FMCSA BASICs Explained: The 7 CSA Safety Categories

Disclosure: Informational only. We are not FMCSA or USDOT. Always verify your status directly through official FMCSA systems.

Think of the BASICs as seven separate report cards rather than one overall score. A carrier can look fine in Unsafe Driving and be flagged in Vehicle Maintenance. Knowing which violations land in which BASIC is how you work out where your safety data is exposed.

This guide explains each BASIC as its own category, shows how a violation travels from a roadside inspection to an intervention, and lists the thresholds FMCSA uses. If you want the basics of how percentiles are calculated, see how CSA scores work.

The 7 FMCSA BASICs at a Glance

Each BASIC maps to a set of regulations and a type of safety behavior. The table below summarizes all seven, based on FMCSA’s SMS overview and SMS Methodology version 3.21.

All seven can also pick up “acute” and “critical” violations found during FMCSA investigations, not just roadside inspections. Passenger and hazmat carriers face lower thresholds, covered below.

Each BASIC Explained

Each BASIC has its own definition, data source, way of adjusting for fleet size, and minimum amount of data needed before a percentile is shown. The details below come from FMCSA’s SMS Methodology and SMS overview.

1. Unsafe Driving BASIC

The Unsafe Driving BASIC covers operating a CMV in a dangerous or careless way. Typical violations include speeding, reckless driving, improper lane changes, texting, hand-held phone use, and failing to wear a seat belt.

• Regulations: 49 CFR Parts 392 and 397
• Adjusted by: average power units multiplied by a mileage-based utilization factor
• Percentile needs: at least 3 inspections with Unsafe Driving violations in 24 months

For the details, see our guides to common unsafe driving violations and speeding violations and CSA impact.

2. Crash Indicator BASIC

The Crash Indicator measures a carrier’s history of crash involvement, including how often and how severe. It is the only BASIC built from state-reported crash records rather than inspection violations. Crashes are weighted by severity, such as whether they involved an injury, a fatality, or a hazmat release.

• Adjusted by: average power units and utilization factor, like Unsafe Driving
• Percentile needs: at least 2 qualifying crashes
• Visibility: non-public; only the carrier (logged in) and enforcement can see it

3. Hours-of-Service (HOS) Compliance BASIC

The HOS Compliance BASIC covers driving while ill, fatigued, or out of compliance with hours-of-service rules. Violations include driving past the 11-hour or 14-hour limits, false records of duty status, and missing or incorrect ELD records.

• Regulations: 49 CFR Parts 392 and 395
• Adjusted by: number of relevant driver inspections
• Percentile needs: at least 3 relevant driver inspections

4. Vehicle Maintenance BASIC

The Vehicle Maintenance BASIC covers failing to maintain a CMV properly or to prevent shifting, spilled, or dropped cargo. Violations include brake, lighting, and tire defects, and cargo securement problems.

• Regulations: 49 CFR Parts 392, 393, and 396
• Adjusted by: number of relevant vehicle inspections
• Percentile needs: at least 5 relevant vehicle inspections

5. Controlled Substances/Alcohol BASIC

This BASIC covers operating a CMV while impaired by alcohol, illegal drugs, or misuse of prescription or over-the-counter medications. Having an alcoholic beverage in the cab also falls here.

• Regulations: 49 CFR Parts 382 and 392
• Adjusted by: number of relevant driver inspections
• Percentile needs: at least 1 inspection with a violation in this BASIC

6. Hazardous Materials (HM) Compliance BASIC

The HM Compliance BASIC covers unsafe handling of hazardous materials on a CMV. Violations include problems with packaging, marking, labeling, placarding, shipping papers, and load securement.

• Regulations: 49 CFR Part 397 and the Hazardous Materials Regulations, Parts 171 to 180
• Adjusted by: number of relevant HM inspections
• Percentile needs: at least 5 relevant HM inspections
• Visibility: non-public

7. Driver Fitness BASIC

The Driver Fitness BASIC covers drivers who are unfit to operate a CMV because of lack of training, experience, or medical qualification. Violations include driving without a valid CDL or the right endorsement, and without a valid medical certificate.

• Regulations: 49 CFR Parts 383 and 391
• Adjusted by: number of relevant driver inspections
• Percentile needs: at least 5 relevant driver inspections

The minimums above are the headline data sufficiency tests. The methodology adds further conditions in some BASICs, such as requiring a recent violation, so check the current methodology before relying on them.

How a Violation Becomes an Intervention

A violation affects a carrier only through the BASIC it lands in. SMS runs the same six-step chain for every BASIC each month, using the last 24 months of data.

