A single out-of-service percentage sounds like a verdict on a state. It isn't one until you know what the percentage counts. I pulled the Delaware roadside record for August 2023 through October 2026, 39 months of data, and compared it against the national totals for the same field definitions. The headline is real. The interpretation takes more care.
Start with the state profile on the Delaware insights page, then come back here for the arithmetic.
What the record contains
Delaware shows 23,721 inspections and 23,697 recorded violations over the period. Nationally the same window shows 8,023,075 inspections and 12,832,668 violations. Out-of-service (OOS) violations in Delaware total 7,143.
The state's oosRate is 30.1. That figure is 7,143 divided by 23,697, which is OOS violations divided by all violations. The national equivalent is 2,265,247 divided by 12,832,668, or 17.7. On that basis Delaware is about 1.7 times the national rate.
Same data, different denominator
Divide by inspections instead and the picture shifts. Delaware's 7,143 OOS violations over 23,721 inspections is again about 30.1. Nationally, 2,265,247 over 8,023,075 is about 28.2.
So the gap that looks large per violation is only about two points per inspection. Those two rates answer different questions:
- Per violation asks: when an inspector writes something down, how often is it an out-of-service item?
- Per inspection asks: how often does a stop end with an out-of-service item at all?
Delaware averages roughly one violation per inspection, against about 1.6 nationally. Fewer citations per stop, but a larger share of them tagged out-of-service. The data does not say why. It could reflect enforcement emphasis, the mix of carriers that run through the state, or how inspectors in that jurisdiction code findings. I would not tell a dispatcher that Delaware is "harder" on the strength of this table alone.
Where the driver-side gap sits
The sharpest difference in the file is on the driver side. Delaware recorded 3,745 driver violations, of which 1,557 were out-of-service. That is 41.6 percent. Nationally, 563,982 of 2,345,126 driver violations were OOS, or 24.0 percent.
That gap is worth more attention than the headline number, because it points at something a carrier can actually influence through training and pre-trip discipline rather than through route choice.
Two things I will not claim
Vehicle-side numbers do not reconcile. Delaware shows 5,586 vehicle OOS violations against 3,869 vehicle violations. An out-of-service count cannot exceed the total it belongs to, so one of these fields is either defined differently or drawn from a different pull. The category totals also fall short of the overall count: driver, vehicle, and hazardous materials violations add to 7,618, while the total is 23,697. Until the breakdown is verified against the source, I am not drawing any conclusion about Delaware's vehicle side.
Hazmat is too small to read. Delaware logged 4 hazardous materials violations and no OOS hazmat findings. Nationally the field shows 56,463 violations and 14,992 OOS, about 26.6 percent. Four events cannot support a rate.
What to do with this
If you run in Delaware, the useful work is internal. Pull your own inspection history and split it the same two ways: per violation and per inspection. Then look at the driver-side items separately from vehicle-side items, and check whether your drivers are being cited on the same categories that drive the state's driver OOS share.
The state-level numbers tell you where to look. The violation codes behind each out-of-service call tell you what to fix. Those codes are on the record for each inspection, and they are what separate a sloppy pre-trip from a real defect.
Key takeaways
- Delaware's 30.1 percent OOS rate is per violation, not per inspection. Per inspection, it is close to the national 28.2 percent.
- Delaware writes about one violation per inspection versus about 1.6 nationally, but more of those violations are out-of-service.
- The clearest gap is on the driver side: 41.6 percent OOS versus 24.0 percent nationally.
- Vehicle-side and hazmat figures in this pull need verification before anyone draws conclusions from them.
- Always check the denominator before you repeat a state-level OOS percentage.
For the full state-by-state view and the map, see the map and the broader insights index.