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CDL General Knowledge Test · CDL General Knowledge Test

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CDL General Knowledge Test Hazardous Materials Basics for All Drivers Summary

Importance
★★★☆☆ (3 / 5)
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About 2 of 50 CDL General Knowledge Test questions (4%)

What hazardous materials are, why the rules exist, shipping papers, placards and identification numbers, and when you need the hazardous materials endorsement.

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Hazardous Materials Basics for All Drivers: must-know points

  • You need the hazardous materials endorsement to drive any vehicle that requires placards.
  • A placarded vehicle needs at least four identical placards: front, rear, and both sides.
  • Keep hazardous materials shipping papers in a door pouch, in clear view within reach, or on the driver's seat when you are out of the vehicle.

Hazardous Materials Basics for All Drivers: 5 sample questions

Practice questionReviewedCDL General Knowledge Test › Hazardous Materials Basics for All Drivers★★★★☆

Question 1. When do you need a hazardous materials endorsement on your CDL?

  1. ① Any time you carry any amount of a hazardous material
  2. ② Only when you carry explosives
  3. ③ When you drive a vehicle that requires placards
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Answer: ③ When you drive a vehicle that requires placards

Key point: Placards required = hazmat endorsement

Not every vehicle with hazardous materials needs placards. If the vehicle requires placards, you must have the hazardous materials endorsement to drive it. Driving it without the endorsement is a crime.

Wrong choices

  • Any time you carry any amount of a hazardous material: You can carry some hazardous materials without placards and without the endorsement.
  • Only when you carry explosives: The rule covers all placarded loads, not only explosives.
Practice questionReviewedCDL General Knowledge Test › Hazardous Materials Basics for All Drivers★★★☆☆

Question 2. How many placards must a placarded vehicle display?

  1. ① At least four identical placards: front, rear, and both sides
  2. ② Two placards, one on each side
  3. ③ One placard on the rear
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Answer: ① At least four identical placards: front, rear, and both sides

Key point: Four placards, readable from all directions

A placarded vehicle must have at least four identical placards, on the front, rear, and both sides, so they can be read from all four directions. They are diamond shaped and at least 10 3/4 inches square.

Wrong choices

  • Two placards, one on each side: Placards must be readable from all four directions.
  • One placard on the rear: One placard cannot be read from the front or sides.
Practice questionReviewedCDL General Knowledge Test › Hazardous Materials Basics for All Drivers★★★☆☆

Question 3. You are carrying hazardous materials and get out of the cab. Where must the shipping papers be?

  1. ① Locked in the glove box
  2. ② On the driver's seat
  3. ③ In the sleeper berth
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Answer: ② On the driver's seat

Key point: Out of the cab: papers on the driver's seat

Hazardous materials shipping papers must be easy for responders to find. Keep them:

  • in a pouch on the driver's door, or
  • in clear view within reach while driving, or
  • on the driver's seat when you are out of the vehicle.

Wrong choices

  • Locked in the glove box: Responders may not find or open it.
  • In the sleeper berth: This is not one of the allowed places.
Practice questionReviewedCDL General Knowledge Test › Hazardous Materials Basics for All Drivers★★★☆☆

Question 4. What is a hazardous material identification number?

  1. ① The carrier's U.S. DOT number painted on the truck
  2. ② A two-letter code that shows the shipper's state
  3. ③ A four-digit number, shown after the letters UN or NA, that first responders use to identify the material
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Answer: ③ A four-digit number, shown after the letters UN or NA, that first responders use to identify the material

Key point: ID number: 4 digits after UN or NA

An identification number is a four-digit code, preceded by "UN" or "NA", that first responders use to identify hazardous materials. The U.S. DOT Emergency Response Guidebook lists the numbers.

Wrong choices

  • The carrier's U.S. DOT number painted on the truck: That number identifies the company, not the material.
  • A two-letter code that shows the shipper's state: It is a four-digit number, not a state code.
Practice questionReviewedCDL General Knowledge Test › Hazardous Materials Basics for All Drivers★★★☆☆

Question 5. Which of these is NOT one of the purposes of the hazardous materials rules?

  1. ① To lower shipping costs
  2. ② To contain the product
  3. ③ To communicate the risk
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Answer: ① To lower shipping costs

Key point: Hazmat rules: contain, communicate, ensure safety

The hazardous materials rules have three purposes: contain the product, communicate the risk, and ensure safe drivers and equipment. Lowering shipping costs is not one of them.

Wrong choices

  • To contain the product: Containing the product is one of the three purposes.
  • To communicate the risk: Communicating the risk is one of the three purposes.

Test yourself.

Hazardous Materials Basics for All Drivers: 5 questions →CDL General Knowledge Test: 5 questions →