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CDL Endorsement Practice Tests: Hazmat, Tanker, Doubles, Passenger, School Bus

Hazardous materials, tank vehicles, doubles and triples, passenger and school bus endorsement knowledge tests.

160 questions · 5 topics · free, no sign-up

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Mixed practice test

10 questions, graded as you go, with the reason for every answer. No sign-up.

Practise by topic

Sample questions

Which combination has the greatest rearward amplification?

  1. A set of doubles
  2. A tractor-semitrailer
  3. A straight truck
  4. A set of triples
Show the answer

D. A set of triples

Rearward amplification grows with the number of trailers and articulation points, so triples have the most. A straight truck has none because it has no trailer.

Reference: AAMVA CDL Manual, Section 6.1 and 7.1

A shipper offers you a drum of corrosive liquid that is seeping at the bung. What should you do?

  1. Load it upright near the rear doors
  2. Wrap it in plastic and then load it
  3. Accept it if the papers mention it
  4. Refuse to accept the leaking drum
Show the answer

D. Refuse to accept the leaking drum

Drivers must refuse leaking packages and shipments. Wrapping the drum or noting the leak on the paperwork does not make it safe or legal to carry; the shipper has to correct the packaging.

Reference: AAMVA CDL Manual, Section 9.2; 49 CFR 177.801

When may an emergency roof hatch be left partly open?

  1. Never, under any conditions at all
  2. Only while the bus is parked and empty
  3. Whenever riders ask the driver for it
  4. For fresh air, though not as a regular practice
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D. For fresh air, though not as a regular practice

Emergency exits must be closed while driving, with one exception: some roof hatches may be locked partly open for fresh air. Do not make a habit of it, and remember the bus's higher clearance with the hatch open.

Reference: AAMVA CDL Manual, Section 4.1

How far can the danger zone extend out from the left and right sides of a school bus?

  1. 3 feet
  2. 5 feet
  3. 10 feet
  4. 20 feet
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C. 10 feet

The danger zones extend about 10 feet from each side and 10 feet behind the rear bumper. In front they may extend as much as 30 feet, with the first 10 feet the most dangerous.

Reference: AAMVA CDL Manual, Section 10.1

What do bulkheads do in a liquid tank?

  1. Let liquid flow slowly between sections
  2. Strengthen it against outside impacts
  3. Vent vapors from the top of the load
  4. Divide it into separate smaller tanks
Show the answer

D. Divide it into separate smaller tanks

Solid bulkheads split the tank into separate compartments. The dividers that have holes to let liquid pass are baffles, which is the usual mix-up.

Reference: AAMVA CDL Manual, Section 8.2

Exams this helps with

ExamWho runs itWhere
Doubles and triples endorsement (T)State DMVsUnited States
Hazardous materials endorsement (H)State DMVs, TSAUnited States
Passenger endorsement (P)State DMVsUnited States
School bus endorsement (S)State DMVsUnited States
Tank vehicles endorsement (N)State DMVsUnited States

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