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Guide

How CSA scores work, and what moves them

A CSA score is a percentile, not a grade. FMCSA's Safety Measurement System turns your roadside inspections, violations and crashes from the past 24 months into a measure in each of seven BASICs, then ranks you against carriers with a similar number of safety events on a 0-to-100 scale where higher is worse.

What CSA is, and what the SMS actually produces

CSA stands for Compliance, Safety, Accountability. It is FMCSA's safety compliance and enforcement program. The Safety Measurement System sits inside it. FMCSA describes the SMS as its "workload prioritization tool" — it exists to decide which carriers get a warning letter or an investigation. An intervention, in FMCSA's own definition, includes warning letters, roadside inspections and investigations.

The SMS reads three sources: roadside inspections, State-reported crash records, and acute and critical violations found during investigations. All of it lands in the Motor Carrier Management Information System. The SMS updates monthly.

A CSA percentile is not a safety rating. Safety ratings are Satisfactory, Conditional and Unsatisfactory, assigned from a compliance review against the safety fitness standard at 49 CFR 385.5. FMCSA says as much on the SMS site: the Alert symbol "is not intended to imply any federal safety rating of the carrier pursuant to 49 USC 31144." Replace with: "Brokers, shippers and insurers read whatever SMS data they can get, and they read it as a verdict. For a property carrier that is public measures, inspections and crashes — not percentiles, which came off public display under the FAST Act. How third parties use it is a commercial fact, not a regulatory one."

One scope note. FMCSA has approved a revised methodology that renames the BASICs "compliance categories" and replaces the 1-to-10 severity scale with a 1-or-2 scale. It is not in effect. FMCSA's guidance is explicit: "Until the updated system is in effect, carriers should continue to use the current SMS website to monitor their safety performance." Everything below describes the system in force.

The seven BASICs

The SMS organizes safety data into seven Behavior Analysis and Safety Improvement Categories. Each one is scored separately. There is no combined CSA number.

  • Unsafe Driving — operating a CMV in a dangerous or careless manner. Speeding, reckless driving, improper lane change, texting while driving, not wearing a safety belt.
  • Crash Indicator — the historical pattern of crash involvement, frequency and severity, built from State-reported crashes that meet the reportable standard. Not publicly available.
  • HOS Compliance — operating while ill or fatigued, and records-of-duty-status violations. Includes driving a property-carrying CMV more than 11 hours and failing to preserve RODS.
  • Vehicle Maintenance — failure to maintain the unit or secure the load. Inoperative brakes and lights, other mechanical defects, improper load securement, failure to make required repairs.
  • Controlled Substances/Alcohol — impaired operation, and failing to implement an alcohol and controlled substance testing program.
  • HM Compliance — unsafe handling of hazardous materials. Marking, labelling and placarding, package securement, leaking containers, missed cargo tank tests. Not publicly available.
  • Driver Fitness — drivers unfit through lack of training, experience or medical qualification. No valid CDL, medically unqualified, failing to maintain driver qualification files.
  • Insurance/Other Indicator — not a BASIC and not public. It carries registration, insurance and reporting violations found during investigations.

Why it is a ranking, not a score

The SMS first calculates a measure in each BASIC from your own data. The measure is absolute. Then it converts that measure to a percentile by comparing you to other carriers — and that is where most of the confusion starts.

Carriers are placed in safety event groups by how many safety events they have. In HOS Compliance the groups are 3–10 relevant driver inspections, 11–20, 21–100, 101–500 and 501 or more. Within each group, measures are ranked and converted to a percentile from 0 to 100. You are compared to carriers with a similar amount of exposure, not to the industry at large.

Unsafe Driving and Crash Indicator add a second cut. Carriers are segmented into Combination — combination trucks and motor coaches at 70% or more of power units — and Straight. Replace with: "The cut is on power-unit type, not on cargo. FMCSA counts truck tractors and motor coaches as Combination vehicles, and straight trucks, hazmat cargo tank trucks, buses, vans and limousines as Straight. A tractor-trailer fleet is not ranked against a straight-truck operation."

Normalization differs by BASIC, and this matters more than most carriers realize. HOS Compliance, Controlled Substances/Alcohol and Driver Fitness are normalized by driver inspections. Vehicle Maintenance and HM Compliance are normalized by vehicle inspections. Unsafe Driving and Crash Indicator are normalized by carrier size instead — average power units multiplied by a utilization factor built from VMT.

