Air Brakes
This endorsement is required for driving a vehicle with air brakes. To receive this endorsement, applicants must pass a written test. The test consists of 25 multiple choice questions. Each question has three or four answer choices. To pass, the applicant must answer at least 20 questions correctly. Test questions come from the Nevada Commercial Driver License Manual. Questions come from the chapter covering: Air Brakes. The Air Brakes endorsement may be used with the Class A, B or C CDL.
Number of Question
Passing Score
7. When traveling down a steep downgrade, the best way to use your brakes is to:
Explanation
On a long or steep downgrade, brakes should only be used to supplement the braking effect of the engine. Apply the brakes just enough to feel a definite slowing down, then release them once you are about 5 mph below your target "safe" speed. Once your vehicle reaches its safe speed again, repeat this process.
8. The air entering air storage tanks may contain:
Explanation
The air that enters air storage tanks in an air brake system usually contains a certain amount of water and compressor oil. Because accumulations of these materials can damage the braking system, tanks are equipped with drains to allow their removal.
9. Air tank drains should:
Explanation
Compressed air in an air brake system usually contains a certain amount of water and compressor oil. The water and oil can damage the brakes if left to accumulate in the system. Manually operated air tank drains must be opened daily to remove this build-up.
10. During an applied leakage test, the maximum leakage rate for a double combination vehicle is:
Explanation
It is important to know the maximum air loss rate that is safe for your specific vehicle. A double combination vehicle should have a leakage rate no higher than 4 psi in a minute during an applied leakage test.
11. If a vehicle has air brakes, the air compressor drive belt should be checked before each drive. In what condition should the belt be?
Explanation
When inspecting a vehicle with air brakes that has a belt-driven air compressor, you should check the condition and tightness of the belt. It should be in good condition.
12. If the air pressure warning light comes on, you should:
Explanation
