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Hazardous Materials (Hazmat) Practice Question 40

H or XHazardous Materials (Hazmat) · Question 40

A 'subsidiary risk' label indicates:

• AA material has a primary and additional hazard
• BA backup carrier
• CA maintenance issue
• DA fuel additive

Correct answer: A. A material has a primary and additional hazard

Why: Some materials have a primary hazard plus a secondary risk (e.g., flammable liquid that is also corrosive). Subsidiary labels appear in addition to the primary.

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

• Q52. Labeling refers to:
• Q1. The Hazardous Materials Regulations are found in:
• Q14. The driver must be familiar with the contents of the:
• Q27. A driver discovering a leak in a hazmat shipment should:
• Q41. Under what condition can a driver leave a hazmat vehicle unattended?

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.