Overview
The Federal Hours of Service (HOS) regulations govern how long commercial motor vehicle (CMV) drivers may drive and work before mandatory rest periods. These rules apply differently to property-carrying and passenger-carrying drivers and are designed to prevent fatigue-related accidents. Mastering HOS rules is essential for both the CDL written exam and safe professional driving.
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Property-Carrying vs. Passenger-Carrying: At a Glance
| Rule | Property-Carrying | Passenger-Carrying |
|---|---|---|
| Max Drive Time | 11 hours | 10 hours |
| On-Duty Window | 14 hours | 15 hours |
| Required Off Duty | 10 consecutive hours | 8 consecutive hours |
| Restart | 34 consecutive hours off | 34 consecutive hours off |
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Drive Time Limits
Property-Carrying Drivers
• 11-Hour Driving Rule: A driver may drive a maximum of 11 hours after taking 10 consecutive hours off duty.
• 14-Hour Rule: Once a driver comes on duty, they have a 14-hour window in which driving is permitted. After 14 hours on duty, the driver may not drive again until completing 10 consecutive hours off — even if they haven't used all 11 driving hours.
- The 14-hour clock cannot be extended by taking breaks during the shift.
Passenger-Carrying Drivers
• 10-Hour Driving Rule: A driver may drive a maximum of 10 hours after taking 8 consecutive hours off duty.
• 15-Hour Rule: Passenger-carrying drivers may not drive after being on duty for 15 hours following 8 consecutive hours off duty.
> Key Distinction: The drive limit and the on-duty window are two separate clocks — a driver must comply with both simultaneously.
Key Terms
• Drive Time: Time spent actually operating the vehicle
• On-Duty Time: All time from when a driver begins work until relieved of all responsibility
• 14-Hour Window: The maximum on-duty period within which property drivers may drive
• 15-Hour Window: The equivalent limit for passenger-carrying drivers
⚠️ Watch Out For
• The 14-hour clock does not stop for breaks, meals, or fuel stops — time continues to count down.
• A driver who has only used 8 of their 11 driving hours still cannot drive once the 14-hour window expires.
• Do not confuse the 11-hour drive limit with the 14-hour on-duty window — they are not the same rule.
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Weekly/Cycle Limits
The Two Cycles
Drivers are subject to weekly limits based on which cycle their carrier uses:
• 60-Hour / 7-Day Rule: A driver may not drive after accumulating 60 on-duty hours in any 7 consecutive days.
- Used by carriers that do NOT operate every day of the week.
• 70-Hour / 8-Day Rule: A driver may not drive after accumulating 70 on-duty hours in any 8 consecutive days.
- Used by carriers that operate 7 days a week.
The 34-Hour Restart
• A driver may restart their 7- or 8-day clock by taking 34 or more consecutive hours off duty.
• After the restart, the driver begins a fresh 7- or 8-day cycle.
Key Terms
• On-Duty Hours: Total hours worked across the rolling 7- or 8-day period
• 34-Hour Restart: Off-duty period that resets the weekly cycle clock
• Rolling Window: The cycle counts the most recent 7 or 8 consecutive days, not a fixed calendar week
⚠️ Watch Out For
• The carrier's operating schedule — not the driver's preference — determines which cycle (60/7 or 70/8) is used.
• Reaching the weekly limit ends driving privileges even if daily drive and window limits haven't been reached.
• The restart provision is optional, not required — drivers may continue without restarting by waiting for older hours to "fall off" the rolling window.
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Rest & Break Requirements
30-Minute Break Rule (Property-Carrying)
• A driver must take a 30-minute break before driving if 8 cumulative hours have passed since the last off-duty or sleeper berth period of at least 30 minutes.
• The break may be taken as off duty or sleeper berth time — it does not have to be a driving interruption.
Required Off-Duty Time
• Property-carrying: Minimum 10 consecutive hours off duty before driving.
• Passenger-carrying: Minimum 8 consecutive hours off duty before driving.
Sleeper Berth Provisions
#### Property-Carrying Drivers (Split Sleeper Berth)
• Drivers may split required rest into two periods:
- One period of at least 8 consecutive hours in the sleeper berth
- One period of at least 2 hours (off duty or in sleeper berth)
- The two periods together must total 10 hours
• Time in the qualifying sleeper berth period does not count against the 14-hour window.
#### Passenger-Carrying Drivers (Split Sleeper Berth)
• Drivers may split the required 8 hours off duty into:
- At least 6 consecutive hours in the sleeper berth
- At least 2 hours off duty or in the sleeper berth
Key Terms
• Consecutive Hours: Hours that must be taken in an uninterrupted block
• Sleeper Berth: A built-in sleeping compartment in a CMV
• Split Sleeper Berth: Dividing the required off-duty period into two qualifying segments
• Cumulative Driving Time: Total driving hours added up since the last qualifying rest period
⚠️ Watch Out For
• "Consecutive" is the critical word — rest periods broken by any on-duty activity do not qualify.
• The sleeper berth split pauses the 14-hour clock for property drivers — this is a commonly tested concept.
• Passenger and property rules for sleeper berth splits are different — know both.
