What 172.203D6 means in plain language
172.203D6 is a hazardous materials labeling requirement under the Department of Transportation's hazmat regulations. This code specifically addresses how you must label packages, containers, or other forms of packaging that contain regulated hazardous materials. The regulation requires proper identification and marking of hazmat contents using prescribed label formats and placement rules.
If you've been cited for this violation, it means a roadside inspector determined that a hazardous material shipment in your vehicle did not comply with the specific labeling standard covered by this code. The violation can include missing labels, improperly positioned labels, labels that don't meet size or format specifications, or labels applied to the wrong type of container.
What our enforcement data actually shows
Across our 13 million+ inspection records, 172.203D6 has generated only 7 all-time citations, with 4 in the last 12 months and 2 in the last 90 days. This makes it one of the least-cited FMCSR codes—ranked 2312 out of 3,036 by citation volume.
Most importantly for your situation: this code has a 0.0% out-of-service rate across all citations in our database. Not a single driver or vehicle has been placed out of service for this violation. This is dramatically lower than the all-FMCSR average of 31.4%, meaning inspectors treat this violation as a documentation or administrative issue rather than an immediate safety threat that warrants removing you from the road.
The rarity of enforcement and the zero OOS rate suggest this violation is either caught infrequently or is typically resolved with a written citation rather than roadside enforcement action.
Who gets cited most
Our data shows citations for this code are concentrated in Texas, which accounts for 3 citations in the last 180 days—all with a 0.0% out-of-service rate. This is the only state in our top-states list for 172.203D6, indicating enforcement is extremely localized.
Looking at carriers in our database, American Piping Inspection Inc (USDOT 1987749) appears most frequently with 3 all-time citations for this code. Other carriers cited include Greenwood Motor Lines Inc, Alpha Testing LLC, Crest Pumping Technologies LLC, and Precision NDT LLC, each with 1 citation. We note these citations without implying any pattern of negligence—hazmat labeling violations can occur across any fleet handling regulated materials.
How severe is this compared to similar codes
172.203D6 sits in the hazardous materials category alongside several higher-enforcement codes. For context, 177.834A-HMC (general loading/unloading hazmat violations) has 3,954 citations with a 99.2% out-of-service rate—meaning that code almost always results in roadside enforcement action. Similarly, 177.817(a) (placarding violations) has 2,274 citations with a 75.1% OOS rate.
By contrast, 172.516(c)(6) (placard damaged, deteriorated, or obscured) has 1,796 citations but only a 1.6% OOS rate, and 172.602(c)(1) (emergency response information maintenance) has 1,464 citations with 0.0% OOS rate—similar to your code. This suggests that labeling and documentation violations in the hazmat space are treated more leniently than active loading, unloading, or general hazmat handling violations.
How to avoid it
Based on co-occurring violations in our inspection data, the following actions will reduce your risk:
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Verify hazmat label placement and orientation before loading. Our data shows 172.203D6 frequently co-occurs with 172.403G (improper RAM labeling), 172.403B, and 172.403F (label positioning violations). Spend 30 seconds pre-trip checking that all hazmat labels are properly affixed, facing outward, and positioned exactly as your manifest requires.
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Cross-check labels against your bill of lading and the DOT hazmat list. Two co-occurring violations (172.203D5 and 172.203D4) suggest label-to-shipment mismatches are common. Confirm the hazard class, label type, and packaging category on your paperwork match the physical labels on the vehicle before you leave the facility.
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Inspect label condition during vehicle inspection. If a label is torn, faded, or partially obscured (common triggers for related codes like 172.516(c)(6)), replace it. Labels must remain legible and visible throughout transport.
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If hauling multiple hazmat classes, ensure each is labeled separately. The co-occurrence of 172.406E (duplicate label requirement) in our data indicates confusion around multi-class shipments. Use the label format and placement prescribed for each hazard class.
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Request pre-trip verification from your dispatcher or safety team. Given the administrative nature of this violation, a quick second set of eyes on your hazmat labeling before departure can catch errors before an inspector does.
Vehicle makes cited most often (Ford appearing in 3 of 7 citations) do not indicate a pattern—the sample is too small. Focus on your own pre-trip process rather than vehicle type.