Road Signs

Study questions with answers

12 sample Road Signs questions with the correct answer, a short explanation, and the official handbook reference. Read through them, then take the quiz above.

1. 1. What do flashing red lights at a highway-rail crossing tell you to do?

   Correct answer: Stop, because a train is approaching

   Flashing red lights mean a train is coming, so you must halt and let it pass first.

   Source: Utah CDL Manual — Section 2: Driving Safely (Flashing Red Light Signals)

2. 2. What color and shape is the advance warning sign placed ahead of a railroad crossing?

   Correct answer: A round, black-on-yellow sign

   The advance warning sign is round and black-on-yellow; it tells you to slow, look and listen for a train, and be ready to stop at the tracks.

   Source: Utah CDL Manual — Section 2: Driving Safely (Advance Warning Signs)

3. 3. How many identical placards must a placarded hazardous-materials vehicle display?

   Correct answer: Four

   A placarded vehicle must carry at least four identical placards, one on the front, one on the rear, and one on each side, readable from all directions.

   Source: Utah CDL Manual — Section 2: Driving Safely (Regulated Products)

4. 4. How do signs help a driver near a steep mountain downgrade?

   Correct answer: They mark escape ramp locations and warn of the grade

   Signs show where escape ramps are located and warn of the length and steepness of the grade so you can pick a safe speed and gear.

   Source: Utah CDL Manual — Section 2: Driving Safely (Escape Ramps)

5. 5. What shape must a hazardous materials placard be?

   Correct answer: A diamond turned upright on a point

   Placards are diamond-shaped signs, turned upright on a point, at least 250 mm (9.84 inches) square, placed on all four sides of the vehicle.

   Source: Utah CDL Manual — Section 2: Driving Safely (Regulated Products)

6. 6. What information does a diamond-shaped hazard label on a shipping package communicate?

   Correct answer: The risk posed by the material inside

   Shippers apply diamond hazard labels and papers so dock crews and drivers understand the danger a material carries.

   Source: Utah CDL Manual — Section 2: Driving Safely (Communicate the Risk)

7. 7. How does the round black-on-yellow railroad advance warning sign instruct you to react?

   Correct answer: Slow down, look and listen, and be ready to stop

   It signals you to ease off speed, watch and listen for a train, and be ready to halt at the rails if one nears.

   Source: Utah CDL Manual — Section 2: Driving Safely (Advance Warning Signs)

8. 8. What do the pavement markings before a railroad crossing consist of on a two-lane road?

   Correct answer: An 'X' with 'RR' and a no-passing marking

   These road markings carry the same message as the round advance sign: an 'X' paired with 'RR' letters plus a no-passing stripe.

   Source: Utah CDL Manual — Section 2: Driving Safely (Pavement Markings)

9. 9. What reference lists chemicals and their assigned identification numbers for first responders?

   Correct answer: The Emergency Response Guidebook

   First responders rely on the US DOT Emergency Response Guidebook, which pairs each regulated chemical with its assigned ID number.

   Source: Utah CDL Manual — Section 2: Driving Safely (Identification Numbers)

10. 10. The identification number on a hazardous-materials placard is preceded by which letters?

    Correct answer: 'NA' or 'UN'

    The four-digit identification number that first responders use is preceded by the letters 'NA' or 'UN'.

    Source: Utah CDL Manual — Section 2: Driving Safely (Identification Numbers)

11. 11. Hazard Class 3 placards identify which kind of material?

    Correct answer: Flammable liquids

    Hazard Class 3 covers flammable liquids, such as gasoline and acetone.

    Source: Utah CDL Manual — Section 2: Driving Safely (Hazard Class Definitions)

12. 12. A sign reading 'Maximum Safe Speed' on a downgrade tells a commercial driver what?

    Correct answer: Never exceed the speed shown

    Where a 'Maximum Safe Speed' sign is posted, you must never exceed the speed shown, and you should also heed warnings about the grade's length and steepness.

    Source: Utah CDL Manual — Section 2: Driving Safely (Speed on Downgrades)