The short haul 16 hour exemption. Has a few requirements to use it.
1. Can only be used if not used in the last 7 days or since last reset.
2. 8 and 11 hours clocks apply.
3. Must have started and ended last 5 work days at the same location.
4. (the actual exemption) Cannot drive after the 16th hour of coming on duty.
In a nutshell, it's an exemption to allow the daycabbers to get home if they, for example, have a blown tire.