Knowledge Test Class B #2
Class B Driving Test | District Of Columbia 2025 #2 Page 3 of 7
Train for FREE online with our District Of Columbia class B license test. The official exam test consists of several obligatory parts, with all of them checking your knowledge of different blocks of road rules. If you need to obtain a DC CDL class B permit in 2025, practice as much as possible. Free sample tests published on our website will help you check and improve your knowledge and boost your grades. Please bear in mind that CDL class B requirements may vary from state to state.
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15 . When an engine is started:
The hood must be open.
After a vehicle is started, the warning lights and buzzers should go out after a few seconds. If the warning signals do not turn off, there may be something wrong with the vehicle.
16 . Air tank drains:
Must remain open during transit.
In an air brake system, the air storage tanks must be drained to remove accumulated water and compressor oil. Failing to do so can cause damage. Manually operated drains should be used at the end of each day of driving.
17 . Federal and state laws require:
Drivers to inspect their vehicles, but only if they will be transporting hazardous materials.
Commercial drivers are required by federal and state laws to inspect their vehicles before every trip. Regular inspections can help drivers identify issues before they become dangerous and costly.
18 . Regarding winter driving, all of the following are true, except:
Use a gauge to verify that each tire has a safe tread depth.
When driving during the winter, it is particularly important that your tires have adequate tread. You need a tread depth of at least 4/32 of an inch in every major groove on the front tires, and at least 2/32 of an inch on the back tires. Check the tread depths by using a gauge.
19 . During an applied leakage test, the maximum leakage rate for a double combination vehicle is:
4 psi in a minute.
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.
20 . What is black ice?
Ice that is easily seen
Black ice is a thin layer of ice that is clear enough for the road surface to be seen through it. A road covered in black ice may look like it is merely wet.
21 . When a tire goes flat, you may hear a loud bang. The truck will be affected:
Only if the truck is hauling a load.
There may be a delay of a few seconds between the sound of a tire failing and the time that the vehicle is affected by the tire failure. Because of the short delay, a driver may initially believe that the sound came from another vehicle.
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2025 District Of Columbia | Frequently Asked Questions
In the District of Columbia, you can acquire a CDL Tank endorsement by first holding a valid CDL. You need to pass the Tank Vehicle written test, which covers topics like inspecting tank vehicles, driving tank vehicles, and safe driving rules. After passing the test, you pay the required fee to add the endorsement to your CDL.
To obtain a CDL Tank license in the District of Columbia, you must first have a valid Commercial Driver's License (CDL). Then, you must take and pass the Tank Vehicle written test, which covers topics such as inspecting and driving tank vehicles, and safe driving rules. After passing, pay the necessary fee to add the endorsement to your CDL.
While the District of Columbia doesn't explicitly require specific training or experience for a CDL Tank endorsement, it's highly recommended. Understanding how to safely operate tank vehicles is crucial. Passing the Tank Vehicle Endorsement Knowledge Test requires knowledge of tank vehicle operations, so training or experience can be beneficial in passing the test.
Yes, for a CDL Tank endorsement in the District of Columbia, you must pass the Tank Vehicle written test. This exam covers important topics like inspecting tank vehicles, driving tank vehicles, and safe driving rules. Passing this test is crucial to demonstrate your knowledge and understanding of operating tank vehicles safely.
The written test for the CDL Tank endorsement in the District of Columbia covers a variety of subjects. These include inspecting tank vehicles, driving tank vehicles, and understanding the unique handling characteristics of tank vehicles. It also tests knowledge on safe driving rules and regulations specific to tank vehicles.
During the CDL Tank endorsement assessment, several skills and maneuvers are assessed. These include inspecting the tank vehicle for safety, demonstrating proper loading and unloading procedures, controlling the vehicle's speed and position, performing backing maneuvers, and executing turns and lane changes safely. Additionally, candidates are evaluated on their ability to handle emergency situations and demonstrate knowledge of hazardous materials regulations.
Drivers with a CDL Tank endorsement in the District of Columbia must comply with specific federal and state regulations. These include restrictions on maximum driving hours to prevent fatigue, mandatory rest periods, and stringent vehicle inspection requirements. Additionally, they must follow rules related to the transportation of hazardous materials if their tank vehicle is used for such purposes.
No, a valid CDL Tank endorsement is required to legally transport liquid or gas materials in the District of Columbia. This endorsement is necessary due to the unique handling and safety requirements associated with transporting such materials. Violating this requirement can result in significant penalties, including fines and suspension of driving privileges.
You can add the CDL Tank endorsement to your existing Commercial Driver's License (CDL) without needing a fresh application. However, you will need to pass a written knowledge test specific to tank vehicles and pay the necessary endorsement fee. Remember, additional endorsements may require further testing.
Yes, to handle hazardous materials with a CDL Tank endorsement, you must also obtain a Hazardous Materials (HazMat) endorsement. This requires passing an additional written test and undergoing a federal background check. Also, adherence to specific regulations regarding the transportation and handling of such materials is mandatory.
