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 does the round, yellow sign with a black border and a black 'X' posted ahead of a public rail crossing tell an approaching driver to do?

   Correct answer: Slow down, look and listen for a train, and be prepared to stop if one approaches

   The advance warning sign at a grade crossing directs you to ease off the throttle, watch and listen for a train, and be ready to halt at the rails if one is coming.

   Source: Colorado CDL Manual, Section 2.15.2 (Warning Signs and Devices)

2. 2. Painted on the roadway before many railroad crossings on two-lane roads, an 'X' with the letters 'RR' carries what meaning?

   Correct answer: It carries the same warning as the advance railroad sign to slow and prepare to stop

   These pavement markings deliver the same message as the round advance warning sign: reduce speed and be ready to stop for a train.

   Source: Colorado CDL Manual, Section 2.15.2 (Warning Signs and Devices)

3. 3. Among the required emergency warning devices a commercial vehicle must carry are reflective triangles. How many does the manual say to carry?

   Correct answer: Three reflective triangles

   The vehicle must have warning devices for a stopped vehicle: three reflective triangles, or at least six fusees, or three liquid-burning flares.

   Source: Colorado CDL Manual, Section 2.1.3 (What to Look For)

4. 4. A reflective red triangle with a bright orange center attached to the rear of a vehicle ahead is a signal that the vehicle is what?

   Correct answer: Designed to move much slower than surrounding traffic

   The slow-moving vehicle emblem warns other drivers that the vehicle travels well below normal traffic speed, so you should expect to close on it quickly.

   Source: Colorado CDL Manual, Section 2.8.3 (Drivers Who Are Hazards)

5. 5. Signs posted several miles from the top of a steep mountain downgrade often point out the location of what safety feature?

   Correct answer: An escape ramp for runaway vehicles

   Escape-ramp signs tell drivers where a runaway-vehicle ramp is located; the ramp uses a bed of loose, soft material to stop a truck safely.

   Source: Colorado CDL Manual, Section 2.16.4 (Proper Braking Technique)

6. 6. Under the hazard-class system used on placards, gasoline and acetone belong to which class?

   Correct answer: Class 3, flammable liquids

   Flammable liquids such as gasoline and acetone are grouped in Hazard Class 3.

   Source: Colorado CDL Manual, Section 2.23.2 (Hazard Class Definitions)

7. 7. A small sign mounted below a crossbuck showing a numeral such as '2' or '3' tells the driver what?

   Correct answer: The number of separate tracks the crossing covers

   When a crossing spans more than one set of rails, the sign beneath the crossbuck states how many tracks must be cleared.

   Source: Colorado CDL Manual, Section 2.15.2 (Warning Signs and Devices)

8. 8. A vehicle that is required to display hazardous-materials placards must carry how many, and where?

   Correct answer: Four matching diamond signs on the front, rear, and both sides

   Placarding rules require four identical diamond-shaped signs, mounted on the front, the rear, and both sides so the hazard is readable from every direction.

   Source: Colorado CDL Manual, Section 2.23.3 (Lists of Regulated Products)

9. 9. The warning lamp that tells a driver the antilock braking system has a fault is what color?

   Correct answer: Yellow

   Tractors, trucks, and buses show a yellow ABS malfunction lamp on the dash; on trailers the yellow lamp is on the left side.

   Source: Colorado CDL Manual, Section 2.18.3 (How to Know If Your Vehicle Is Equipped with ABS)

10. 10. Signs posted for 'move-over' laws direct approaching drivers to do what near a stopped emergency vehicle?

    Correct answer: Slow and move over to a lane away from the emergency vehicle when safe

    Move-over laws, marked by roadside signs, require drivers to slow down and, when it is safe, change into a lane not next to the stopped emergency vehicle or work area.

    Source: Colorado CDL Manual, Section 2.8.2 (Hazardous Roads)

11. 11. When descending a grade, what must a driver do about a posted 'Maximum Safe Speed' sign?

    Correct answer: Never travel faster than the speed shown on the sign

    A posted maximum-safe-speed figure on a downgrade must never be exceeded, and warning signs about the grade's length and steepness should also be heeded.

    Source: Colorado CDL Manual, Section 2.6.6 (Speed on Downgrades)

12. 12. The four-digit number shown on an orange panel or a placard on a cargo tank serves what purpose for emergency responders?

    Correct answer: It identifies the particular hazardous material being carried

    The identification number, preceded by 'NA' or 'UN', lets first responders look up the specific hazardous material in the Emergency Response Guidebook.

    Source: Colorado CDL Manual, Section 2.23.3 (Lists of Regulated Products)