What 393.60C means in plain language
FMCSR 393.60C covers the condition of every piece of glazing on your commercial motor vehicle — that means your windshield, side windows, and any other glass that affects what you can see while driving. The rule is triggered when any of that glazing is cracked, has become discolored over time, or is blocked by objects, stickers, or buildup to the point where your field of vision is meaningfully reduced.
The key phrase inspectors focus on is "reduced visibility." A hairline crack in the corner of a side window is not the same as a spider-web fracture running across the driver's line of sight, and a small dash-mounted GPS is not the same as a cluster of air fresheners and paperwork plastered across the lower windshield. Inspectors are making a judgment call about how much the obstruction or damage actually limits what you can see from the driver's seat.
In practical terms: anything mounted, hung, or stuck to the glass — and any damage to the glass itself — is fair game if an inspector decides it compromises your sight lines. That includes tinted films that have gone opaque, cracked defroster layers that scatter light, or sun shades left in place while driving.
What our enforcement data actually shows
Across our database of 13 million+ inspections, 393.60C has generated 67,056 all-time citations, placing it at #40 out of 3,036 FMCSR codes by citation volume. That's a high-frequency violation — the vast majority of FMCSR codes never come close to that count.
Enforcement is accelerating. Our inspection records show 43,796 citations in the last 12 months alone, and 9,737 citations in just the last 90 days. Looking at the monthly trend, volumes have been running between roughly 3,500 and 4,200 citations per month through early 2026, with 4,169 citations recorded in March 2026.
Here is where the data becomes genuinely reassuring for a driver who just got cited: the out-of-service rate for 393.60C is 0.0% across all-time records. Of 67,056 citations, only 31 resulted in an out-of-service order. You almost certainly drove away from that inspection. To put that in perspective, the all-FMCSR average OOS rate across all codes is 31.4%. This code sits essentially at zero. You received a citation and a CSA severity weight of 4, but you were not placed out of service, and the data shows that is the norm for this violation by an overwhelming margin.
The CSA severity weight of 4 does mean the citation will appear on your Safety Measurement System (SMS) record and factor into your carrier's BASIC scores. It is not a throwaway — but it is among the lower-severity weights in the system.
Who gets cited most
Looking at the last 180 days, Texas leads all states with 6,990 citations and a 0.0% OOS rate. The volume gap between Texas and every other state is dramatic. Coming in second is the federal inspection category (US) with 1,998 citations, followed by California with 1,685 citations and a 0.1% OOS rate. Arizona, New York, Washington, Florida, Alabama, Pennsylvania, and New Jersey round out the top ten, all with OOS rates at or near zero — the highest in the group being New Jersey at 0.3% across 353 citations, which is not meaningfully different from the others given the sample sizes.
In terms of carrier patterns, our data shows fleets such as AUTOTRANSPORTE CA-RI SA DE CV (USDOT 1759246) with 151 all-time citations and AKNA TRANSPORTES S DE RL DE CV (USDOT 1856796) with 129 all-time citations appearing near the top of citation counts. The concentration of cross-border carriers in the top-cited list aligns with the heavy Texas and border-region enforcement activity the data reflects.
How severe is this compared to similar codes
Compared to peer codes in the Vehicle Maintenance category, 393.60C looks very different in terms of OOS risk.
393.9(a) — Inoperable required lamps has 660,737 citations in our database and a 15.4% OOS rate. That means roughly 1 in 6 inspections for that code ends with the driver parked. 396.3(a)(1) — Inspection, repair, and maintenance (general) carries a 45.3% OOS rate across 236,919 citations — nearly half of those citations result in an OOS order. 393.78 — Windshield condition defective, the code most closely related to 393.60C, shows 157,894 citations and a 0.3% OOS rate, which is still three times higher than 393.60C's effective rate.
The pattern is clear: 393.60C is a high-volume, low-severity violation relative to its peers. You will see it on your record and your carrier will see it in their BASIC scores, but it does not carry the immediate operational consequence of the brake, lamp, or general maintenance codes that sit alongside it in the category.
How to avoid it
The co-occurring violation data from our inspection records gives a clear picture of what inspectors are finding alongside 393.60C. In the last 90 days, 1,296 inspections that included 393.60C also included 393.9 for inoperable required lamps, and 835 inspections paired it with 393.47E for defective slack adjusters. That tells you these citations are clustering on trucks that have deferred multiple maintenance items at once. Here is what you can do before and during every pre-trip:
- Walk the glass before you walk anything else. Stand outside each door and look at all glazing for cracks, chips, or discoloration that intersects your sight lines from the driver's seat. Check the windshield bottom edge where defroster strips often crack first.
- Clear the dash and windshield of anything mounted or hanging. GPS units, phone holders, and paperwork are all legal targets. Mount devices low and outside the primary sight arc.
- Check all required lamps during the same pass. Our data shows 1,296 co-occurring lamp citations in 90 days. If your lights are failing, inspectors are already looking at your glass.
- Confirm your periodic inspection documentation is on board. 393.60C co-occurred with 396.17C-PI (no proof of periodic inspection) in 1,010 inspections in the last 90 days. A missing PI form turns a minor citation into two.
- Pay extra attention if you operate a Freightliner or Kenworth. FRHT-branded vehicles account for 12,201 all-time citations under this code, and KW/Kenworth units together account for another 8,094. These platforms are not more dangerous — but they are more frequently inspected and cited, so their drivers need to be more diligent.
- Do not let cracks grow. A chip that could be repaired with a windshield kit today becomes a crack that crosses your sight line by next month's inspection cycle.