What is the minimum amount of time a driver must spend in a sleeper berth to be considered off duty?

To determine when a driver is considered off duty while using a sleeper berth, regulations stipulate a minimum duration for this to apply. Spending at least 2 hours in the sleeper berth qualifies the driver as officially off duty. This time allows for adequate rest and recuperation, which is essential for maintaining safety standards on the road.

The other durations mentioned are either below the required threshold or exceed the minimum without offering an added benefit related to the definition of off duty status. Therefore, the choice of 2 hours is aligned with safety regulations designed to ensure drivers have sufficient rest while still maintaining compliance with logging and hours of service rules.