1. Inspection or crash. A roadside inspector records violations on an inspection report, or a state reports a qualifying crash. Investigations can add acute and critical violations.
2. Sorted into a BASIC. Each violation code belongs to one BASIC. A speeding violation goes to Unsafe Driving; a brake defect goes to Vehicle Maintenance.
3. Weighted. Each violation’s severity weight (1 to 10) is multiplied by a time weight: 3 for the past 6 months, 2 for 6 to 12 months, 1 for 12 to 24 months. Severity weights from one inspection in one BASIC are capped at 30.
4. Normalized. Unsafe Driving and Crash Indicator are divided by average power units adjusted for miles driven. The other five are divided by the number of relevant inspections, so a carrier is not penalized just for being inspected often.
5. Ranked against peers. The result is compared with carriers that have a similar number of inspections or crashes (a “safety event group”) to produce a percentile. Higher is worse.
6. Intervention. If a percentile is at or above the BASIC’s threshold, FMCSA may intervene. Early contact includes a warning letter or a targeted roadside inspection. More serious cases lead to an offsite, onsite focused, or onsite comprehensive investigation, and possibly a notice of violation or notice of claim.

The mechanics of step 5 are covered in our guide to the FMCSA Safety Measurement System.

BASIC Intervention Thresholds by Carrier Type

Each BASIC has its own intervention threshold, and the threshold is lower for passenger and hazmat carriers. The lowest thresholds apply to the three BASICs FMCSA treats as most closely linked to crash risk: Unsafe Driving, Crash Indicator, and HOS Compliance.

Source: SMS Methodology, version 3.21 (June 2026).

A percentile at or above the threshold marks that BASIC for possible intervention. It does not by itself mean a carrier is unsafe, and it does not change the carrier’s safety rating. If you run passengers or hazmat, you hit the threshold sooner.

What BASICs Are Not

BASIC percentiles are a prioritization tool. They are not a safety rating, and they are not a legal finding that a carrier is unsafe. Three distinctions matter.

BASICs are not your safety rating. A Satisfactory, Conditional, or Unsatisfactory safety rating comes from an FMCSA compliance investigation under 49 CFR Part 385. SMS percentiles help FMCSA decide whom to investigate. They do not change a rating on their own.

Not every BASIC is public. The Crash Indicator and HM Compliance BASICs are non-public for all carriers. Under the Fixing America’s Surface Transportation (FAST) Act of 2015, property carriers’ SMS results are also no longer shown on the public SMS website (SMS Methodology). Carriers can still see their own results by logging in, and enforcement can see everything.

No percentile is not the same as a clean record. A carrier below a BASIC’s data sufficiency minimum gets no percentile, but its inspections and violations are still recorded. Those violations still appear in its inspection history and in drivers’ PSP records.

If a violation on your record is wrong, you can challenge it through FMCSA’s DataQs system. A corrected or removed violation drops out of the BASIC calculation.

How the BASICs Are Changing

FMCSA has approved a revised SMS methodology that replaces the seven BASICs with seven “compliance categories.” The biggest changes are to Controlled Substances/Alcohol, which merges into Unsafe Driving, and Vehicle Maintenance, which splits in two. We did not find an official go-live date in FMCSA’s published materials as of September 2026, and the current methodology (version 3.21, June 2026) still uses the BASICs.

Other approved changes, according to FMCSA’s summary of approved changes:

• Simpler severity weights. Violations are regrouped into about 100 violation groups, and the 1 to 10 severity scale becomes weights of 1 or 2.
• Proportionate percentiles. Safety event groups are replaced by percentiles based on each carrier’s exact number of safety events.
• New thresholds for some categories. The HM threshold rises from 80% to 90%. Driver Fitness rises to 90% for general carriers, 85% for hazmat, and 75% for passenger carriers.
• Stricter data sufficiency. A recent-violation requirement is extended to Hours of Service, Vehicle Maintenance, Hazardous Materials, and Driver Fitness.

The underlying logic stays the same: violations roll up into categories, categories produce percentiles, and percentiles drive interventions. Watch the CSA website for FMCSA’s announcement of the switch.

Know Where Your BASICs Stand

Each BASIC traces back to a specific compliance program: driver qualification files for Driver Fitness, logs and ELDs for HOS, inspections and repairs for Vehicle Maintenance, testing for Controlled Substances/Alcohol.

SafeRoad Compliance helps owner-operators and small fleets set up those programs, review their SMS data by BASIC, and file DataQs challenges when records are wrong. If you want a BASIC-by-BASIC review of your carrier’s data, contact SafeRoad Compliance.

FMCSA BASICs FAQ