Texas CDL General Knowledge Practice Exam

When are you required to use a logbook?

1. When driving any personal vehicle

2. When driving a commercial vehicle under 150 air miles

3. When driving a commercial vehicle and exceeding 150 air miles

4. When driving during night hours only

The correct answer is: When driving a commercial vehicle and exceeding 150 air miles

Using a logbook is a critical requirement for commercial drivers to ensure compliance with hours-of-service regulations. A logbook is mandated when a driver operates a commercial vehicle and exceeds 150 air miles from their starting point. This requirement is in place to monitor and manage driving hours to prevent fatigue-related accidents. When a driver operates a commercial vehicle within 150 air miles, they are typically considered to be local or short-haul, which allows for different regulations that do not necessitate the use of a logbook. This exception alleviates some of the administrative burdens for drivers who operate primarily in local ranges. The other options provided do not align with the regulations governing logbook usage. Personal vehicle operation does not require a logbook, and driving during night hours does not inherently trigger the need for one. Thus, the requirement for using a logbook is specifically tied to the distance traveled in a commercial vehicle, which is why the correct answer focuses on exceeding the 150 air miles threshold.