Knowledge Test Class B #1
Class B Driving Test | District Of Columbia 2025 #1 Page 6 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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36 . While driving, spring brakes are generally held in place by:
Sturdy ties.
While driving, spring brakes are generally held in place by air pressure. If the air pressure gets low enough, the springs will activate the brakes.
37 . To make driving at night easier, you should:
Use only your low beam headlights.
If the interior of your cab is too bright when you are driving at night, you may have difficulty seeing things outside. Keep the interior light off and adjust your instrument lights to the lowest possible level that still allows you to easily read the gauges.
38 . Which of the following is not an example of a driving hazard?
An ice cream truck
Passing an accident scene can be hazardous because the people involved in the accident may not be watching traffic, and the scene itself may distract other passing drivers. Ice cream trucks can create hazardous conditions because they attract children who may not pay attention to nearby vehicles. Shoppers near the roadway are often paying attention to stores, not passing traffic.
39 . Which of the following is a good rule to follow when making a turn?
Signal early.
Signal well in advance of a turn so drivers behind you are aware of your intentions. Keep the signal on throughout the turn and turn it off once the turn is complete.
40 . During the vehicle inspection test, you will be asked to:
Change a windshield wiper.
During the CDL vehicle inspection test, you must be able to inspect your vehicle and explain to the examiner what you are inspecting and why.
41 . You may be denied a HazMat endorsement if:
You do not suffer from a mental illness.
You will be denied a HazMat endorsement, or lose an existing endorsement, if you are not a lawful permanent U.S. resident; you renounce your U.S. citizenship; you are wanted for, under indictment for, or convicted of certain felonies; you are judged as mentally unstable or are committed to a mental institution; or you are deemed to pose a security threat by the Transportation Security Administration (TSA).
42 . What should happen if the air pressure in the braking system's air tanks falls below 60 psi?
The steering wheel will lock up.
On vehicles with air brakes, a low air pressure warning signal will come on if the pressure in the air tanks falls below 60 psi. On large buses, the signal may activate at 80 to 85 psi.
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2025 District Of Columbia | Frequently Asked Questions
A CDL Class B license in the District of Columbia authorizes the holder to operate vehicles with a Gross Vehicle Weight Rating (GVWR) of 26,001 pounds or more, or any such vehicle towing another not in excess of 10,000 pounds. This includes buses, dump trucks, delivery trucks, and other medium to heavy commercial vehicles.
A Class B CDL license in the District of Columbia allows the holder to operate single vehicles with a Gross Vehicle Weight Rating of 26,001 pounds or more, or any such vehicle towing another not exceeding 10,000 pounds. This includes buses, dump trucks, segmented buses, delivery trucks, and utility trucks.
To acquire a Class B CDL license in District of Columbia, you must be at least 21 years old, possess a valid DC driver's license, pass a vision test, and complete a commercial driver's license application. You'll also need to pass a general knowledge test and a skills test, which includes a pre-trip vehicle inspection, a basic control skills test, and an on-road driving test.
In the District of Columbia, you must be at least 21 years old to qualify for a Class B CDL license. This is the age requirement set by the Federal Motor Carrier Safety Administration for interstate travel. However, some states may allow individuals aged 18 and above to drive within that state's borders.
While not always necessary, specific endorsements can expand the types of vehicles you can operate with a Class B CDL license in the District of Columbia. These include passenger vehicles (P), school buses (S), and tank vehicles (N). Each endorsement requires additional testing.
The Class B CDL skills assessment in the District of Columbia encompasses three main parts: a pre-trip vehicle inspection, a basic vehicle control test, and an on-road driving test. These tests assess your ability to inspect your vehicle, control its basic functions, and drive it safely on the road.
Yes, Class B CDL license holders in the District of Columbia are limited to operating vehicles with a Gross Vehicle Weight Rating (GVWR) of 26,001 pounds or more. They can also tow trailers that weigh less than 10,000 pounds. They cannot operate Class A vehicles without the appropriate endorsement.
Yes, in the District of Columbia, the written Class B CDL test is available in several languages other than English. However, federal regulations require all CDL holders to read and speak English sufficiently to converse with the general public, understand highway traffic signs and signals, respond to official inquiries, and make entries on reports and records.
Yes, in the District of Columbia, test accommodations for people with disabilities are available for the Class B CDL written exam. You can request accommodations through the DC Department of Motor Vehicles. However, you need to provide supporting documentation of your disability to qualify for these accommodations.
Yes, if you don't pass the Class B CDL written test in the District of Columbia, you can retake it. However, you must wait at least three business days before retesting. If you fail six times within a year, you'll have to wait one year from the date of the last test before retaking it.