U.S. CDL · HAZMAT · QUESTIONS & ANSWERS

U.S. CDL Hazardous Materials Practice — questions and answers

All 30 original Rig Toolbox practice questions for this test, printed in full with the correct answer and an explanation for each one. Read them here, then put them to work in Practice or the Exam Simulator — no sign-up, ever.

Start Practice Exam Simulator Quick Review

Independent practice: these are Rig Toolbox's own study questions, not official exam questions. Always confirm rules in the official handbook for the licence you are taking.

About this question set

How many questions are here? 30 — the full bank for this test. The interactive test draws 20 of them at a time.

What is this test? Original hazardous-materials practice based on the hazmat section of state CDL manuals and the federal hazmat rules.

Every question, with its answer

Question 1

To drive a vehicle carrying materials that require placards, a driver must hold:

  1. A passenger endorsement
  2. Any CDL
  3. Only a medical card
  4. A CDL with a hazardous materials endorsement, which includes a TSA security threat assessment

Correct answer: A CDL with a hazardous materials endorsement, which includes a TSA security threat assessment

The HME requires passing the hazmat knowledge test and clearing the federal TSA background check and fingerprinting.
Question 2

Which job belongs to the SHIPPER of hazardous materials?

  1. Identifying the material, packing, marking and labelling it, and preparing and certifying the shipping papers
  2. Setting the driver’s schedule
  3. Inspecting the truck’s brakes
  4. Driving the load to its destination

Correct answer: Identifying the material, packing, marking and labelling it, and preparing and certifying the shipping papers

The shipper classifies, packages, marks, labels and certifies the shipment; the carrier and driver take it from there.
Question 3

Which job belongs to the DRIVER before moving a hazmat load?

  1. Printing the labels
  2. Choosing the hazard class
  3. Confirming the shipment is properly described, marked and labelled, checking for leaks, and making sure the right placards are in place
  4. Writing the shipper’s certification

Correct answer: Confirming the shipment is properly described, marked and labelled, checking for leaks, and making sure the right placards are in place

The driver verifies papers, packages and placards, refuses damaged or leaking items, and keeps the load safe in transit.
Question 4

While you are driving, where must the hazmat shipping papers be?

  1. Within your immediate reach while restrained by the seat belt, such as in the driver’s door pouch
  2. In the trailer with the cargo
  3. Under the cargo
  4. In the carrier’s office

Correct answer: Within your immediate reach while restrained by the seat belt, such as in the driver’s door pouch

Papers must be reachable at the controls while driving; when you leave the vehicle they go on the driver’s seat or stay in the door pouch where officials can see them.
Question 5

A hazmat shipping description on the papers must include:

  1. The consignee’s phone number only
  2. Only the driver’s name
  3. The price of the load
  4. The identification (UN/NA) number, proper shipping name, hazard class or division, and packing group if any

Correct answer: The identification (UN/NA) number, proper shipping name, hazard class or division, and packing group if any

The basic description identifies the material by number, name, class and packing group so responders know what they face.
Question 6

How many placards must a placarded vehicle display, and where?

  1. Four: front, rear and both sides
  2. Two: both doors
  3. As many as the shipper likes
  4. One, on the back

Correct answer: Four: front, rear and both sides

Placards go on all four sides so the warning can be read from any direction.
Question 7

How large is a standard hazmat placard?

  1. About 24 inches square
  2. About 4 inches square
  3. About 10.8 inches (273 mm), square-on-point
  4. Size does not matter

Correct answer: About 10.8 inches (273 mm), square-on-point

Placards are diamond-shaped signs 10.8 inches on each side; package labels are the smaller 4-inch diamonds.
Question 8

Materials in Placard Table 1 (for example Division 1.1 explosives and Division 2.3 poison gas) require placards:

  1. Only in bulk tanks
  2. At any quantity
  3. Never
  4. Only over 1,001 pounds

Correct answer: At any quantity

Table 1 materials are dangerous enough that any amount carried requires placarding.
Question 9

For Placard Table 2 materials, placards are required when the aggregate gross weight of the load reaches:

  1. 1,001 pounds
  2. 100 pounds
  3. 5,000 pounds
  4. 500 pounds

Correct answer: 1,001 pounds

Table 2 categories need placards once the combined gross weight of all Table 2 materials is 1,001 pounds or more.
Question 10

You are offered a hazmat package that is leaking. What must you do?

