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Tanker Practice Question 21

NTanker · Question 21

The 'two-thirds rule' for loading flammable liquids is:

• AAlways fill exactly 2/3
• BLeave outage of about 2% per 10°F warming the liquid will undergo
• CDriver works 2 of 3 days
• DCharge 2/3 of capacity

Correct answer: B. Leave outage of about 2% per 10°F warming the liquid will undergo

Why: Liquids expand with temperature. The required outage depends on the liquid and temperature differences expected. The exact outage is calculated from the product specs.

How this question fits the Tanker test

Liquid surge can push a vehicle through an intersection or roll it on a curve. The Tanker endorsement specifically addresses how unbaffled and partially full tanks behave differently from rigid loads.

Study technique for this topic

Know the difference between baffled, unbaffled, and compartmented tanks, the safe outage percentage for liquid expansion, and why front-to-back surge is more dangerous than side-to-side surge.

Related Tanker practice questions

• Q40. A tank with a recent product change should:
• Q53. The most dangerous moment in a tanker rollover sequence is when:
• Q3. A 'baffle' inside a tank is:
• Q16. Liquid surge can:
• Q30. The first rule when starting a downhill grade with liquid is:

Continue your CDL preparation

The Tanker portion of the CDL knowledge exam covers more than this single question. Use this site's full Tanker bank to drill every topic, then test yourself with one of our state-specific practice sets to confirm you are ready for the actual DMV exam in your state. Always check your state's CDL handbook for any local addenda before the test day.

If you are still building your overall CDL foundation, start with the General Knowledge bank — every CDL applicant must pass it — and then work outward to the endorsements you plan to add.