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CDL HazMat EndorsementPart 3 of 3

CDL HazMat Endorsement Exam Questions & Answers 2026 (21–30)

CDL HazMat Endorsement practice questions and answers 2026. Tap an option to test yourself — you'll see the correct answer and a plain-English explanation for every question. Free, no login.

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  1. Q21Under 49 CFR 173.136, a substance is classified as Class 8 (Corrosive) based on its ability to cause what specific effect?

    • AFull-thickness destruction of intact skin tissue within a specified observation period, or a corrosion rate on steel or aluminum exceeding a defined threshold
    • BLowering the flash point of a mixture to below 73°F when blended with flammable liquids
    • CEmission of toxic vapors that exceed the IDLH concentration at the point of release
    • DImmediate ignition of combustible materials on contact at ambient temperature
    Show answer

    ✓ Correct answer: A. Full-thickness destruction of intact skin tissue within a specified observation period, or a corrosion rate on steel or aluminum exceeding a defined threshold

    49 CFR 173.136 defines Class 8 corrosives as liquids or solids that cause full-thickness destruction of intact skin tissue within a set observation period, or that show a corrosion rate on steel or aluminum exceeding 6.25 mm per year at 55°C in standardized testing.

  2. Q22A driver is transporting a material labeled as Class 9 (Miscellaneous Hazardous Material). According to 49 CFR 173.155, which of the following is the MOST accurate description of Class 9?

    • AMaterials that combine two or more hazard classes into a single placard category
    • BMaterials that present a hazard during transport but do not meet the definition of any other hazard class, including elevated-temperature materials, magnetized materials, and environmentally hazardous substances
    • CMaterials exclusively regulated by the EPA rather than DOT during ground transport
    • DMaterials that are non-regulated and require no placarding under any circumstances
    Show answer

    ✓ Correct answer: B. Materials that present a hazard during transport but do not meet the definition of any other hazard class, including elevated-temperature materials, magnetized materials, and environmentally hazardous substances

    49 CFR 173.155 defines Class 9 (Miscellaneous) as materials that present a hazard during transport that is not covered by Classes 1–8, including lithium batteries, dry ice, elevated-temperature materials, magnetized materials, and marine pollutants — all of which require the Class 9 placard when thresholds are met.

  3. Q23Where must a commercial motor vehicle driver keep shipping papers for hazardous materials while driving?

    • AWithin reach while the driver's seat belt is fastened, or in a pouch on the driver's door
    • BIn the glove compartment or locked storage box
    • CFiled with the motor carrier's dispatcher before departure
    • DAttached to the outside of the cargo door nearest the load
    Show answer

    ✓ Correct answer: A. Within reach while the driver's seat belt is fastened, or in a pouch on the driver's door

    Under 49 CFR 177.817(e), shipping papers must be within the driver's reach while the seat belt is fastened, or in a pouch on the driver's door, so they are immediately accessible for inspection or emergency response.

  4. Q24Which of the following pieces of information is NOT required to appear on a shipping paper for a hazardous material?

    • AThe UN or NA identification number
    • BThe proper shipping name
    • CThe hazard class or division number
    • DThe shipper's net profit margin for the shipment
    Show answer

    ✓ Correct answer: D. The shipper's net profit margin for the shipment

    49 CFR 172.202 requires the proper shipping name, hazard class or division, identification number, and packing group on shipping papers, but financial data such as profit margin has no regulatory basis and is never required.

  5. Q25What is the correct order of the basic description on a hazardous materials shipping paper when listing a single hazardous material entry?

    • APacking group, proper shipping name, ID number, hazard class
    • BProper shipping name, hazard class, ID number, packing group
    • CHazard class, ID number, proper shipping name, packing group
    • DID number, proper shipping name, hazard class, packing group
    Show answer

    ✓ Correct answer: D. ID number, proper shipping name, hazard class, packing group

    49 CFR 172.202(a) specifies that the basic description must appear in this sequence: identification number, proper shipping name, hazard class or division, and packing group — in that exact order.

