The Adverse Driving Conditions (ADC) exception is part of the FMCSA Hours of Service (HOS) rules. It allows drivers to extend their driving time by up to 2 additional hours when facing unexpected hazards such as snow, ice, fog, heavy rain, high winds, or accidents.
This rule can only be used for unforeseen conditions - not for delays that were known or could have been predicted at the time of dispatch.
Drivers must stop once they reach a safe haven, such as a truck stop or rest area.
In the GPSTab app, only drivers can enable the Adverse Driving Conditions option.
You can activate it once per Shift or Sleeper Split Break (SSB), and only after your shift has already started.
When you tap the Adverse Driving button, a pop-up window will appear explaining the exception. You can also add an optional note before confirming.
After confirmation, the system automatically adds 2 extra hours to your Driving and Shift clocks, creates an “Adverse Driving Conditions” event, and marks ADC on your log graph.
Once activated, ADC cannot be turned off or applied again during the same shift.
If you try to enable it outside an active shift, you’ll see a message saying, “Adverse driving exception can be applied only during active Shift!”
Please check with the company before usage and use this feature only when truly needed - it helps you stay compliant while finding a safe place to stop during unexpected conditions.