A CDL-required truck is designed to carry water in one permanently mounted 1,500-gallon tank. Can it be a tank vehicle even though the water is not hazardous?
Correct answer: Yes; the tank definition is not limited to hazardous liquids or gases.
The definition covers liquid or gaseous material in qualifying tanks. Tank-vehicle endorsement requirements are separate from whether a hazardous-material endorsement is also needed.
Source: 49 CFR 383.5, definition of Tank vehicle; 383.93(b)(3); Official eCFR XML dated September 11, 2026 checked against the linked rule; reviewed September 15, 2026. ↗
A CDL-required truck is designed to transport liquid in two attached tanks rated 150 and 850 gallons. Do these capacities meet the federal tank-vehicle capacity thresholds?
Correct answer: Yes; each exceeds 119 gallons and together they total 1,000 gallons.
The definition uses individual rated capacity greater than 119 gallons and aggregate rated capacity at least 1,000 gallons. Permanent and temporary attachment can both qualify.
Source: 49 CFR 383.5, definition of Tank vehicle; Official eCFR XML dated September 11, 2026 checked against the linked rule; reviewed September 15, 2026. ↗
A CDL-required truck carries liquid in ten attached tanks, each rated exactly 119 gallons. Do those tanks meet the individual-capacity condition in the federal tank-vehicle definition?
Correct answer: No; the individual rated capacity must be more than 119 gallons.
Although their total exceeds 1,000 gallons, exactly 119 gallons does not satisfy the more-than 119 individual threshold. This answer concerns the tank definition, not exemption from other CDL or cargo rules.
Source: 49 CFR 383.5, definition of Tank vehicle; Official eCFR XML dated September 11, 2026 checked against the linked rule; reviewed September 15, 2026. ↗
A CMV carries an empty 1,500-gallon storage-container tank that is not designed for transportation and is temporarily attached to a flatbed. How does the federal tank definition treat this specific case?
Correct answer: It excludes that specified empty storage-container movement from tank-vehicle classification.
The definition has a narrow exception for this empty storage-container situation. It does not apply to every empty transport tank or remove unrelated requirements.
Source: 49 CFR 383.5, definition of Tank vehicle, final sentence; Official eCFR XML dated September 11, 2026 checked against the linked rule; reviewed September 15, 2026. ↗
Why should a driver consult the operator’s manual when inspecting an unfamiliar tank vehicle?
Correct answer: Tank designs and special equipment vary, so the inspection must fit that vehicle.
The handbook requires tank-specific checks in addition to normal vehicle inspection. Know the vehicle’s equipment before loading, unloading or driving.
Source: Maryland Commercial Driver’s License Manual, DL-151 (02/26), February 2026; Section 8, 8.1; Tank-specific inspection instructions; physical PDF page 209 (printed 209); public mirror of the Maryland manual; reviewed September 15, 2026. ↗
You find liquid leaking from the tank shell before loading is complete. What is the proper response?
Correct answer: Stop the unsafe operation and have the leak addressed before carrying the load.
Do not carry liquid or gas in a leaking tank. Follow the appropriate emergency and repair procedures for the material and do not improvise a containment or repair method.
Source: Maryland Commercial Driver’s License Manual, DL-151 (02/26), February 2026; Section 8, 8.1.1; Leaking tank; physical PDF page 209 (printed 209); public mirror of the Maryland manual; reviewed September 15, 2026. ↗
Before loading, unloading or moving a tanker, what must you verify about its intake, discharge and cutoff valves?
Correct answer: They are in the correct positions for the operation being performed.
Different operations require the proper valve configuration. Verify the actual system’s instructions; driving with open discharge valves is not a safe shortcut.
Source: Maryland Commercial Driver’s License Manual, DL-151 (02/26), February 2026; Section 8, 8.1.1; Valve positions; physical PDF page 210 (printed 210); public mirror of the Maryland manual; reviewed September 15, 2026. ↗
Where should a tanker driver pay particular attention when checking pipes, hoses and connections for leakage?
Correct answer: Around joints and connection points.
Joints and connections are important potential leak points. Inspect the whole system rather than assuming an undamaged tank shell means the plumbing is sound.
Source: Maryland Commercial Driver’s License Manual, DL-151 (02/26), February 2026; Section 8, 8.1.1; Hose-joint inspection; physical PDF page 210 (printed 210); public mirror of the Maryland manual; reviewed September 15, 2026. ↗
What should be checked about tank manhole covers?
Correct answer: Their gaskets are present and the covers close correctly.
Correctly sealed covers help contain the cargo. Designed venting must remain functional; an open cover is not a substitute for a proper vent system.
Source: Maryland Commercial Driver’s License Manual, DL-151 (02/26), February 2026; Section 8, 8.1.1; Manhole sealing; physical PDF page 210 (printed 210); public mirror of the Maryland manual; reviewed September 15, 2026. ↗
Why must tank vents be kept clear and functional?
Correct answer: They must perform their designed venting function.
Inspect vents as part of the tank system and follow the equipment’s instructions. Blocking them or substituting an open cover can create an unsafe condition.
Source: Maryland Commercial Driver’s License Manual, DL-151 (02/26), February 2026; Section 8, 8.1.1; Tank vents; physical PDF page 210 (printed 210); public mirror of the Maryland manual; reviewed September 15, 2026. ↗
A tanker is equipped with an emergency shut-off system. What should be established before operating it?
Correct answer: That the system is present, functional and understood by the driver.
Check fitted emergency equipment and learn how it operates. The necessary equipment and procedure depend on the tank and material; this quiz does not replace operational training.
Source: Maryland Commercial Driver’s License Manual, DL-151 (02/26), February 2026; Section 8, Check Special Purpose Equipment; Emergency shut-off equipment; physical PDF page 210 (printed 210); public mirror of the Maryland manual; reviewed September 15, 2026. ↗
Which fitted equipment requires checking as part of tank-vehicle inspection?
Correct answer: Grounding or bonding cables and vapor-recovery equipment, when provided.
The handbook lists vapor recovery, grounding and bonding, emergency shut-offs and built-in fire extinguishers among equipment to check when fitted.
Source: Maryland Commercial Driver’s License Manual, DL-151 (02/26), February 2026; Section 8, Check Special Purpose Equipment; Special-purpose equipment; physical PDF page 210 (printed 210); public mirror of the Maryland manual; reviewed September 15, 2026. ↗
