CDL Tanker Endorsement Practice Test

All 35 questions with answers

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1. Which letter marks the tank vehicle endorsement on a CDL?

   1. N
   2. T
   3. X
   4. H
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   A. N N is tank vehicle. T is doubles/triples, H is hazardous materials, and X is the combined tank and hazmat endorsement. (49 CFR 383.153)

2. A tank counts toward the tank endorsement when its own rated capacity is more than:

   1. 119 gallons
   2. 500 gallons
   3. 250 gallons
   4. 55 gallons
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   A. 119 gallons Each tank must be rated at more than 119 gallons, and all the tanks together must add up to 1,000 gallons or more. (49 CFR 383.5)

3. Together, the tanks on a vehicle need an aggregate rated capacity of at least ___ before the endorsement is required.

   1. 1,000 gallons
   2. 2,500 gallons
   3. 500 gallons
   4. 800 gallons
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   A. 1,000 gallons An aggregate rated capacity of 1,000 gallons or more, with each tank over 119 gallons, whether the tanks are permanently or temporarily attached. (49 CFR 383.5)

4. You will haul drinking water in a 5,000-gallon tank on a Class B truck. Do you need the tank endorsement?

   1. Only when crossing state lines
   2. Yes; the liquid does not have to be hazardous
   3. No; water is not a hazardous material
   4. Only if the tank is baffled
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   B. Yes; the liquid does not have to be hazardous The endorsement is about how bulk liquid handles, not about what the liquid is. Water, milk and fuel all count if the tanks meet the size rules. (CDL manual: Tank Vehicles)

5. When does the driver of a Class C vehicle need a tank endorsement?

   1. When hauling hazardous materials in liquid or gas form in tanks of the covered size
   2. Never; it only applies to Class A
   3. Whenever the vehicle carries any liquid
   4. Only when the tank is empty
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   A. When hauling hazardous materials in liquid or gas form in tanks of the covered size For Class A and B the endorsement covers any liquid or gas in the covered tanks. For Class C it applies when the load in those tanks is hazardous material. (CDL manual: Tank Vehicles)

6. A tank driver who also hauls placarded hazardous materials needs which endorsement?

   1. P
   2. T
   3. X
   4. S
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   C. X X is the combination of the tank vehicle (N) and hazardous materials (H) endorsements. (49 CFR 383.153)

7. A learner’s permit (CLP) holder with an N endorsement may drive:

   1. A loaded tanker on private roads only
   2. Only an empty tank vehicle
   3. Any tank vehicle under 3,000 gallons
   4. A loaded tanker if a CDL holder rides along
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   B. Only an empty tank vehicle A CLP with the N endorsement carries the X restriction: no cargo in the tank, and no tank that held hazardous materials unless it has been purged. (CDL manual: Introduction (restrictions))

8. On any tank vehicle, the most important thing to check during inspection is:

   1. Leaks
   2. Tire pressure
   3. The fuel level
   4. The paint on the shell
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   A. Leaks Look under and around the vehicle for any sign of leaking, and check the shell, valves, pipes, hoses and joints. (CDL manual: Tank Vehicles)

9. What happens if you drive a tank that is leaking its cargo?

   1. It is a crime: you can be cited, stopped from driving further and made to pay for the clean-up
   2. Nothing, if the leak is small
   3. You get a warning only
   4. Only the shipper is responsible
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   A. It is a crime: you can be cited, stopped from driving further and made to pay for the clean-up Carrying liquids or gases in a leaking tank is illegal. You may also be liable for cleaning up the spill. (CDL manual: Tank Vehicles)

10. When inspecting manhole covers and vents, you should make sure:

    1. The covers are removed before loading
    2. The covers are open so the tank can breathe
    3. The vents are sealed shut
    4. The covers have gaskets and close correctly, and the vents are clear
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    D. The covers have gaskets and close correctly, and the vents are clear Gaskets must be in place and covers must close properly. Vents must be kept clear so they work. (CDL manual: Tank Vehicles)

11. The intake, discharge and cut-off valves should be:

    1. Left open while driving
    2. Checked once a week
    3. Adjusted only by the shipper
    4. In the correct position before loading, unloading or moving the vehicle
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    D. In the correct position before loading, unloading or moving the vehicle Check the valves and make sure each one is set correctly before you load, unload or move. Never drive with open valves or manhole covers. (CDL manual: Tank Vehicles)

12. Which of these is special-purpose tank equipment you should check if your vehicle has it?

    1. A standee line
    2. A converter dolly
    3. Grounding and bonding cables
    4. A stop signal arm
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    C. Grounding and bonding cables Also vapor recovery kits, emergency shut-off systems and a built-in fire extinguisher. If the equipment is fitted, it must work. (CDL manual: Tank Vehicles)