  6. Q26When a vehicle is not attended by the driver, where must shipping papers for hazardous materials be kept?

    • ALocked inside the vehicle cab at all times
    • BVisible from outside the vehicle through the windshield
    • CAttached to the cargo trailer's exterior in a weatherproof sleeve
    • DIn a pouch on the driver's door or on the driver's seat
    Show answer

    ✓ Correct answer: D. In a pouch on the driver's door or on the driver's seat

    Per 49 CFR 177.817(e), when the driver is not in the vehicle the shipping papers must be in a holder on the inside of the driver's door or on the driver's seat so emergency responders can find them quickly.

  7. Q27A driver is transporting a mix of hazardous and non-hazardous materials on the same bill of lading. How must the hazardous materials entries be identified so they stand out from the non-hazardous entries?

    • AThey must be entered in a different font size that is at least twice as large
    • BThey must carry the shipper's USDOT registration number printed next to each entry
    • CThey must be highlighted in a contrasting color, asterisked, or entered before all non-hazardous entries
    • DThey must appear on a completely separate document from the non-hazardous items
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    ✓ Correct answer: C. They must be highlighted in a contrasting color, asterisked, or entered before all non-hazardous entries

    49 CFR 172.201(a)(1) requires that hazardous materials entries on a mixed shipping paper be distinguished from non-hazardous entries by highlighting, an identifying color, an asterisk, or by being listed before all non-hazardous entries.

  8. Q28A shipper prepares a shipping paper for 'Flammable Liquid, n.o.s.' containing toluene and xylene. Which additional requirement applies to this n.o.s. entry?

    • AThe technical names of at least the two most hazardous constituents must appear in parentheses after the proper shipping name
    • BThe packing group may be omitted since the entry is already listed as n.o.s.
    • CThe flash point in degrees Fahrenheit must be printed immediately after the hazard class
    • DThe shipper must attach a Material Safety Data Sheet in place of the standard description
    Show answer

    ✓ Correct answer: A. The technical names of at least the two most hazardous constituents must appear in parentheses after the proper shipping name

    Under 49 CFR 172.203(k), for n.o.s. and other generic proper shipping names, the technical names of at least two constituents most predominately contributing to the hazard must be entered in parentheses in association with the basic description.

  9. Q29Which statement correctly describes the shipper's certification that must appear on a hazardous materials shipping paper?

    • AIt must be signed by the receiving carrier's terminal manager upon acceptance of the freight
    • BIt must be notarized by a state-licensed official before the shipment may move in interstate commerce
    • CIt declares that the shipper has prepared the shipment in proper condition per applicable regulations and that the material is properly classified, described, packaged, marked, and labeled
    • DIt is only required for Class 1 explosives and Class 7 radioactive materials
    Show answer

    ✓ Correct answer: C. It declares that the shipper has prepared the shipment in proper condition per applicable regulations and that the material is properly classified, described, packaged, marked, and labeled

    49 CFR 172.204(a) requires the offeror (shipper) to sign a certification stating that the hazardous material is properly classified, described, packaged, marked, and labeled, and is in proper condition for transportation in accordance with applicable regulations.

  10. Q30A driver picks up a shipment of Division 2.1 (flammable gas) and later adds a stop with a non-hazardous freight pickup. The new bill of lading does not list any hazardous materials. What must the driver do regarding the original hazardous materials shipping papers?

    • ADiscard the old papers since the newer bill of lading supersedes them
    • BRetain the original hazardous materials shipping papers and keep them accessible throughout the trip
    • CTransfer the hazardous materials description onto the new bill of lading and destroy the original
    • DForward the original papers to the next carrier by fax before departing the new pickup location
    Show answer

    ✓ Correct answer: B. Retain the original hazardous materials shipping papers and keep them accessible throughout the trip

    49 CFR 177.817 requires that shipping papers accompany the hazardous materials for the entire trip; adding non-hazardous freight does not eliminate the obligation to retain and keep accessible the original hazardous materials shipping papers.

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