PennDOT Commercial Driver's License

Question 1

What should you always check during a pre-trip inspection?

Accepted Answer

The condition of the windshield wipers

Answer

A pre-trip inspection is a critical safety measure to identify potential hazards before driving. Checking the condition of windshield wipers ensures clear visibility, which is essential for safe operation, especially in adverse weather conditions, and is a standard component of a thorough vehicle check.

Question 2

When driving a commercial vehicle, what is the maximum legal blood alcohol concentration (BAC) allowed?

Accepted Answer

0.04%

Answer

For commercial vehicle drivers, the legal blood alcohol concentration (BAC) limit is significantly stricter than for non-commercial drivers. A BAC of 0.04% or higher is considered driving under the influence (DUI), reflecting the heightened responsibility and potential danger associated with operating large commercial vehicles.

Question 3

If your vehicle begins to skid, what should you do?

Accepted Answer

Turn the steering wheel in the direction of the skid

Answer

When a vehicle begins to skid, the correct action is to turn the steering wheel in the direction the rear of the vehicle is skidding. This technique, known as 'steering into the skid,' helps to realign the wheels with the direction of travel, allowing the tires to regain traction and the driver to regain control.

Question 4

How often should cargo be inspected during a trip?

Accepted Answer

Within the first 50 miles and every 150 miles thereafter

Answer

Federal regulations for commercial vehicles mandate frequent cargo inspections to prevent shifting loads, which can lead to instability and accidents. Cargo must be inspected within the first 50 miles of a trip and then every 150 miles or 3 hours thereafter (whichever comes first) to ensure it remains securely fastened.

Question 5

What is the purpose of air brakes in a commercial vehicle?

Accepted Answer

To provide additional braking power

Answer

Air brakes are essential in commercial vehicles due to their substantial size and weight, requiring significantly more stopping power than hydraulic systems. They utilize compressed air to apply force to the brake components, providing the robust and reliable braking capability necessary for safe operation of heavy vehicles.

(PennDOT) Pennsylvania Department of Transportation Practice Test

(PennDOT) Pennsylvania Department of Transportation Practice Test

PennDOT Commercial Driver's License