Hours of service
Also called HOS
Hours of service are the federal limits on how long a commercial driver may drive and remain on duty before rest is required, designed to reduce fatigue-related crashes.
Last reviewed · by the Fleetchart team
The rules govern maximum driving time within a duty period, the total on-duty window, required rest breaks and weekly limits, with provisions for splitting rest in the sleeper berth.
Hours are effectively inventory. A load that consumes a full duty period for modest revenue has cost more than its fuel — it has cost the capacity to run something else.
Detention consumes this inventory without paying for it, which is why long dock waits are more expensive than the detention rate suggests.
For example, say a driver loses 4 hours waiting at a dock. At an average of 50 miles an hour, those are 4 × 50 = 200 miles the truck could have driven. If loads pay $2.50 a mile, the wait cost 200 × $2.50 = $500 in pay. If the rate con pays $50 an hour after 2 free hours, detention brings back only (4 − 2) × $50 = $100.
So plan loads by the hours they use, not just the miles. A short load that eats a whole day can pay less per hour than a longer one that loads and rolls.