CDL Hazmat Endorsement Practice Test
Updated October 27, 2026
To haul hazardous materials that require placards, you need the H endorsement. That means a Hazardous Materials knowledge test, usually 30 questions with 80% to pass, plus a TSA security threat assessment, and the hazmat training must be finished before you take the knowledge test. Try the free questions below.
These answers follow the model CDL manual most states use. Check your state’s manual for any differences.
The nine hazard classes
| Class | Material |
|---|---|
| 1 | Explosives |
| 2 | Gases |
| 3 | Flammable liquids |
| 4 | Flammable solids |
| 5 | Oxidizers and organic peroxides |
| 6 | Poisons (toxic) and infectious substances |
| 7 | Radioactive |
| 8 | Corrosives |
| 9 | Miscellaneous hazardous materials |
Free CDL Hazmat practice questions
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Which hazard class covers flammable liquids such as gasoline?Answer: CClass 3 is flammable liquids, such as gasoline. Class 2 is gases, Class 4 is flammable solids and Class 8 is corrosives.
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While driving, where must the shipping papers for hazardous materials be kept?Answer: DShipping papers must be within your reach while you're buckled in, or in a pouch on the driver's door, so emergency responders can find them. When you leave the vehicle, leave them on the driver's seat or in the door pouch.
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What does a placard on a vehicle do?Answer: APlacards are diamond-shaped signs on all four sides of the vehicle that warn others, including emergency responders, which hazards are on board.
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How close to a vehicle carrying explosives, flammable materials or oxidizers may you smoke?Answer: BNever smoke, or carry a lit cigarette, cigar or pipe, within 25 feet of a vehicle carrying Class 1 explosives, Division 2.1 flammable gases, Class 3 flammable liquids, Class 4 flammable solids or Class 5 oxidizers.
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Before you can take the Hazardous Materials knowledge test, what must you have completed?Answer: CUnder federal entry-level driver training rules, the hazmat training must be finished before you take the Hazardous Materials knowledge test. You also need a TSA security threat assessment to get the endorsement.
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Which document helps responders find what to do in the first minutes of a hazmat incident?Answer: DThe Emergency Response Guidebook, from the U.S. Department of Transportation, tells first responders how to protect themselves and the public in the initial phase of a hazmat incident. Shipping papers must also include emergency response information.
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Which hazard class is corrosive materials, such as battery acid?Answer: CClass 8 is corrosives. Class 3 is flammable liquids, Class 5 oxidizers and organic peroxides, and Class 9 miscellaneous hazardous materials.
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How many placards must a vehicle display when placards are required?Answer: DPlacarded vehicles must display placards on all four sides: front, rear and both sides.
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Placards are required for materials in the "Table 2" list once the total amount reaches:Answer: ATable 1 materials require placards in any amount. Table 2 materials require placards when the total is 1,001 pounds or more (with some exceptions in the regulations).
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Who is responsible for preparing the shipping papers and certifying that hazardous materials are properly packaged and labeled?Answer: BThe shipper prepares the shipping papers and certifies that materials are properly classified, packaged, marked and labeled. The driver checks them and makes sure the vehicle is properly placarded.
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How must hazardous materials be identified on shipping papers that also list non-hazardous items?Answer: CHazardous materials must stand out on mixed shipping papers: listed first, highlighted, or marked with an X (or RQ) in the HM column.
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A placarded vehicle approaches a railroad crossing. What must the driver do?Answer: DPlacarded vehicles must stop 15 to 50 feet from the nearest rail, look and listen, and cross without changing gears.
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If a fire occurs in a trailer carrying hazardous materials, what should the driver avoid?Answer: AOpening the doors lets in air that can feed the fire. Keep the doors closed, warn others and call for help.
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What does "RQ" mean on a shipping paper?Answer: BRQ means reportable quantity. If that amount or more is spilled or released, it must be reported to the proper authorities.
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Which hazard class covers explosives?Answer: CClass 1 is explosives. Class 2 is gases, Class 4 flammable solids, and Class 7 radioactive materials.
Tips
Hazmat questions lean on rules, so read the hazardous materials section of your state’s CDL manual carefully. Learn the hazard classes, when placards are required, where shipping papers must be kept and what to do in an emergency.
Pass your CDL permit test on the first try
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