25 realistic Hazardous Materials practice questions for Ohio CDL applicants. Required for: Drivers transporting placarded hazardous materials. Official test: 30 questions, 24 correct to pass.
Question 1 of 25 · HazMat Driving
When transporting HazMat over long distances, drivers should:
-
A.
Stay alert, take rest breaks, and inspect the load regularly
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B.
Drive at maximum speed limit
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C.
Skip rest stops to save time
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D.
Avoid highways
Correct answer: A.
Stay alert with regular rest breaks; inspect cargo at every stop.
Question 2 of 25 · CDL Rules
What does the letter "H" represent on a CDL?
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A.
Hazardous materials endorsement
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B.
Heavy vehicle endorsement
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C.
Highway driving endorsement
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D.
Hauling endorsement
Correct answer: A.
The H endorsement allows a CDL holder to transport placarded hazardous materials.
Question 3 of 25 · Security
Which of these is part of the carrier's security plan?
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A.
Personnel security
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B.
Unauthorized access prevention
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C.
En-route security
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D.
All of the above
Correct answer: D.
Carrier security plans cover personnel checks, access controls, and en-route security.
Question 4 of 25 · Shipping Papers
Where must HazMat shipping papers be kept while loading or unloading?
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A.
In the cab only
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B.
On the dock with the cargo
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C.
On the seat of the cab or in a door pouch within reach
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D.
Locked in the glove box
Correct answer: C.
Papers must be readily accessible at all times during transport.
Question 5 of 25 · Placards
What does each placard show?
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A.
The hazard class number
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B.
A pictorial symbol for the hazard
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C.
The four-digit ID number when required
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D.
All of the above
Correct answer: D.
Placards show the hazard class number, symbol, and ID number when required.
Question 6 of 25 · HazMat Basics
What's the most important reason for these regulations?
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A.
Public safety
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B.
Protect the environment
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C.
Protect the carrier
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D.
All of the above
Correct answer: D.
Regulations protect people, property, and the environment.
Question 7 of 25 · Loading
Which of these can never be hauled with explosives?
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A.
Cyanides or other toxic substances
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B.
Building materials
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C.
Foodstuffs
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D.
Newspapers
Correct answer: A.
Cyanides, certain other poisons, and other incompatible substances cannot be loaded with explosives.
Question 8 of 25 · Loading
You should turn off your engine when:
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A.
Loading or unloading flammable liquids
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B.
Driving on a hill
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C.
Inspecting brakes
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D.
Refueling on the highway
Correct answer: A.
Turn off the engine when loading or unloading flammable liquids to reduce ignition risk.
Question 9 of 25 · Rail Crossings
What is the maximum stopping distance allowed for HazMat vehicles approaching a railroad crossing?
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A.
Stop within 15-50 feet of the nearest rail and not closer than 15 feet
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B.
Stop on the tracks
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C.
Stop only when train is approaching
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D.
No stop required
Correct answer: A.
HazMat vehicles must stop 15 to 50 feet from the nearest rail before crossing.
Question 10 of 25 · Security
Which is true about HazMat training?
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A.
Drivers must be retrained every 3 years
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B.
Training is optional
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C.
Only new drivers need training
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D.
Training is the same as for non-HazMat
Correct answer: A.
HazMat training is required every three years, including security awareness.
Question 11 of 25 · HazMat Driving
When transporting Class 1 explosives, the driver must:
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A.
Park anywhere convenient
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B.
Have a written route plan and follow it
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C.
Drive only at night
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D.
Drive only on local roads
Correct answer: B.
Drivers must have a route plan and avoid populated areas where possible.
Question 12 of 25 · Emergencies
What is the first thing you should do if your HazMat load catches fire?
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A.
Pull over, away from buildings or vehicles, then call 911
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B.
Drive to the nearest hospital
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C.
Continue to destination
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D.
Try to put it out with snow
Correct answer: A.
Stop in a safe place, away from people and buildings, then notify emergency services.
Question 13 of 25 · Tank Operations
Which of these are dangers of hauling liquids in tanks?
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A.
Liquid surge
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B.
Outage requirements
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C.
Top-heavy load
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D.
All of the above
Correct answer: D.
Surge, outage, and high center of gravity all make tank vehicles uniquely dangerous.
Question 14 of 25 · HazMat Driving
When can drivers smoke around a HazMat vehicle?
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A.
While driving only
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B.
When parked at a truck stop
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C.
Never within 25 feet of certain materials
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D.
Whenever convenient
Correct answer: C.
Smoking is forbidden within 25 feet of HazMat including explosives, oxidizers, or flammables.
Question 15 of 25 · Placards
Yellow placards generally indicate:
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A.
Flammable solids
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B.
Oxidizers
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C.
Corrosives
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D.
Radioactive materials
Correct answer: B.
Yellow placards usually indicate oxidizers.
Question 16 of 25 · Emergencies
Drivers must report HazMat incidents to:
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A.
The local newspaper
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B.