13. Why are liquid tankers especially easy to roll over?

    1. Much of the weight is carried high off the road
    2. Their brakes are weaker
    3. Their tires are narrower
    4. They have fewer axles
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    A. Much of the weight is carried high off the road A high center of gravity makes the vehicle top-heavy. Liquid movement adds to the problem. (CDL manual: Tank Vehicles)

14. Tests have shown that tankers can turn over:

    1. Only when empty
    2. Only above 65 mph
    3. Only on wet roads
    4. At the speed limits posted for curves
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    D. At the speed limits posted for curves Posted curve speeds are set for cars. Take highway curves and on and off ramps well below the posted speed. (CDL manual: Tank Vehicles)

15. Liquid surge happens when:

    1. A tank is completely full
    2. The engine is idling
    3. The tank is empty
    4. A tank is only partly full and the liquid moves
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    D. A tank is only partly full and the liquid moves The liquid in a partly filled tank moves back and forth, and that movement can badly affect handling. (CDL manual: Tank Vehicles)

16. You come to a stop on an icy road with a partly loaded tank. What can the surge do?

    1. Push the stopped truck forward into an intersection
    2. Nothing once the truck has stopped
    3. Lift the front wheels
    4. Lock the trailer brakes
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    A. Push the stopped truck forward into an intersection When the wave hits the end of the tank it pushes the truck the way the wave is moving. On a slippery surface that can shove a stopped truck forward. (CDL manual: Tank Vehicles)

17. Bulkheads divide a tank into smaller tanks. When loading and unloading them, you must watch:

    1. Weight distribution, so the front or rear is not overloaded
    2. The outside temperature
    3. The color of the liquid
    4. Only the rear compartment
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    A. Weight distribution, so the front or rear is not overloaded Filling or emptying compartments changes where the weight sits. Do not put too much on the front or rear of the vehicle. (CDL manual: Tank Vehicles)

18. What are baffles?

    1. Covers over the manholes
    2. Solid walls that seal off separate compartments
    3. Pumps that move liquid between tanks
    4. Bulkheads with holes that let liquid flow through and slow the front-to-back surge
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    D. Bulkheads with holes that let liquid flow through and slow the front-to-back surge Baffles help control forward and backward surge. Bulkheads without holes split a tank into separate smaller tanks. (CDL manual: Tank Vehicles)

19. In a baffled tank, what kind of surge can still happen?

    1. None; baffles stop all surge
    2. Only upward surge
    3. Only surge when the tank is full
    4. Side-to-side surge, which can cause a rollover
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    D. Side-to-side surge, which can cause a rollover Baffles slow the fore-and-aft movement but not the side-to-side movement, which can tip the vehicle in a turn or lane change. (CDL manual: Tank Vehicles)

20. A "smooth bore" tank is one that:

    1. Has nothing inside to slow the liquid, so front-to-back surge is very strong
    2. Is always divided by bulkheads
    3. Has baffles every few feet
    4. Carries only gases
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    A. Has nothing inside to slow the liquid, so front-to-back surge is very strong With no baffles, the whole load surges forward and back. Be very slow and careful, especially when starting and stopping. (CDL manual: Tank Vehicles)

21. Why do tanks for food products such as milk usually have no baffles?

    1. Sanitation rules forbid them because baffled tanks are hard to clean
    2. Baffles make the tank too heavy
    3. Milk does not surge
    4. Food tankers are always full
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    A. Sanitation rules forbid them because baffled tanks are hard to clean Baffles make the inside of the tank hard to clean, so sanitation rules keep them out of food tanks. (CDL manual: Tank Vehicles)

22. What is "outage"?

    1. The amount of liquid left after unloading
    2. Room left in the tank for the liquid to expand
    3. The time a tank is out of service
    4. A leak in a valve
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    B. Room left in the tank for the liquid to expand Liquids expand as they warm, so a tank is never loaded completely full. Different liquids need different amounts of outage. (CDL manual: Tank Vehicles)

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

    1. Full tanks cannot be unloaded
    2. Partly full tanks do not surge
    3. A full tank could go over legal weight limits
    4. Dense liquids do not expand
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    C. A full tank could go over legal weight limits A heavy liquid can put the vehicle over the legal weight limit well before the tank is full. (CDL manual: Tank Vehicles)

24. The amount of liquid to load into a tank depends on:

    1. What the shipper wants to send
    2. The weather forecast, the route and the time of day
    3. How much the liquid will expand, how much it weighs and legal weight limits
    4. The size of the fifth wheel only
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    C. How much the liquid will expand, how much it weighs and legal weight limits Expansion in transit, the weight of the liquid and legal weight limits together decide how much you can load. (CDL manual: Tank Vehicles)

