I start every state review the same way: I pull the raw counts before I look at any rate. Rates are useful, but they hide the denominator. Counts tell you where the work actually happened.
For Wyoming, the window covers 39 months, August 2023 through October 2026. In that span the state recorded 39,206 inspections and 77,806 violations, an average of 1.98 violations per inspection. Of those violations, 20,620 were out of service, for an out-of-service rate of 26.5%. The state's full month-by-month breakdown is on the Wyoming state page.
Nationally, over the same coverage period, the out-of-service rate is 17.6%, across 8,042,912 inspections and 12,865,241 violations. Wyoming's rate sits about nine points higher. That gap is the reason to look closer, but it is not a verdict on any one carrier.
What "out of service" actually means
Out-of-service is a status attached to a violation. When an inspector marks a violation out of service, the condition has to be corrected before the vehicle or driver can continue. That is why OOS counts matter more to a fleet than raw violation totals. A violation that gets written up but not marked OOS costs you a ticket. One marked OOS costs you a stopped truck, a reload, and a delivery window.
The status depends on the specific violation and the out-of-service criteria that apply to it, not on how the inspector feels about the truck. So when you read an OOS number, the useful question is which conditions drove it, not just how many there were.
Driver versus vehicle
The Wyoming figures split into driver and vehicle categories:
- Driver violations: 26,418, of which 6,208 were out of service.
- Vehicle violations: 50,524, of which 14,412 were out of service.
Vehicle violations make up most of the volume. That points to equipment on the truck as the main source of roadside trouble, rather than paperwork or driver status. Vehicle OOS is also where a fleet can act earliest. A proper pre-trip inspection catches many of the conditions an inspector will write, before the truck ever reaches a scale or a roadside pull-off. The catch is that a pre-trip only works if the driver is trained to look for the right things and the write-up gets acted on, not just signed.
The hazmat slice
Hazmat shows 621 violations, 193 of them out of service. That is a small number, and a small number moves a lot with a handful of inspections. I would treat it as a flag to watch, not a trend to plan around. The more useful question for a hazmat carrier is whether the OOS items cluster in one area, such as placarding, shipping paper handling, or equipment condition, because that tells you where your own process is weakest.
What the numbers do not tell you
A few cautions before anyone makes a decision on this:
- Violations are not trucks. One inspection can carry several violations, so the violation count overstates the number of vehicles that were stopped.
- Enforcement is not random. Where officers work, what they target, and which carriers they see all shape the rate. A high OOS rate can reflect a rough fleet population, a targeted enforcement effort, or both. The data alone does not separate those.
- The window is 39 months, not one year. Seasonal patterns and enforcement cycles can make a single year look different from the full run.
- These are inspection records. They describe conditions found at roadside. They do not directly measure crash risk, and I would not present them as if they did.
What I would do with this
If your trucks run through Wyoming, pull your own roadside history in the same format: total inspections, total violations, OOS counts, and the driver and vehicle split. Compare your vehicle OOS against your driver OOS separately. If your vehicle number is the problem, tighten pre-trip and post-inspection corrective action. If your driver number is the problem, look at how your drivers are trained to recognize and report conditions before they become write-ups.
The federal rules that these violations come from are in Title 49 of the Code of Federal Regulations, which you can read on eCFR. For the carrier-level picture, FMCSA publishes safety measurement data through the SMS website. Start with those sources, then compare them against your own records.
When I want to see how one state's pattern moves across a longer window, I use the map view and the broader insights pages to check whether a single month is an outlier or part of a trend.
Key takeaways
- Wyoming's OOS rate is 26.5% against a national 17.6% over the same coverage period.
- Vehicle violations (50,524) outnumber driver violations (26,418) by a wide margin.
- Hazmat counts are small (621 violations, 193 OOS), so treat them as a flag, not a trend.
- Violation counts do not equal truck counts, and enforcement emphasis shapes the rate.