food products often have no baffles (smooth bore)?

    1. They carry only full loads
    2. Sanitation rules forbid baffles because they are hard to clean
    3. Baffles would make the tank too heavy
    4. Food liquids do not surge

    Answer: B. Sanitation regulations forbid baffles because of the difficulty of cleaning; forward-and-back surge is very strong.

    Source: Pennsylvania CDL Manual (PUB 223), 8.2.5 Un-baffled Tanks(Sanitation regulations forbid the use of baffles because of the difficulty in cleaning the inside of the tank.)

  29. #29

    Why must you never load a cargo tank totally full?

    1. Full tanks surge more
    2. It is illegal to haul more than half a tank
    3. The vents would freeze
    4. Liquids expand as they warm; you must leave outage

    Answer: D. Liquids expand as they warm, so leave room (outage); different liquids need different amounts.

    Source: Pennsylvania CDL Manual (PUB 223), 8.2.6 OutageLiquids expand as they warm and you must leave room for the expanding liquid.

  30. #30

    Why might you only partly fill a tank with a dense liquid such as some acids?

    1. A full tank could exceed legal weight limits
    2. Dense liquids do not expand
    3. Partial loads never surge
    4. To make inspection easier

    Answer: A. A full tank of dense liquid may exceed legal weight limits, so it is often only partly filled.

    Source: Pennsylvania CDL Manual (PUB 223), 8.2.7 How Much to Load?A full tank of dense liquid (such as some acids) may exceed legal weight limits.

  31. #31

    When stopping a tank vehicle, you should:

    1. Pump the brakes quickly
    2. Release the brakes early to let the liquid settle
    3. Keep steady pressure and not release the brakes too soon
    4. Brake hard at the last moment

    Answer: C. Keep steady brake pressure, do not release too soon, brake far in advance and increase following distance.

    Source: Pennsylvania CDL Manual (PUB 223), 8.3.2 Controlling SurgeKeep a steady pressure on the brakes. do not release the brakes too soon when coming to a stop.

  32. #32

    How should you drive a tank vehicle through a curve?

    1. Brake in the middle of the curve
    2. Slow down before the curve, then accelerate slightly through it
    3. Keep the posted speed
    4. Coast in neutral

    Answer: B. Slow down before curves, then accelerate slightly through; the posted curve speed may be too fast for a tanker.

    Source: Pennsylvania CDL Manual (PUB 223), 8.3.3 CurvesSlow down before curves, then accelerate slightly through the curve.

  33. #33

    Which statement about tank vehicle stopping distance is true?

    1. Wet roads do not change it
    2. Full tanks always take longer to stop
    3. Wet roads cut it in half
    4. Empty tank vehicles may take longer to stop than full ones

    Answer: D. Wet roads double the normal stopping distance, and empty tankers may take longer to stop than full ones.

    Source: Pennsylvania CDL Manual (PUB 223), 8.3.4 Stopping Distanceremember that wet roads double the normal stopping distance. Empty tank vehicles may take longer to stop than full ones.

  34. #34

    Before driving a tank vehicle, the valves and manhole covers must be:

    1. Closed
    2. Open to vent vapors
    3. Removed
    4. Half open

    Answer: A. Never drive a tank vehicle with open valves or manhole covers; covers must have gaskets and close correctly.

    Source: Pennsylvania CDL Manual (PUB 223), 8.1.1 Leaksnever drive a tank vehicle with open valves or manhole covers.

  35. #35

    Tests have shown that tankers can turn over:

    1. Only above 65 mph
    2. Only when empty
    3. At the speed limits posted for curves
    4. Only on gravel

    Answer: C. Tankers can turn over at posted curve speeds; take curves and ramps well below the posted speeds.

    Source: Pennsylvania CDL Manual (PUB 223), 8.2.1 High Center of Gravitytests have shown that tankers can turn over at the speed limits posted for curves.
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