For a vehicle requiring a CDL, which attached liquid or gas tank capacities meet the federal tank-vehicle definition?
Correct answer: Each qualifying tank exceeds 119 gallons; combined capacity is at least 1,000 gallons
Use rated capacities, not just the amount currently loaded. Permanent and temporary attachments qualify. An empty storage container tank not designed for transportation, temporarily attached to a flatbed, has a specific exception. Tank vehicles require the tank endorsement; hazardous cargo can require additional authorization.
Source: 49 CFR 383.5, Tank vehicle definition; endorsement requirement in 383.93(b)(3), current eCFR checked September 12, 2026 ↗
What cargo restriction applies to a commercial learner permit holder with a tank endorsement?
Correct answer: The tank must be empty and any previous hazardous-material residue purged
An N-endorsed CLP permits only an empty tank vehicle. A tank that previously contained hazardous material must be purged of residue. Other CLP conditions, including the qualified accompanying CDL holder, still apply.
Source: 49 CFR 383.25(a)(5)(iii), empty tanks and hazardous-material residue; accompanying driver in (a)(1), checked September 12, 2026 ↗
Which cargo-tank defect can make it unsafe to transport a load?
Correct answer: A leaking valve or tank seam
Leaks can make the vehicle unlawful and unsafe to move and can leave the driver responsible for cleanup.
Source: Florida Commercial Driver's License Manual, July 2022, section 8.1.1 Leaks, printed page 8-8-1 (as printed) (physical PDF page 107) ↗
What should a driver do after discovering that a cargo tank is leaking?
Correct answer: Do not transport cargo in it
A leaking tank must not be driven with cargo; doing so is a crime and the vehicle can be placed out of service.
Source: Florida Commercial Driver's License Manual, July 2022, section 8.1.1 Leaks, printed page 8-8-1 (as printed) (physical PDF page 107) ↗
Before loading, unloading, or moving a tank vehicle, what must be verified about its valves?
Correct answer: They are in the correct positions
Intake, discharge, and cutoff valves must be checked for leaks and set correctly for the operation.
Source: Florida Commercial Driver's License Manual, July 2022, section 8.1.1 Leaks, valves, printed page 8-8-1 (as printed) (physical PDF page 107) ↗
What should be checked at tank manhole covers and vents?
Correct answer: Sound gaskets, correctly closed covers, clear vents
Secure gasketed covers prevent leaks, while clear vents must remain able to function.
Source: Florida Commercial Driver's License Manual, July 2022, section 8.1.1 Leaks, manhole covers and vents, printed page 8-8-1 (as printed) (physical PDF page 107) ↗
Which system is special-purpose tanker equipment that must work when installed?
Correct answer: Emergency shutoff system
Vapor recovery, grounding and bonding cables, emergency shutoffs, and built-in extinguishers require inspection.
Source: Florida Commercial Driver's License Manual, July 2022, section 8.1.2 Check Special Purpose Equipment, printed page 8-8-1 (as printed) (physical PDF page 107) ↗
Which cargo-tank condition must be corrected before travel?
Correct answer: Open discharge valve or manhole cover
A tank vehicle must never be driven with valves or manhole covers open.
Source: Florida Commercial Driver's License Manual, July 2022, section 8.1.2 Check Special Purpose Equipment, printed page 8-8-1 (as printed) (physical PDF page 107) ↗
Why are liquid tankers especially vulnerable to rollover?
Correct answer: Their load has a high center of gravity
Much of the load weight is high above the road, making the vehicle top-heavy.
Source: Florida Commercial Driver's License Manual, July 2022, section 8.2.1 High Center of Gravity, printed page 8-8-1 (as printed) (physical PDF page 107) ↗
How should a tanker driver approach highway, entrance-ramp, and exit-ramp curves?
Correct answer: Well below the posted curve speed
Tankers can roll even at posted curve speeds, so the driver must reduce speed well below them.
Source: Florida Commercial Driver's License Manual, July 2022, section 8.2.1 High Center of Gravity, printed page 8-8-1 (as printed) (physical PDF page 107) ↗
What can liquid surge do after a partly filled tanker stops on a slippery road?
Correct answer: Shove the stopped vehicle forward
A moving liquid wave can strike the tank end and shove the vehicle in the wave direction.
Source: Florida Commercial Driver's License Manual, July 2022, section 8.2.2 Danger of Surge (continued), printed page 8-8-2 (as printed) (physical PDF page 108) ↗
When loading a tank divided into separate compartments by bulkheads, what deserves special attention?
Correct answer: Front-to-rear weight distribution
Separate compartments can overload the front or rear if their weight is distributed poorly.
Source: Florida Commercial Driver's License Manual, July 2022, section 8.2.3 Bulkheads, printed page 8-8-2 (as printed) (physical PDF page 108) ↗
What movement do baffles primarily help control?
