CDL · ELD & Hours-of-Service (HOS) Compliance · United States
ELD & Hours-of-Service (HOS) Compliance for the CDL Exam — U.S. candidates
6% of the CDL test plan. Electronic Logging Devices (ELDs) are required for most interstate CMV drivers; HOS rules cap driving and on-duty time to reduce fatigue-related crashes. Calibrated for American candidates.
Behind every published pass rate is a distribution of which topics caused most of the failures. This is one of those topics. ELD & Hours-of-Service (HOS) Compliance sits at roughly 6% of the Commercial Driver License content distribution — FMCSA mandates ELD use for nearly all interstate property- and passenger-carrying drivers. HOS rule violations (driving past the 11-hour limit, missing the 30-minute break, exceeding the 70-hour/8-day cycle) are top FMCSA roadside-inspection violations and a leading cause of out-of-service orders. In 2024, the published first attempt rate for CDL candidates in United States was 65% (FMCSA / state DMV aggregate (representative figure)). For U.S. candidates preparing for CDL, the calibration of study to local context matters: U.S. licensure exams are governed at the state level (CDL, NCLEX) or by national boards (MCAT, GRE). Pearson VUE and PSI are the dominant test-delivery vendors.
Common failure modes
These are the patterns that cause most candidates to lose marks on this topic. Recognising them in advance is half the work.
- !Confusing the 11-hour driving limit (consecutive driving cap) with the 14-hour on-duty limit (window after coming on duty)
- !Forgetting the 30-minute break required after 8 cumulative driving hours
- !Not using the sleeper-berth split correctly (8/2 or 7/3 split)
- !Failing to switch ELD duty status from on-duty to off-duty when stopping for personal time
Study tips
- 1Memorize the four core HOS limits: 11-hour driving, 14-hour on-duty window, 30-minute break after 8 hours of driving, 60/70-hour cycle limits.
- 2Practice the sleeper-berth split exception — 7/3 or 8/2 — until you can apply it without consulting a chart.
- 3Know the short-haul exemption (150 air-mile radius, 14-hour on-duty cap) — if you qualify, you may not need an ELD.
- 4Drill ELD duty-status codes: D (driving), ON (on-duty not driving), OFF (off-duty), SB (sleeper berth), and PC (personal conveyance).
- 5If you are testing in the U.S., expect CDL delivery via Pearson VUE or PSI test centres — register through the official board portal at least 30 days in advance.
Sample CDL ELD & Hours-of-Service (HOS) Compliance questions
These sample items mirror the format and difficulty of real CDL questions. Practice with thousands more on the free Koydo question bank.
- 1
A property-carrying driver has been driving for 8 hours straight. What is required before continuing?
- AStop for 10 hours off-duty
- BTake a 30-minute breakCorrect
- CSwitch to sleeper berth for 2 hours
- DNothing — they may continue to 11 hours
Why this answer?
HOS rules require a 30-minute break after 8 cumulative hours of driving. The break may be off-duty, sleeper-berth, or on-duty (not driving). Driving time may continue up to 11 hours after the break.
Frequently asked questions
Are paper logs ever still allowed?
What is the CDL ELD & Hours-of-Service (HOS) Compliance pass rate for American candidates?
How long should American candidates study ELD & Hours-of-Service (HOS) Compliance for the CDL?
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Related study guides
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- ELD & Hours-of-Service (HOS) Compliance for CDL — U.K. candidatesSame ELD & Hours-of-Service (HOS) Compliance topic, different locale framing
- ELD & Hours-of-Service (HOS) Compliance for CDL — Indian candidatesSame ELD & Hours-of-Service (HOS) Compliance topic, different locale framing
- ELD & Hours-of-Service (HOS) Compliance for CDL — Filipino candidatesSame ELD & Hours-of-Service (HOS) Compliance topic, different locale framing
Regulatory citation: 49 CFR Part 395 — Hours of Service of Drivers.