  1. Tape over the leak and go
  2. Refuse the shipment; a leaking package must not be accepted or moved
  3. Load it where it cannot be seen
  4. Load it last

Correct answer: Refuse the shipment; a leaking package must not be accepted or moved

Drivers must refuse leaking or otherwise improper hazmat packages; moving them is illegal and dangerous.
Question 11

Smoking is prohibited within how many feet of a vehicle loaded with explosives or flammable materials during loading and unloading?

  1. 10 feet
  2. 5 feet
  3. 100 feet
  4. 25 feet

Correct answer: 25 feet

Keep cigarettes, matches and open flames at least 25 feet away from these loads.
Question 12

When fueling a vehicle carrying hazardous materials, you must:

  1. Disconnect the battery
  2. Fuel only at night
  3. Keep the engine running
  4. Turn the engine off and keep someone in control of the nozzle

Correct answer: Turn the engine off and keep someone in control of the nozzle

Engines stay off during fueling of hazmat vehicles, and the nozzle is never left unattended.
Question 13

A vehicle transporting placarded hazardous materials must carry a fire extinguisher with a minimum UL rating of:

  1. 10 B:C
  2. 5 B:C
  3. 1 A only
  4. No extinguisher is required

Correct answer: 10 B:C

Hazmat vehicles need at least a 10 B:C rated extinguisher, higher than the standard vehicle requirement.
Question 14

How often must a driver check the tires on a vehicle hauling hazardous materials?

  1. At the start of the trip and at every stop
  2. Never; tires are the shipper’s job
  3. Once a week
  4. Only when a tire looks flat

Correct answer: At the start of the trip and at every stop

Tire checks at departure and each stop are a specific hazmat rule, and a failed tire must be repaired properly before continuing.
Question 15

Which hazmat loads require the driver to stop at every railroad crossing?

  1. Only loads under 100 pounds
  2. None; stops are optional
  3. Vehicles that are placarded (and cargo tanks and buses under their own rules)
  4. Only empty vehicles

Correct answer: Vehicles that are placarded (and cargo tanks and buses under their own rules)

Placarded vehicles must stop at railroad crossings, check both ways, and proceed only when safe (unless an exempt sign applies).
Question 16

When parking a vehicle loaded with Division 1.1, 1.2 or 1.3 explosives, you must not park within 300 feet of:

  1. Bridges, tunnels, buildings or places where people gather, and the vehicle must not be left unattended except in a safe haven
  2. Another empty truck
  3. A truck stop
  4. Any farm

Correct answer: Bridges, tunnels, buildings or places where people gather, and the vehicle must not be left unattended except in a safe haven

Explosives loads need distance from structures and crowds, and attendance or an approved safe haven.
Question 17

When a hazmat vehicle must legally be attended, the attendant must:

  1. Be a member of the public
  2. Be awake and alert, within 100 feet of the vehicle with a clear view of it, and know the hazards and emergency steps
  3. Be asleep in the sleeper berth
  4. Be anywhere reachable by phone

Correct answer: Be awake and alert, within 100 feet of the vehicle with a clear view of it, and know the hazards and emergency steps

Attendance means close, awake supervision by someone who understands the load and what to do in an emergency.
Question 18

Which route choice is best for a long hazmat trip?

  1. Any route a passenger car would take
  2. Routes that avoid heavily populated areas, crowds, tunnels and narrow streets where possible, following any state routing rules
  3. The most crowded downtown streets
  4. The shortest route no matter what it passes

Correct answer: Routes that avoid heavily populated areas, crowds, tunnels and narrow streets where possible, following any state routing rules

Planning avoids places where an incident would harm the most people, and some states designate hazmat routes.
Question 19

If you find a hazmat leak at a stop with no fire, your first actions are to:

  1. Park in a safe place, secure the area, keep people away and upwind, and notify your carrier
  2. Wash it into a drain
  3. Drive quickly to the destination
  4. Cover it with dirt and say nothing

Correct answer: Park in a safe place, secure the area, keep people away and upwind, and notify your carrier

Contain the scene by distance and information: no driving with a growing leak, no contact with the material, help called early.
Question 20

Near a flammable hazmat spill or vehicle, warning devices used must be:

  1. Burning flares for visibility
  2. Reflective triangles, never open-flame flares
  3. No devices at all
  4. The four-way flashers only

Correct answer: Reflective triangles, never open-flame flares

Open flames can ignite vapours; use reflective warning devices around flammables.
Question 21

What is the Emergency Response Guidebook (ERG) used for?

