CSA severity weights are numbers from 1 to 10 that the Federal Motor Carrier Safety Administration assigns to every roadside inspection violation, with 1 meaning the least crash risk and 10 meaning the highest.1Federal Motor Carrier Safety Administration. Safety Measurement System (SMS) Methodology The weight is the raw ingredient in your Safety Measurement System score: it gets multiplied by a time factor, capped per inspection, divided by your exposure, and then compared against other carriers to produce the percentile that decides whether FMCSA sends a warning letter or an investigator.
Where the 1-to-10 Numbers Come From
The severity scale is not in the Code of Federal Regulations. FMCSA built it into its SMS Methodology using crash correlation data and input from enforcement experts, and the full violation-by-violation list lives in the methodology’s Appendix A.2Federal Motor Carrier Safety Administration. SMS Methodology Appendix A – Violations List Violations that show up frequently at crash scenes sit at the top of the scale. Paperwork problems sit at the bottom.
The spread is wide. A general log form-and-manner violation under 49 CFR 395.8 is weighted at 1. Texting while driving, prohibited by 49 CFR 392.80, is weighted at 10.3eCFR. 49 CFR 392.80 – Prohibition Against Texting Once the time multiplier is layered on, a recent 10-point violation produces thirty times the weighted score of a stale 1-point violation, so the difference between a 4 and a 7 on the scale matters far more than it looks.
The Out-of-Service Bonus and the 30-Point Cap
Two adjustments hit the raw severity weight before anything else touches it.
When a violation is serious enough to place the driver or vehicle out of service, FMCSA adds 2 points to the base severity weight. A 6-point violation with an out-of-service order effectively becomes an 8. The bonus applies in most BASIC categories but not in Unsafe Driving or Controlled Substances/Alcohol, where the base weights are already high.4Federal Motor Carrier Safety Administration. Roadside Violation Severity Weights of the Safety Measurement System
Then comes the ceiling. Total severity weight from all violations found in one inspection, within a single BASIC, is capped at 30. The cap is applied before time multipliers, so a very bad inspection cannot spiral into hundreds of points. If the same violation code shows up more than once in the same inspection, it counts only once.1Federal Motor Carrier Safety Administration. Safety Measurement System (SMS) Methodology
Time Multipliers
Severity weights do not stay at full strength. FMCSA applies a time weight based on how recently the violation was recorded:
- 0 to 6 months old: time weight of 3.
- 6 to 12 months old: time weight of 2.
- 12 to 24 months old: time weight of 1.
A 10-point texting violation from last week generates 30 weighted points. A year later it drops to 20. After eighteen months it counts as 10. At the two-year mark it falls off the SMS record entirely.1Federal Motor Carrier Safety Administration. Safety Measurement System (SMS) Methodology
The same multipliers apply to the inspections themselves, on the exposure side of the equation. A clean inspection from last month is weighted at 3 in the denominator, which is why recent clean results move a percentile so effectively.
How the Weight Turns Into a Percentile
The full BASIC calculation runs in three layers.
Each violation’s severity weight is multiplied by its time weight. A 6-point brake violation from four months ago becomes 6 × 3 = 18 weighted points. Everything in the BASIC is summed.
That sum is divided by an exposure figure. For most BASICs, exposure is the total time weight of every relevant inspection over the past 24 months, including inspections that found nothing wrong. For Unsafe Driving and the Crash Indicator, exposure uses the carrier’s average power unit count. The result is a raw measure.
The raw measure is then compared against every other carrier in the same safety event group, which is set by how many relevant inspections or crashes the carrier has. The comparison produces a percentile from 0 to 100. Higher is worse.
Two practical consequences follow. Clean inspections dilute violation weight, so more inspections with the same number of violations produces a better score. And because the per-inspection cap is applied before the time multiplier, a single bad inspection is painful but survivable: 30 raw points multiplied by a time weight of 3 is 90, not the several hundred it could otherwise reach.
What the Weights Have to Reach Before FMCSA Acts
Weighted violations only matter once they push a BASIC percentile past its intervention threshold. Thresholds vary by category and carrier type:1Federal Motor Carrier Safety Administration. Safety Measurement System (SMS) Methodology
- Unsafe Driving, Crash Indicator, and Hours-of-Service Compliance: 65th percentile for general carriers, 60th for hazardous materials carriers, 50th for passenger carriers.
- Vehicle Maintenance, Controlled Substances/Alcohol, and Driver Fitness: 80th for general carriers, 75th for HM, 65th for passenger.
- Hazardous Materials Compliance: 80th for all carrier types.
Passenger and HM carriers face lower thresholds because the crashes involved tend to cause more severe outcomes. Crossing a threshold usually brings a warning letter first. If the BASICs are still over the line six months later, FMCSA can escalate to an investigation.5Federal Motor Carrier Safety Administration. Safety Measurement System Factsheet Carriers already designated high-risk, or those with three or more BASICs above threshold, skip the warning letter. Civil penalties for recordkeeping violations found during an investigation can reach $1,584 per day, up to $15,846.6Federal Register. Civil Penalties Schedule Update
Removing a Weighted Violation Through DataQs
If a violation was recorded in error, or the underlying citation was dismissed or reduced in court, you can challenge it through FMCSA’s DataQs system by submitting a Request for Data Review. Start at the FMCSA Portal and select DataQs from the available systems.7Federal Motor Carrier Safety Administration. DataQs
Inspection challenges must be filed within three years of the inspection. Crash challenges have five years.8Federal Register. Revisions to DataQs Requirements for MCSAP Grant Funding The state that ran the inspection handles the review. If denied, you have 30 days to ask for reconsideration and another 30 for a final review.
Certified court documentation showing a citation was dismissed or reduced is the strongest evidence.9Federal Motor Carrier Safety Administration (FMCSA). Correcting a Motor Carrier’s Safety Data (DataQs) Disagreeing with the inspector’s judgment rarely succeeds. Because a 10-point violation in its first six months generates 30 weighted points, removing even one high-severity violation can move a BASIC percentile noticeably.
Severity Weights Don’t Apply to Driver PSP Records
A driver’s Pre-Employment Screening Program record is a separate file. It shows the most recent five years of crash data and three years of inspection history, but it contains no percentile, no score, and no severity weighting.10Pre-Employment Screening Program. Frequently Asked Questions11Pre-Employment Screening Program. Are You a Driver? Employers see the raw violations and have to interpret them on their own. A violation drops off the carrier’s SMS profile at 24 months but stays on the driver’s PSP for three years, and crashes stay for five. Drivers can pull their own PSP record to check for errors before an employer sees it.
What to Do With the Numbers
The scoring is mechanical: it does not weigh context, intent, or the years of clean operation that came before a rough month. That works both ways. You can raise a percentile quickly with a cluster of high-weight recent violations, and you can lower one by fixing the underlying problems, running clean inspections to build the exposure denominator, and challenging any inspection that was recorded wrong. Prioritize the BASICs closest to their thresholds and the violations with the highest severity numbers, because those are the ones the formula is punishing hardest right now.