What 392.33(a) means in plain language
FMCSR 392.33(a) prohibits operating a commercial motor vehicle when the driver's view is obstructed to the front or sides. In practical terms: if something—whether it's dirt on windows, cargo blocking sight lines, damaged mirrors, or objects hanging from the cabin—prevents you from seeing the road ahead or to either side of your vehicle, you're in violation.
The regulation doesn't require perfect visibility in every direction; it's about maintaining sufficient sight lines to operate the vehicle safely. Obstruction can be caused by external conditions (mud, snow, ice buildup) or by how cargo is secured, hung, or positioned. Your job as the driver is to ensure your view remains clear before and during operation.
This is categorized as an Unsafe Driving violation, meaning the inspector determined your visibility impairment created a direct safety risk at the moment of inspection.
What our enforcement data actually shows
Across our 13 million+ inspection records, 392.33(a) is one of the least-cited violations in the FMCSR universe. All-time, we have recorded 29 citations for obstructed driver view, ranking this code #1816 out of 3,036 FMCSR codes by citation volume.
In the last 12 months, our database shows zero citations for this code. In the last 90 days, enforcement remained at zero. This extreme rarity reflects either excellent driver compliance or the fact that most inspectors catch and address visibility issues through other mechanisms before they escalate to a formal citation.
None of the 29 all-time citations resulted in an out-of-service (OOS) order. The OOS rate for 392.33(a) is 0.0%—meaning every citation issued was a warning or repair-on-the-spot situation, with no vehicle removed from service. For context, the all-FMCSR average OOS rate is 31.4%, so this code's enforcement is notably more lenient in outcome.
Who gets cited most
Our inspection records do not break down citations by state in the data provided. However, we can identify carriers with documented citations: William Riley (USDOT 3017087) accounts for 2 citations in our all-time records; the remaining carriers—including Triangle Electric Inc, Mandere Construction Inc, Heavy Duty Trucking Inc, and others—each have 1 citation.
The vehicle makes most frequently cited include International (4 citations), Kenworth (3 citations), and Freightliner (3 citations), followed by Sterling, Ford, Utility, and Chevrolet vehicles. This distribution suggests the violation is not concentrated in any single truck brand, but rather occurs across the full spectrum of commercial vehicle types.
How severe is this compared to similar codes
392.33(a) sits within the Unsafe Driving category alongside much higher-volume violations. For comparison:
392.2 (Operating a CMV while ill or fatigued) has recorded 1,208,164 all-time citations with a 0.8% OOS rate. This code is enforced at roughly 41,000 times the frequency of 392.33(a), reflecting that fatigue and illness are far more common enforcement targets.
392.2-SLLEQP (Operating a CMV while ill or fatigued, alternative classification) shows 72,352 citations with a 2.4% OOS rate, still orders of magnitude above obstructed view citations.
The stark difference in citation volume underscores that obstruction violations are outliers. When inspectors do cite them, they almost never result in OOS placement, indicating the violation is typically correctable on the spot—wipe the windshield, adjust the mirror, secure the load—rather than a fleet-wide or vehicle-wide defect.
How to avoid it
Before every trip:
- Clean all windows, mirrors, and reflective surfaces. Mud, salt, ice, and grime accumulate quickly and impair sight lines to the front and sides.
- Check that all mirrors are properly adjusted and securely mounted. A loose or damaged mirror creates blind spots.
- Verify that cargo, tarps, tie-downs, or hanging objects do not block your forward view or side visibility. Adjust or restow as needed.
- Inspect the windshield and side windows for cracks or damage that could obscure your view. A cracked windshield can be a secondary reason for a citation if visibility is already compromised.
- Ensure sun shades, interior decorations, or signage do not hang into your sight lines.
During operation:
- If weather causes window fogging or icing, pull over safely and clear your glass before continuing.
- Keep the cabin interior uncluttered so that nothing shifts into your line of sight during the drive.
- Do not hang objects from mirrors or the ceiling that could swing and obstruct your view.
- If you notice any deterioration in visibility—a cracked mirror, accumulated road spray—address it at the next safe stop or service location.
The enforcement data shows this violation is rare precisely because most drivers maintain clear sight lines as a matter of habit and safety instinct. Staying cited-free means making window and mirror clarity a routine pre-trip ritual.