  1. Replacing shipping papers
  2. Logging driving hours
  3. Looking up a material by name or ID number to get first-response safety actions
  4. Finding fuel prices

Correct answer: Looking up a material by name or ID number to get first-response safety actions

The ERG gives responders the first steps for each material; keep it with the shipping papers.
Question 22

After a serious hazmat incident (for example a spill that closes a road or injures someone), the carrier must:

  1. Forget it if the load still arrived
  2. Only tell the consignee
  3. Give immediate telephone notice to the National Response Center and file a written incident report
  4. Wait until the next inspection

Correct answer: Give immediate telephone notice to the National Response Center and file a written incident report

Certain incidents require immediate phone notification and a written follow-up report on the official form.
Question 23

Why must some hazardous materials never be loaded together in the same vehicle?

  1. They always have the same labels
  2. They take up too much room
  3. Some materials react dangerously with each other; the segregation chart shows which combinations are forbidden
  4. It is only about paperwork

Correct answer: Some materials react dangerously with each other; the segregation chart shows which combinations are forbidden

Incompatible materials, such as cyanides and acids, are kept apart using the federal segregation table.
Question 24

How must compressed gas cylinders be transported?

  1. Secured upright or braced in racks, with valves protected by caps
  2. Lying loose on the floor
  3. With the valves removed
  4. Stacked three high

Correct answer: Secured upright or braced in racks, with valves protected by caps

Cylinders must be held so they cannot fall or roll, and valve protection caps stay on during transport.
Question 25

When loading Division 1.1 or 1.2 explosives, you must:

  1. Use metal hooks to move the packages faster
  2. Turn the engine off and handle packages gently, with no dropping, throwing or hook use
  3. Load them on top of flammable liquids
  4. Keep the engine running for the lights

Correct answer: Turn the engine off and handle packages gently, with no dropping, throwing or hook use

Explosives demand gentle handling and a shut-down engine; rough handling or sparks can be catastrophic.
Question 26

Vehicles hauling chlorine in cargo tanks must carry:

  1. An approved gas mask and an emergency kit for controlling leaks in the tank fittings
  2. A spare placard
  3. Nothing special
  4. Only a fire extinguisher

Correct answer: An approved gas mask and an emergency kit for controlling leaks in the tank fittings

Chlorine is a poison gas; the manual requires a gas mask and the dome-fitting emergency kit on the vehicle.
Question 27

The four-digit identification number for a hazmat load must be displayed:

  1. On placards, orange panels, or the white square-on-point background for bulk packages
  2. Only in the driver’s log
  3. On the mud flaps
  4. It is never displayed

Correct answer: On placards, orange panels, or the white square-on-point background for bulk packages

Bulk shipments show the UN/NA number on orange panels or on the placard so responders can identify the material from a distance.
Question 28

Gasoline carried in bulk is an example of which hazard class?

  1. Class 9 miscellaneous only
  2. Class 1 explosives
  3. Class 7 radioactive
  4. Class 3 flammable liquids

Correct answer: Class 3 flammable liquids

Gasoline is the textbook Class 3 flammable liquid.
Question 29

Sulfuric acid in a cargo tank is an example of which hazard class?

  1. Class 6 toxic only
  2. Class 4 flammable solids
  3. Class 8 corrosive materials
  4. Class 2 gases

Correct answer: Class 8 corrosive materials

Acids and caustics are Class 8 corrosives; they destroy skin and attack metal.
Question 30

Before moving any hazmat vehicle, the driver must make sure that:

  1. Only the rear placard is needed
  2. The placards match the load described on the shipping papers and are readable from all four sides
  3. The papers are locked in the trailer
  4. The load is hidden from view

Correct answer: The placards match the load described on the shipping papers and are readable from all four sides

Papers and placards must agree and be in place before the wheels turn; in an emergency a vehicle may be moved only to a safe place.

Ready to try them for real?

Start Practice Exam Simulator Quick Review

More questions & answers

Every Rig Toolbox practice bank, printed in full with answers: