Hazmat (HazMat Endorsement) for the CDL Exam

Common failure modes

These are the patterns that cause most candidates to lose marks on this topic. Recognising them in advance is half the work.

• !Confusing the nine UN hazard classes and their division numbers
• !Misidentifying when placards are required (any quantity for Table 1 materials)
• !Forgetting to check the shipping paper, placards, and labels match before driving
• !Not knowing the segregation rules between incompatible classes (e.g., Class 1.1 explosives must not load with Class 5.1 oxidisers)

Study tips

• 1Memorize the nine hazard classes by example, not number: explosives, gases, flammable liquids, flammable solids, oxidisers, toxics, radioactive, corrosives, miscellaneous.
• 2Drill Table 1 vs Table 2 placarding rules — Table 1 (e.g., 1.1 explosives) requires placards at any amount.
• 3Practice the proper sequence after an incident: secure scene, separate, send for help — the "3 S's".
• 4Know the emergency phone-number requirement on the shipping paper (24-hour reachable).

Sample CDL Hazmat (HazMat Endorsement) questions

These sample items mirror the format and difficulty of real CDL questions. Practice with thousands more on the free Koydo question bank.

1. 1

   Which of the following materials requires placards at any amount?

   • AClass 3 — Flammable Liquid
   • BClass 1.1 — Mass ExplosivesCorrect
   • CClass 8 — Corrosive
   • DClass 9 — Miscellaneous
   Why this answer?

   Class 1.1, 1.2, and 1.3 explosives appear on Table 1 of the placarding rules and require placards regardless of quantity. Other materials use the Table 2 threshold of 1,001 lbs aggregate gross weight.

2. 2

   The shipping paper must list the material's identification number in what location?

   • AOn the front cover only
   • BWithin easy reach of the driver while drivingCorrect
   • CIn the trailer
   • DFiled with TSA before departure
   Why this answer?

   The HMR requires the driver to keep the shipping paper within reach while behind the wheel and in plain view (placed on the seat or in a door pouch) while away from the vehicle.