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Hazardous Materials (Hazmat) Practice Question 21

H or XHazardous Materials (Hazmat) · Question 21

Class 7 hazardous materials are:

• ACorrosives
• BRadioactive materials
• COxidizers
• DToxic

Correct answer: B. Radioactive materials

Why: Class 7 covers radioactive materials. Different sub-types (Type A, Type B packaging) and yellow placards II/III mark the radiation level.

How this question fits the Hazmat test

Mishandled hazmat causes catastrophic public consequences. The endorsement is restricted, requires fingerprint background screening through the TSA, and demands deeper familiarity with regulatory paperwork than any other CDL endorsement.

Study technique for this topic

Master the Hazardous Materials Table columns, know the placarding thresholds, and learn which classes can never be loaded together. Practice locating UN/NA identification numbers and understanding the segregation chart.

Related Hazmat practice questions

• Q30. When parking a placarded hazmat vehicle, you generally may not park within:
• Q43. Loading hazmat into a vehicle requires:
• Q56. When loading explosives, the cargo space must be:
• Q5. Some hazardous materials require placards in any quantity. These are listed in:
• Q18. Class 4 hazardous materials are:

Continue your CDL preparation

The Hazardous Materials (Hazmat) portion of the CDL knowledge exam covers more than this single question. Use this site's full Hazardous Materials (Hazmat) 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.