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Logbook & Record Keeping
The Four Duty Status Categories
Every driver must record one of four statuses at all times:
1. Off Duty (OFF) — Not working; personal time
2. Sleeper Berth (SB) — Resting in the vehicle's sleeper compartment
3. Driving (D) — Operating the CMV
4. On Duty, Not Driving (ON) — Working but not behind the wheel (loading, inspections, paperwork)
Required Log Contents
Each daily log page must include:
• Date
• Total miles driven
• Truck/tractor and trailer numbers
• Carrier name and main office address
• Driver's signature
• Graph grid showing duty status changes with remarks (city/state for each change)
• Time zone — ensures accuracy when crossing time zones
Log Retention Requirements
• A driver must carry the current day's log plus the previous 7 days of logs.
• This means 8 days total must be available for roadside inspection at all times.
Short-Haul Exemption
A driver is exempt from keeping a paper log if ALL of the following apply:
• Operates within a 150 air-mile radius of the normal work reporting location
• Returns to the same location within 14 hours
• Does not exceed 11 hours of driving
• The carrier maintains time records for at least 6 months
Key Terms
• Daily Log (RODS): Record of Duty Status — the official HOS document
• Graph Grid: Visual timeline showing duty status across a 24-hour period
• Short-Haul Exemption: Allows qualifying drivers to skip daily paper log requirements
• Air-Mile Radius: Straight-line distance (not road miles) used to calculate short-haul eligibility
⚠️ Watch Out For
• All four duty status categories must be used — "On Duty" and "Driving" are two separate statuses.
• Logs must reflect accurate times in local time zone — time zone recording is required, not optional.
• The short-haul exemption requires meeting all conditions simultaneously — failing even one disqualifies the driver.
• Pre-trip and post-trip inspections count as On Duty, Not Driving — not off duty.
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Special Rules & Exemptions
Adverse Driving Conditions Exemption
• Allows a driver who encounters unexpected hazardous conditions (snow, ice, fog, flooding) to drive up to 2 additional hours beyond the normal limit.
• This extends the driving window to reach a safe stopping point or complete a run.
• The conditions must be unexpected — conditions that were foreseeable before the trip began do not qualify.
• Applies to both property (up to 13 hours drive / 16-hour window) and passenger carriers.
Emergency Exemption
• A driver may exceed normal HOS limits when:
- A President, governor, or federal/state agency declares an official emergency
- The driver is providing relief assistance directly related to the declared emergency
• This exemption ends when the emergency declaration expires.
Personal Conveyance
• Definition: Use of a CMV for personal, non-work-related travel while off duty (e.g., driving to a restaurant, motel, or personal errand).
• Logged as: Off Duty time on the log.
• The vehicle must not be transporting cargo or acting in the carrier's interest during personal conveyance.
Oilfield Exemption
• Drivers transporting oilfield equipment or waiting at a well site may exclude waiting time from their on-duty calculation.
• Effectively pauses the HOS clock during well-site waiting periods.
• Applies only to drivers in qualifying oilfield operations.
Farming Exemption
• Drivers of vehicles used in farming operations during planting and harvest seasons may be exempt from federal HOS regulations.
• Specific exemption details vary by state and operation type.
Key Terms
• Adverse Driving Conditions: Unexpected weather or road hazards encountered en route
• Declared Emergency: Official government declaration triggering the emergency HOS exemption
• Personal Conveyance: Off-duty use of a CMV for personal travel
• Oilfield Exemption: Special HOS provision for drivers in well-site operations
⚠️ Watch Out For
• The adverse conditions exemption only applies to unexpected conditions — you cannot plan for bad weather and claim this exemption.
• Personal conveyance is off-duty time, but the driver must not be furthering the motor carrier's business.
• Emergency exemptions require an official declaration — personal judgment that conditions are dangerous is not enough.
• The oilfield exemption pauses the clock; it does not eliminate HOS rules entirely.
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Quick Review Checklist
Before your exam, confirm you can answer each of the following:
• [ ] State the 11-hour drive limit and 14-hour window for property-carrying drivers
• [ ] State the 10-hour drive limit and 15-hour window for passenger-carrying drivers
• [ ] Explain the difference between the 60/7 and 70/8 weekly cycles and which carriers use each
• [ ] Describe the 34-hour restart and when a driver would use it
• [ ] Explain the 30-minute break rule including when the break must be taken
• [ ] Describe the split sleeper berth rules for both property and passenger drivers
• [ ] List all four duty status categories and provide an example of each
• [ ] State how many days of logs (8 total) must be available during inspection
• [ ] List all three requirements for the short-haul exemption
• [ ] Describe the adverse conditions exemption and how much extra time it allows (2 hours)
• [ ] Define personal conveyance and explain how it is logged (off duty)
• [ ] Explain the oilfield exemption and its effect on on-duty time calculations
• [ ] Identify what information must appear on each page of a daily log
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Study Tip: Focus on the differences between property-carrying and passenger-carrying rules — exam questions frequently test whether you can distinguish between the two. Use comparison tables and mnemonics like "11-14-10 for property" and "10-15-8 for passengers" to keep the numbers straight.