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Ready for some “exceptional” winter driving?

What is the adverse driving conditions exception and how can you use it?

Posted December 8, 2023

With winter driving conditions upon us, remember that there is an hours-of-service (HOS) exception available under some circumstances. Take some time now to remind your drivers and dispatchers about when and how the adverse driving conditions HOS exception applies.

What qualifies as adverse conditions?

In order to qualify for the adverse driving conditions exception, drivers must be confronted with dangerous weather conditions or unusual traffic conditions that were not known, or could not reasonably be known, to dispatchers and drivers immediately prior to beginning a run or continuing a run after a qualifying rest break.

Adverse driving conditions do not include rush-hour traffic, anticipated bad weather, or loading or unloading delays.

What does the exception allow?

Drivers of property-carrying commercial motor vehicles (CMVs) who encounter adverse driving conditions and cannot safely complete the run within the 11-hour driving limit or 14-hour duty window may increase their driving time and duty window by up to 2 hours to make up the time that was lost.

When using the exception, drivers of property-carrying vehicles may not drive:

  • For more than 13 hours following 10 consecutive hours off duty; or
  • At the end of the 16th consecutive hour since coming on duty following 10 consecutive hours off duty.

Drivers of passenger-carrying CMVs who encounter adverse driving conditions and cannot safely complete the run within the maximum 10-hour driving limit or 15 hours of on-duty time may increase their driving and on-duty time by 2 hours.

When using the exception, drivers of passenger-carrying vehicles may not drive:

  • For more than 12 hours following 8 consecutive hours off duty; or
  • After 17 hours of on-duty time following 8 consecutive hours off duty.

In Alaska, drivers of property-carrying or passenger-carrying CMVs who encounter adverse driving conditions may drive for the length of time needed to complete the run. After the run is completed, drivers of property-carrying CMVs must be off duty for at least 10 consecutive hours.

Drivers of passenger-carrying CMVs must be off duty for at least 8 consecutive hours. Drivers who use the exception should add notes to their logs to indicate when and why the exception was used.

This article was written by Lucero Truszkowski of J. J. Keller & Associates, Inc.

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