25. To keep surge under control as you come to a stop, you should:

    1. Brake hard at the last moment
    2. Keep a steady pressure on the brakes and not release too soon
    3. Pump the brakes quickly
    4. Shift to neutral and coast
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    B. Keep a steady pressure on the brakes and not release too soon Steady pressure until the stop, without letting off early, keeps the liquid from shoving the truck. (CDL manual: Tank Vehicles)

26. Compared with other trucks, a tank driver approaching a stop should:

    1. Brake at the same point as a car
    2. Use only the engine brake
    3. Brake far in advance and leave a bigger following distance
    4. Follow more closely to save time
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    C. Brake far in advance and leave a bigger following distance Braking early and gently, with more space ahead, keeps the surge small and avoids sudden stops. (CDL manual: Tank Vehicles)

27. You must stop a tanker quickly to avoid a crash. What does the manual advise?

    1. Pull the trailer hand valve
    2. Use controlled or stab braking, and avoid steering quickly while braking
    3. Steer hard to one side first, then brake
    4. Jam the brakes on and hold them
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    B. Use controlled or stab braking, and avoid steering quickly while braking Controlled or stab braking keeps the wheels rolling. Quick steering while braking can roll a tank vehicle over. (CDL manual: Tank Vehicles; Driving Safely (quick stops))

28. With stab braking, after you release the brakes because the wheels locked, you apply them fully again:

    1. As soon as the wheels start rolling, which can take up to a second
    2. Only once the truck is straight
    3. Immediately, before the wheels roll
    4. After 5 seconds
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    A. As soon as the wheels start rolling, which can take up to a second Brakes all the way on, off when the wheels lock, back on when they roll again. Reapplying before they roll keeps the vehicle from straightening out. (CDL manual: Driving Safely (quick stops))

29. How should you drive a tank vehicle through a curve?

    1. Slow down before the curve, then accelerate slightly through it
    2. Brake in the middle of the curve
    3. Enter at the posted speed and brake if it leans
    4. Coast through in neutral
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    A. Slow down before the curve, then accelerate slightly through it Get the speed down before the curve and keep a slight acceleration through it. The posted speed may be too fast for a tanker. (CDL manual: Tank Vehicles)

30. A wet road can make your normal stopping distance:

    1. Shorter, because the tires cool
    2. About 10 percent longer
    3. About twice as long
    4. No different
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    C. About twice as long Wet roads can double stopping distance. Keep that in mind, along with the extra weight and surge of a tank load. (CDL manual: Tank Vehicles)

31. Compared with a full tank vehicle, an empty one:

    1. Always stops shorter
    2. May take longer to stop
    3. Has a higher center of gravity
    4. Cannot skid
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    B. May take longer to stop An empty vehicle has less weight on the tires and less traction, so the wheels lock more easily and the stop can take longer. (CDL manual: Tank Vehicles)

32. On a tank trailer, what can happen if the drive wheels or trailer wheels start to skid?

    1. The vehicle may jackknife
    2. The trailer brakes release
    3. The surge stops
    4. Nothing if the tank is baffled
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    A. The vehicle may jackknife Skidding wheels lose their grip and the rig can fold. Avoid over-steering, over-accelerating and over-braking, and act at once to get traction back. (CDL manual: Tank Vehicles)

33. An empty cargo tank that was used for hazardous materials reaches a railroad crossing. The driver must:

    1. Stop 15 to 50 feet from the tracks, look and listen, then cross without shifting
    2. Stop only if the lights are flashing
    3. Slow to 10 mph
    4. Cross without stopping because it is empty
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    A. Stop 15 to 50 feet from the tracks, look and listen, then cross without shifting Every cargo tank motor vehicle used for hazmat must stop at the tracks, loaded or empty. (49 CFR 392.10(a)(4))

34. While a cargo tank of hazardous material is loaded, the qualified person watching it must be within:

    1. 10 feet
    2. 100 feet
    3. 25 feet
    4. 50 feet
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    C. 25 feet Within 25 feet, alert, with a clear view of the tank, and able to move it if needed (unless an approved remote monitoring system is used). (49 CFR 177.834(i)(3))

35. A cargo tank still holds a small amount of hazardous material. Before you move it a short distance:

    1. The manhole may stay open to vent vapor
    2. All manholes and valves must be closed
    3. The valves may stay open for such a short trip
    4. Only the rear valve must be closed
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    B. All manholes and valves must be closed Manholes and valves must be closed no matter how little is in the tank or how short the move, unless the tank counts as empty under the rules. (49 CFR 177.834(j))