Commercial Driving General Knowledge 2

Question 1

What is the 14-hour rule in Hours of Service regulations?

Accepted Answer

You cannot drive beyond the 14th consecutive hour after coming on duty, following 10 hours off

Answer

The 14-hour rule limits the window in which driving can occur. Once you start your duty day, you have 14 hours before driving is no longer permitted, regardless of breaks taken.

Question 2

What is the required minimum tread depth for front tires on a commercial vehicle?

Accepted Answer

4/32 of an inch

Answer

Federal regulations require front tires on commercial vehicles to have at least 4/32-inch tread depth. Other tires require at least 2/32 inch.

Question 3

What is the purpose of a Driver Vehicle Inspection Report (DVIR)?

Accepted Answer

To document vehicle condition at the end of each driving day and report any defects

Answer

The DVIR is a written report documenting the condition of the vehicle and any defects found. It must be completed at the end of each driving day.

Question 4

What blood alcohol concentration (BAC) is the legal limit for commercial drivers?

Accepted Answer

0.04%

Answer

Commercial drivers are held to a stricter BAC standard of 0.04%, which is half the legal limit for non-commercial drivers (0.08%).

Question 5

What is the 60/70-hour rule?

Accepted Answer

You cannot drive after accumulating 60 hours in 7 days or 70 hours in 8 days on duty

Answer

The 60/70-hour rule limits total on-duty time. Drivers for carriers not operating every day are limited to 60 hours in 7 days; those operating every day are limited to 70 hours in 8 days.

Commercial Driving Practice Test

Commercial Driving Practice Test

Commercial Driving General Knowledge 2