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 answer choices. To pass, the applicant must answer at least 20 questions correctly. Test questions come from the Rhode Island 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. Using the brakes creates heat. If too much heat is produced:
Explanation
Brakes are designed to take a lot of heat, but drivers should not rely solely on the brakes to slow their vehicle. Brakes may fade and lose their ability to slow down the vehicle if they become too hot, so drivers should also rely on the engine braking effect.
8. In a vehicle with dual air brakes, a leak in one system ____ the second system.
Explanation
A dual air brake system is made up of two separate air brake systems. If there is an air leak in one system, it may not affect the other.
9. If the low air pressure warning signal comes on, you should:
Explanation
If the low air pressure warning signal comes on while you are driving a vehicle with air brakes, you should immediately bring the vehicle to a safe stop while you are still able to control the brakes. Inspect and repair the brakes as soon as possible.
10. A dual air brake system:
Explanation
A dual air brake system is made up of two separate air brake systems. The systems share a single set of brake controls, but each has its own air tanks, hoses, and lines. One system typically operates the regular brakes on the rear axle or axles while the other system operates the regular brakes on the front axle.
11. During an applied leakage test, what is the maximum leakage rate that is safe for a single vehicle with air brakes?
Explanation
It is important to know the maximum air loss rate that is safe for your specific vehicle. A single vehicle with air brakes should have a leakage rate no higher than 3 psi in a minute during an applied leakage test.
12. Air pressure should build up in a single air system within:
Explanation