Add a sentence: "Controlled Substances/Alcohol has no inspection floor. A carrier is removed only if it has no violation in the BASIC at all, and the safety event groups are one, two, three, and four or more inspections with a violation — so a single violation can produce a percentile." Vehicle Maintenance, Driver Fitness and HM Compliance need at least five relevant inspections on the same terms. Unsafe Driving needs at least three inspections carrying an Unsafe Driving violation. Crash Indicator needs at least two applicable crashes.

The consequence: your percentile can move in a month in which nothing happened to you. Your measure stayed flat and your peer group shifted.

Severity weighting and time weighting

Every roadside violation that belongs to a BASIC carries a severity weight from 1 to 10 — 1 for the lowest crash risk, 10 for the highest. The weights are BASIC-specific. A 5 in one BASIC is not a 5 in another, and FMCSA warns that weights from different BASICs should not be added or equated.

Out-of-service conditions add 2 to the severity weight in most BASICs. Not in Unsafe Driving, where most violations are not OOS violations, and not in Controlled Substances/Alcohol, where most of them are. Severity weights for one inspection in one BASIC are capped at 30 in total, and that cap applies before time weighting.

Time weighting is the part worth internalizing. Each violation gets a time weight of 3, 2 or 1. Violations recorded in the past six months get 3. Over six months and up to twelve months, 2. Older than twelve months but inside twenty-four, 1. Nothing older than 24 months is used.

Work the arithmetic. Take two violations with the same severity weight in the same BASIC — say 6. Cited three weeks ago, it enters the measure at 6 × 3 = 18. Cited fourteen months ago, the same violation enters at 6 × 1 = 6. One fresh violation carries the weight of three identical ones from last year. That is why a quiet eighteen months does not protect you from a bad week.

Crashes work the same way on the clock. A reportable crash is one with at least one fatality, one injury where the person is taken for immediate medical attention, or one vehicle towed from the scene for disabling damage. Crash severity weights put more weight on injuries, fatalities and hazmat releases than on a tow-away.

Intervention thresholds and the Alert symbol

An intervention threshold is the percentile at or above which FMCSA flags the BASIC and may prioritize the carrier for interventions or further monitoring. Because higher percentiles are worse, a lower threshold is the stricter standard. FMCSA sets lower thresholds on the BASICs with the strongest association to crash risk, and lower thresholds for passenger and hazmat carriers because the consequences of their crashes are greater.

  • Unsafe Driving, Crash Indicator, HOS Compliance — 50% passenger carrier, 60% HM, 65% general.
  • Vehicle Maintenance, Controlled Substances/Alcohol, Driver Fitness — 65% passenger carrier, 75% HM, 80% general.
  • HM Compliance — 80% for all three carrier types.

What a percentile cannot tell you, and who can see it

The percentile is only half the trigger. A carrier also gets flagged in a BASIC if an investigation found one or more acute or critical violations in that BASIC in the past 12 months — regardless of percentile. Acute and critical regulations are defined in Appendix B to 49 CFR Part 385. Acute means noncompliance so severe that immediate corrective action is required. Critical means a breakdown in management or operational controls, and for it to affect BASIC prioritization status the violations must appear in at least 10% of the records checked with a pattern of more than one occurrence.

Public visibility is narrower than most people assume. The Crash Indicator and HM Compliance BASICs are hidden from public view entirely. Under the FAST Act of 2015, property carrier percentiles came off public display as well. What the public sees for a property carrier is inspection and crash data, investigation results, and measures for the public BASICs — and FMCSA notes those measures are "generated directly from safety data and not based on relative comparison to other motor carriers." All information on passenger carriers remains public. To see your own percentiles as a property carrier you log into the SMS with your U.S. DOT number and U.S. DOT PIN.

Drivers do not have CSA scores. The Driver Safety Measurement System is a tool for enforcement staff only — neither drivers nor their employing carriers can see it. PSP is a separate program holding three years of inspection reports and five years of crash reports, and it "does not provide a rating, score, or formal assessment of any kind." The carrier carries the record: inspections and crashes a driver picks up under your authority stay in your SMS data for two years unless overturned through DataQs, even if you terminate the driver.

