Oregon CDL — General Knowledge practice
Road Signs
Learn the shapes, colors, and meanings of regulatory, warning, and guide signs — from stop and yield to construction and school-zone signs.
Content reviewed against official driver handbooks · July 7, 2026
14 questions · pass with 11 correct. You get instant feedback and an explanation after every answer.
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. How is the slow-moving vehicle emblem shaped and colored?
Correct answer: A red triangle with an orange center
The slow-moving vehicle symbol is a red triangle with an orange center, warning you that a vehicle ahead travels below normal speed.
Source: Oregon Commercial Driver Manual, Section 2.8.3 - Drivers Who Are Hazards
2. What should you do when you see a sign reading Maximum Safe Speed on a downgrade?
Correct answer: Never exceed the speed shown on the sign
If a Maximum Safe Speed sign is posted, you should never travel faster than the speed it shows.
Source: Oregon Commercial Driver Manual, Section 2.16.1 - Select a Safe Speed
3. What type of pavement marking appears on a two-lane road at a railroad crossing besides the RR letters?
Correct answer: A no-passing zone marking
In addition to the X and RR markings, a no-passing zone is marked on two-lane roads approaching the crossing.
Source: Oregon Commercial Driver Manual, Section 2.15.2 - Warning Signs and Devices
4. What does the round sign with a black symbol on a yellow background posted before a railroad crossing mean?
Correct answer: That a rail crossing is ahead and you should slow, look and listen
The circular yellow advance warning sign tells you to slow down, look and listen for a train, and be prepared to stop at the tracks.
Source: Oregon Commercial Driver Manual, Section 2.15.2 - Warning Signs and Devices
5. The identification number shown on a hazardous materials placard or panel is preceded by which letters?
Correct answer: The letters NA or UN
The four-digit identification number is preceded by the letters NA or UN so first responders can identify the material.
Source: Oregon Commercial Driver Manual, Section 2.23.3 - Lists of Regulated Products
6. What is the meaning of the crossbuck sign found at a highway-rail grade crossing?
Correct answer: You must yield the right-of-way to trains
The crossbuck marks the grade crossing and requires you to yield the right-of-way to any approaching train.
Source: Oregon Commercial Driver Manual, Section 2.15.2 - Warning Signs and Devices
7. What is the minimum size for a hazardous materials placard?
Correct answer: At least 9.84 inches (250 mm) on each side
Placards must be at least 9.84 inches (250 mm) on each side and displayed in a diamond shape standing on a point.
Source: Oregon Commercial Driver Manual, Section 2.23.3 - Lists of Regulated Products
8. From how many directions must hazardous materials placards be readable?
Correct answer: From all four directions
Placards must be readable from all four directions around the vehicle.
Source: Oregon Commercial Driver Manual, Section 2.23.3 - Lists of Regulated Products
9. What does the hazard-class placard on a vehicle tell other road users and responders?
Correct answer: The hazard class of the cargo being carried
A placard identifies the hazard class of the cargo being carried so others know the type of danger present.
Source: Oregon Commercial Driver Manual, Section 2.23.3 - Lists of Regulated Products
10. When a small sign is mounted below a crossbuck at a grade crossing, what does it tell you?
Correct answer: How many tracks the crossing has
When the roadway crosses more than one set of tracks, a sign beneath the crossbuck shows how many tracks are at the crossing.
Source: Oregon Commercial Driver Manual, Section 2.15.2 - Warning Signs and Devices
11. How many placards must a placarded hazardous materials vehicle display, and where?
Correct answer: At least four identical placards on the front, rear, and both sides
A placarded vehicle must carry at least four identical placards, mounted on the front, the rear, and both sides.
Source: Oregon Commercial Driver Manual, Section 2.23.3 - Lists of Regulated Products
12. At an advance-warning railroad sign, which vehicles are always required to stop?
Correct answer: Passenger buses and hazardous materials vehicles must stop
Buses carrying passengers and vehicles hauling hazardous materials are required to stop at railroad crossings.
Source: Oregon Commercial Driver Manual, Section 2.15.2 - Warning Signs and Devices
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Every Oregon question is written from the official Oregon driver handbook and checked against its current edition. DMV Test Free is a free, independent study resource — not affiliated with any DMV or government agency. About DMV Test Free