Correct answer: Forward-and-back liquid surge
Holes in baffles reduce longitudinal surge; dangerous side-to-side movement remains possible.
Source: Florida Commercial Driver's License Manual, July 2022, section 8.2.4 Baffled Tanks, printed page 8-8-2 (as printed) (physical PDF page 108) ↗
Why must starts and stops be especially gentle with a smooth-bore tanker?
Correct answer: Nothing inside the tank slows the liquid flow
An unbaffled smooth-bore tank permits strong forward-and-back surge.
Source: Florida Commercial Driver's License Manual, July 2022, section 8.2.5 Un-baffled Tanks, printed page 8-8-2 (as printed) (physical PDF page 108) ↗
Why are some food-product tanks built without baffles?
Correct answer: Baffles can make the inside difficult to clean to sanitation standards
Sanitation requirements can rule out baffles because they complicate interior cleaning.
Source: Florida Commercial Driver's License Manual, July 2022, section 8.2.5 Un-baffled Tanks, printed page 8-8-2 (as printed) (physical PDF page 108) ↗
What does outage mean when loading a liquid cargo tank?
Correct answer: Empty space left for the liquid to expand
Liquids expand as they warm, so the tank must not be filled completely.
Source: Florida Commercial Driver's License Manual, July 2022, section 8.2.6 Outage, printed page 8-8-2 (as printed) (physical PDF page 108) ↗
Which three factors does Florida handbook section 8.2.7 list for deciding how much liquid to load?
Correct answer: Expansion in transit, liquid weight, and legal weight limits
Allow expansion space and respect cargo weight and legal limits. Available tank volume alone does not determine a safe load.
Source: Florida Commercial Driver's License Manual, July 2022, section 8.2.7 How Much to Load?, printed page 8-8-2 (as printed) (physical PDF page 108) ↗
Why might a large tank be only partly filled with a dense liquid?
Correct answer: A full tank could exceed legal weight limits
Tank volume does not override weight limits; dense products can make a full tank overweight.
Source: Florida Commercial Driver's License Manual, July 2022, section 8.2.7 How Much to Load?, printed page 8-8-2 (as printed) (physical PDF page 108) ↗
Which driving pattern is safest for a loaded tanker?
Correct answer: Smooth starts, gradual stops, gentle turns, and steady lane changes
Smooth control limits surge and rollover forces created by the high center of gravity.
Source: Florida Commercial Driver's License Manual, July 2022, section 8.3.1 Drive Smoothly, printed page 8-8-2 (as printed) (physical PDF page 108) ↗
How should a tanker driver brake for a planned stop?
Correct answer: Brake well in advance with steady pressure and extra following distance
Early, steady braking and more following room help keep surge controlled.
Source: Florida Commercial Driver's License Manual, July 2022, section 8.3.2 Controlling Surge, printed page 8-8-2 (as printed) (physical PDF page 108) ↗
For a tanker without ABS, which emergency braking methods does the handbook describe?
Correct answer: Controlled or stab braking
For a tanker without ABS, section 8.3.2 describes controlled or stab braking for an emergency stop. Sudden steering while braking can overturn a tanker. This question does not instruct drivers to pump functioning ABS brakes.
Source: Florida Commercial Driver's License Manual, July 2022, section 8.3.2 Controlling Surge, printed page 8-8-2 (as printed) (physical PDF page 108) ↗
What is the recommended speed-control sequence for a curve in a tank vehicle?
Correct answer: Slow before the curve, then accelerate slightly through it
Reducing speed before entry avoids heavy braking while turning; slight acceleration through the curve improves control.
Source: Florida Commercial Driver's License Manual, July 2022, section 8.3.3 Curves, printed page 8-8-2 (as printed) (physical PDF page 108) ↗
Which tanker may require more stopping distance than many drivers expect?
Correct answer: An empty tank vehicle
An empty tanker can need more stopping distance than a loaded one. Wet pavement further increases stopping distance; allow extra space instead of assuming an empty vehicle will stop quickly.
Source: Florida Commercial Driver's License Manual, July 2022, section 8.3.4 Stopping Distance, printed page 8-8-2 (as printed) (physical PDF page 108) ↗
Which action can cause a tank vehicle to skid?
Correct answer: Oversteering, hard acceleration, or excessive braking
Abrupt steering, acceleration, and braking can break tire traction.
Source: Florida Commercial Driver's License Manual, July 2022, section 8.3.5 Skids, printed page 8-8-2 (as printed) (physical PDF page 108) ↗
What can happen if the drive or trailer wheels of a tank trailer begin to skid?
Correct answer: The combination may jackknife
A skid at the drive or trailer wheels can start a jackknife, so the driver must restore wheel traction.
Source: Florida Commercial Driver's License Manual, July 2022, section 8.3.5 Skids, printed page 8-8-2 (as printed) (physical PDF page 108) ↗
