The 14-Hour Rule
When a driver comes on duty after taking at least 10 consecutive hours off duty, he has a 14-hour window to complete his driving for the day. Although you cannot drive after the 14th hour, you can be on duty to perform other work-related duties. A violation can only occur while driving.
A simple way to approach the 14-hour rule:
Imagine a stopwatch. The time starts the second you come on-duty, after which you have 14 hours to complete your driving for the day. The stopwatch does not pause if you take a nap or lunch break, and to reset the 14 hour clock, you MUST take 10 hours off-duty. You can reset the 14 hour clock at any point so long as you take the minimum 10 hour break.
The 11-Hour Rule
A lot of people over complicate this rule, but it is actually rather simple, especially when you are using an electronic logbook, which is not the same as an ELD (see E-log vs. ELD). Within your 14-hour driving window, you are allowed to drive a MAXIMUM of 11 hours.
Let’s further simplify this with an example.
Frank comes on-duty at 4AM after a 10 hour break. He spends 2 hours loading cargo and begins driving at 6AM. He stops to take a 2 hour break from 11AM to 1PM. At this point, Frank has only spent 7 hours on-duty, but because the 14-hour rule takes into account both on-duty and off-duty time, Frank has actually lost a total of 9 hours from his 14-hour driving window. Frank decides he wants to cross through the rest of Arizona in one long run and estimates it will take him about 6.5 hours to complete the drive with an additional half-hour to unload. Can he legally do this?
NO. As you can see in the e-log above, Frank will have two violations if he tries to do this. His 14-hour window to complete his drive would end at 6PM since he came on-duty at 4AM. Driving past 6PM would violate the 14-hour rule. Additionally, at 7 PM, he would have been driving a total of 11 hours since his last 10-hour off duty period. Therefore, he would be in violation of both the 11 and 14-hour rules by continuing to drive after 7 PM.
Regardless, Frank would have to stop for a 10-hour break at 6PM before continuing his drive to avoid a violation.