Every driver has hit the point where the truck is fine, the load is ready and the clock says you’re done. Every new dispatcher learns this fast too, usually from an angry phone call. This guide explains the hours of service rules: the 11-, 14- and 70-hour limits, in plain numbers, with worked example days you can check against your own logs.
Everything here comes straight from the federal regulation, 49 CFR 395.3 on the eCFR. These are the property-carrying rules. If you haul freight, these are your limits.
Two Definitions That Control Everything
Before the limits make sense, you need to know what the regulation is counting. Under 49 CFR 395.2:
- On duty time is “all time from the time a driver begins to work or is required to be in readiness to work.” Pre-trips, loading, waiting at a dock and paperwork all count. Waiting counts unless the carrier has relieved you from duty.
- Driving time is “all time spent at the driving controls of a commercial motor vehicle in operation.”
All driving time is on duty time. A lot of on duty time is not driving time. Most HOS confusion comes from mixing up the two.
The Core Rules at a Glance
The 10-Hour Off-Duty Requirement
Under 49 CFR 395.3(a)(1), a driver may not drive without first taking 10 consecutive hours off duty. That reset gives you a fresh day.
The 14-Hour Rule
Under 49 CFR 395.3(a)(2), a driver may not drive after a period of 14 consecutive hours. That period starts “after coming on-duty following 10 consecutive hours off-duty.” The word that matters is consecutive. The 14-hour window runs straight through. Lunch, an ordinary nap in the truck or a long wait at the shipper does not pause it. The one exception is a qualifying sleeper berth split, covered below. When the window closes, driving is over until you get another 10 consecutive hours off.
The 14-hour rule limits driving after the window closes. It doesn’t stop you from doing other on duty work, but that work still counts toward your weekly total.
The 11-Hour Rule
Under 49 CFR 395.3(a)(3)(i), a driver may drive a total of 11 hours during that 14-hour period. Think of it as two limits running at once. You stop when you’ve driven 11 hours or when 14 hours have passed since you came on duty, whichever comes first.
The 30-Minute Break
Under 49 CFR 395.3(a)(3)(ii), driving is not permitted if more than 8 hours of driving time have passed without at least a consecutive 30-minute interruption in driving status. That interruption can be off-duty, sleeper berth or on-duty not driving time.
Two details trip people up. The break has to be 30 minutes in one block, so stops can’t be stacked up. It also doesn’t have to be off duty. Any 30 consecutive minutes out of driving status counts.
The 60-Hour and 70-Hour Rules
Which weekly limit applies depends on your carrier, not your preference:
- 60 hours / 7 days (49 CFR 395.3(b)(1)) applies if the employing motor carrier does not operate commercial motor vehicles every day of the week.
- 70 hours / 8 days (49 CFR 395.3(b)(2)) applies if the employing motor carrier operates commercial motor vehicles every day of the week.
These count on duty hours, not just driving. Every hour of loading, inspecting and waiting comes out of this total. The limit applies to “any period of 8 consecutive days” (or 7), so the window moves forward one day at a time. It isn’t a calendar week that resets on Sunday.
The 34-Hour Restart
Under 49 CFR 395.3(c), “Any period of 7 consecutive days may end with the beginning of an off-duty period of 34 or more consecutive hours.” The same applies to an 8-day period. Take 34 or more consecutive hours off and the weekly count starts over.
Worked Example Days
These examples use elapsed hours instead of clock times, so you can apply them to any start time. “Hour zero” is the moment the driver comes on duty after 10 consecutive hours off.
Example One: The Clean Day
- Hour zero: Driver comes on duty and does the pre-trip. The 14-hour window starts now.
- Driving block one: Driver rolls and drives 8 hours of driving time.
- The break: At the 8-hour driving mark, the driver must take a consecutive 30-minute interruption before driving again.
- Driving block two: Driver drives the remaining time, up to 11 hours of total driving.
- Shutdown: At 11 hours of driving, the wheels stop, even if there’s time left in the 14-hour window.
On a day like this, the 11-hour limit is what ends the day. That’s what a well-planned load looks like.
Example Two: The Detention Day
- Hour zero: Driver comes on duty at the shipper. The 14-hour window starts.
- Waiting: The load isn’t ready. Driver sits on duty for six hours.
- Driving: Driver finally rolls and drives 8 hours.