Carrier and law enforcement, then the National Response Center
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C.
No one — drivers are not responsible
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D.
The shipper only
Correct answer: B.
Notify your carrier and local responders, then call the National Response Center if reportable.
Question 17 of 25 · Loading
What does "blasting agents" refer to?
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A.
Materials used to detonate explosives
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B.
A class of explosives sensitive to ignition
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C.
Cleaning agents
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D.
Aerosol propellants
Correct answer: A.
Blasting agents are materials designed to be set off using a detonator.
Question 18 of 25 · Loading
What is "containment"?
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A.
Putting HazMat in proper packaging
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B.
A type of placard
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C.
Stopping leaks during transport
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D.
Containing fumes inside the trailer
Correct answer: A.
Containment means using packaging that meets DOT specifications for the material being shipped.
Question 19 of 25 · Emergencies
When a HazMat package leaks, you should:
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A.
Move it to a safe area
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B.
Secure the area and call for help
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C.
Continue the trip
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D.
Place it in the trailer's rear
Correct answer: B.
Don't move leaking packages. Secure the area and contact qualified responders.
Question 20 of 25 · HazMat Driving
Which is true about smoking near HazMat vehicles?
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A.
Smoking is fine while driving
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B.
Smoking is prohibited within 25 feet of certain materials
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C.
Smoking is allowed at truck stops
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D.
Smoking is allowed in residential areas
Correct answer: B.
Smoking is forbidden within 25 feet of explosives, oxidizers, and flammables.
Question 21 of 25 · Shipping Papers
HazMat shipping papers must be:
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A.
Out of the driver's reach
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B.
Within the driver's reach while driving and clearly distinguished from other shipping papers
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C.
In the trailer with the cargo
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D.
Mailed to the receiver in advance
Correct answer: B.
Shipping papers must be within reach and identifiable. They must be on the seat or in a door pouch.
Question 22 of 25 · Placards
Placards are warning signs placed on:
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A.
Drivers' shirts
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B.
The outside of vehicles transporting HazMat
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C.
The shipping papers only
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D.
Inside the cab
Correct answer: B.
Diamond-shaped placards on the four sides of the vehicle warn others of hazardous cargo.
Question 23 of 25 · Loading
What is "compatibility group letter"?
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A.
A code that tells which explosives can be loaded together
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B.
A type of placard
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C.
A type of vehicle
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D.
A type of safety vest
Correct answer: A.
Letters such as "A," "B," etc., classify explosives that can be transported together.
Question 24 of 25 · Emergency Equipment
Which of the following is a sign of a tire fire?
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A.
Smoke from the tire
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B.
A loud noise
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C.
Vibration in the steering
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D.
All of the above
Correct answer: D.
Watch for smoke, noise, and vibration as warning signs of a tire fire.
Question 25 of 25 · Parking
Some HazMat vehicles cannot be parked within how many feet of a bridge, tunnel, or building?
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A.
100 feet
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B.
200 feet
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C.
300 feet
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D.
500 feet
Correct answer: C.
Class 1 (explosives) generally must not be parked within 300 feet of bridges, tunnels, or buildings.
About the Hazardous Materials Test
The Hazardous Materials (HazMat) test covers the rules for transporting materials that pose a risk to health, safety, and property. Topics include the hazardous materials table, shipping papers, marking, labeling, placarding, loading and unloading, bulk packaging, driving and parking rules, communications, emergencies, and hazardous materials regulations enforced by the U.S. Department of Transportation Pipeline and Hazardous Materials Safety Administration. A federal Transportation Security Administration (TSA) background check is also required.
The Ohio Bureau of Motor Vehicles administers this knowledge test as part of its commercial driver license program. To earn the HazMat Endorsement (H) on your Ohio CDL, you need to score at least 24 out of 30 on the official version.
Topics covered on this practice test
- Loading: 5 questions
- HazMat Driving: 4 questions
- Placards: 3 questions
- Emergencies: 3 questions
- Security: 2 questions
- Shipping Papers: 2 questions
- CDL Rules: 1 question
- HazMat Basics: 1 question
- Rail Crossings: 1 question
- Tank Operations: 1 question
- Emergency Equipment: 1 question
- Parking: 1 question
How to use this practice test
- Read each question carefully. CDL questions are written precisely — small wording differences matter.
- Click "Show Answers & Explanations" only after answering every question. Don't peek mid-test.
- Read the explanation for every question, even ones you got right. The reasoning is more important than the answer.
- Repeat the test until you score 100%. The questions are deterministic per state, so you can track your improvement over multiple sessions.
- Move on to the other endorsement tests for Ohio until you're ready for the official exam.
Tips specific to the Hazardous Materials test
HazMat is the longest knowledge test (30 questions) and adds a Transportation Security Administration (TSA) background check. Most candidates struggle with placard colors, the segregation table, shipping paper requirements, and emergency response procedures. Use the official Emergency Response Guidebook (ERG) alongside this practice set.