The levers a carrier actually has

Five of them are real. Everything else is noise.

  • Clean inspections, in the right BASICs. For HOS Compliance, Vehicle Maintenance, Driver Fitness and Controlled Substances/Alcohol, the denominator is the total time weight of relevant inspections — including inspections that produced no violation in that BASIC. A clean Level 1 lowers the measure. For Unsafe Driving and Crash Indicator the denominator is average power units times a utilization factor, so clean inspections do not dilute those two.
  • Time, used deliberately. You cannot age a violation out early, but you know the schedule: weight 3 drops to 2 at six months, 2 to 1 at twelve, and the event leaves the window at twenty-four. Plan around the dates rather than discovering them.
  • Twelve clean months in a BASIC. In Unsafe Driving and Controlled Substances/Alcohol, carriers whose violations in the BASIC are all older than 12 months are eliminated from the percentile. In Crash Indicator, carriers with no crash recorded in the previous 12 months are removed. In HOS Compliance, Vehicle Maintenance, Driver Fitness and HM Compliance, a carrier is eliminated if it has no violation in the BASIC in the previous 12 months and no violation in the BASIC on the latest relevant inspection.
  • DataQs, for data that is wrong. DataQs lets you request and track a review of Federal and State data you believe is incomplete or incorrect. The adjudicated citation policy is the sharpest use of it: if the citation was dismissed or you were found not guilty, the violation is removed from the SMS; if you were convicted of a different charge, the severity weight is set to 1 and no OOS weight applies. You must submit certified documentation of the judicial proceeding through a Request for Data Review, and the policy applies only to inspections conducted on or after August 23, 2014.
  • Crash preventability. A crash found not preventable under FMCSA's Crash Preventability Determination Program is shown on the SMS site as "Reviewed – Not Preventable" and excluded from your Crash Indicator measure and percentile.

Where the work actually sits

None of this is difficult arithmetic. It is bookkeeping at volume. Knowing which inspections landed this month, which BASIC each violation hit, which violations are about to drop a time weight, which drivers and units keep appearing, and which records have a DataQ case worth filing. Delete it, or rewrite with no invented quantity: "Carriers without a dedicated safety person often learn about a score change from somebody else — an insurance renewal, a broker, or a warning letter."

Fleetmule syncs inspections and violations from FMCSA, shows what is driving a score change, and surfaces the records that may warrant a DataQ dispute. It connects to the ELD and TMS you already run rather than replacing them.

Common questions

What is a good CSA score?

There is no passing grade, because the number is a percentile rather than an absolute measure. What matters is whether a BASIC percentile sits at or above the intervention threshold for your carrier type. For a general carrier that is 65% in Unsafe Driving, Crash Indicator and HOS Compliance, and 80% in Vehicle Maintenance, Controlled Substances/Alcohol, Driver Fitness and HM Compliance.

How long do violations affect a CSA score?

Twenty-four months. Safety events older than 24 months are no longer used in the SMS. Inside that window the weight decays in steps: a time weight of 3 for the past six months, 2 for six to twelve months, and 1 for twelve to twenty-four months.

Can a clean inspection lower my CSA score?

FAQ: "In five BASICs, yes. HOS Compliance, Vehicle Maintenance, Driver Fitness, Controlled Substances/Alcohol and HM Compliance divide time- and severity-weighted violations by the total time weight of relevant inspections, including inspections with no violation in that BASIC, so a clean inspection lowers the measure. For HM Compliance only vehicle inspections where placardable quantities of HM are being transported count." Add HM Compliance to the body bullet the same way. Unsafe Driving and Crash Indicator are normalized by average power units and a utilization factor instead, so clean inspections do not dilute those.

Do drivers have CSA scores?

No. The Driver Safety Measurement System exists, but only enforcement staff can see it, and neither drivers nor their employing carriers have access. PSP is a separate program holding three years of inspection reports and five years of crash reports, and FMCSA states it does not provide a rating, score or formal assessment of any kind. Third-party driver scorecards are not FMCSA products and FMCSA does not validate them.

Why did my CSA score change when nothing happened this month?

Because the percentile is a rank inside a safety event group, not an absolute measure. The SMS updates monthly, your peers' data changes with it, and your own violations shift time weights as they cross the six- and twelve-month marks. Your measure can hold flat while your percentile moves.

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