Now add it up: 6 hours waiting plus 8 hours driving is 14 hours. The window is closed. The driver has used only 8 of the 11 driving hours and is done driving for the day, with 3 driving hours unused. The 14-hour window ran the entire time they sat at the dock. (Any 30-minute break the driver took along the way would not change this, because the clock keeps running through it.)
Dispatchers, take note: a driver with “hours left” on the 11 can still be out of time on the 14. Check both numbers before you promise a delivery time.
Example Three: The Weekly Squeeze
A driver works for a carrier that runs trucks every day, so the 70-hour/8-day limit applies. The driver has stacked up long on duty days, and the total for the past 8 consecutive days is now at 70 hours.
- The driver still has a full 11 and 14 for today because they took 10 consecutive hours off.
- That doesn’t matter. Having been on duty 70 hours in any period of 8 consecutive days, the driver may not drive.
- There are two ways out. Wait for the 8-day window to move forward past the heavy days, or take a 34-hour restart so the 8-day period ends and the count starts over.
The daily clocks and the weekly clock run separately. You have to have time on all of them to drive.
Exceptions Worth Knowing
Sleeper Berth Split
Under 49 CFR 395.1(g)(1)(ii), drivers can split their required rest into two periods if:
- One rest period is at least 7 consecutive hours in the sleeper berth, which means a sleeper-equipped truck,
- Neither rest period is shorter than 2 consecutive hours,
- The two periods together total at least 10 hours, and
- The driving before and after each rest period, added together, does not exceed 11 hours and does not violate the 14-hour limit.
Here’s why it matters. Under 49 CFR 395.1(g)(1)(iii)(B), qualifying split rest periods are not counted when calculating the 14-hour window. For example, a 7-hour sleeper period paired with a separate three-hour break qualifies. Neither period counts against the 14. A driver who plans it correctly can use a qualifying split to pause the 14-hour clock. The 7-hour part has to be real sleeper berth time. On duty detention time does not qualify.
Adverse Driving Conditions
Under 49 CFR 395.1(b)(1), when adverse driving conditions hit, a driver may drive “for not more than two additional hours” beyond the limits in 395.3(a). The 2020 rule also extended by up to 2 hours the driving window in which this exception can be used.
Short-Haul Exception
Under 49 CFR 395.1(e)(1), the short-haul exception applies to drivers who operate within a 150 air-mile radius (172.6 statute miles) of the normal work reporting location and are released from work within 14 consecutive hours. Among the other requirements, the driver needs 10 consecutive hours off duty between 14-hour duty periods, and the employer must keep time records for 6 months. Drivers using this exception are exempt from the logging requirement in 395.8, the supporting documents requirement in 395.11 and the 30-minute break. Local and regional drivers should know whether their operation qualifies.
16-Hour Property-Carrying Exception
Under 49 CFR 395.1(o), a carrier can release a driver from duty within 16 hours after coming on duty following 10 consecutive hours off. When all the conditions in (o)(1) through (o)(3) are met, the driver is exempt from the 14-hour rule in 395.3(a)(2). Read those conditions on the eCFR before using it. It is not a general-purpose extension.
Where These Rules Came From
The current framework comes from the FMCSA final rule at 85 FR 33396-33452 (Docket FMCSA-2018-0248), published Monday, June 1, 2020, and effective September 29, 2020. That rule:
- Changed the 30-minute break trigger from 8 hours on duty to 8 hours of driving time,
- Extended the short-haul radius from 100 to 150 air-miles, and
- Extended by up to 2 hours the window for using the adverse driving exception.
If an older driver or trainer tells you the break kicks in after on duty time, that rule changed in 2020. The full text is in the Federal Register notice.
A Quick Checklist for Dispatchers
Before you assign or reroute a load, check every limit:
- 11: How much driving time is left today?
- 14: How much time is left in the window since the driver came on duty?
- 8 and 30: Is a 30-minute break due before the next stop?
- 70 or 60: How many on duty hours are left in the weekly window?
- Detention risk: Will waiting at the dock use up the 14 before the driver can roll?
Plan to the lowest of those numbers. A dispatcher who plans around the most restrictive clock keeps drivers legal and loads on time.
The hours of service rules aren’t complicated once you see them as separate clocks that all have to show time left before the truck moves. The 11 caps your driving, the 14 caps your day, the 30-minute break interrupts long stretches behind the wheel, and the 70 caps your week. Learn to read all of them at once and you’ll stop losing loads to surprises. Drivers who can do that are ready to move from the cab into dispatch and fleet management.
0 Comments