Who this is for: carrier, driver, owner-operator
The 7 BASICs of CSA Explained
The seven BASICs are the safety measurement categories at the heart of CSA. Each BASIC aggregates specific violation types from roadside inspections and crash reports. Understanding which violations feed into which BASIC helps carriers identify where their exposure lies.
BASIC 1: Unsafe Driving
Covers moving violations observed during roadside inspections and traffic enforcement. Examples: speeding, reckless driving, improper lane change, failure to use a seatbelt, texting while driving. This BASIC has a relatively low alert threshold because unsafe driving behavior is directly linked to crash risk.
BASIC 2: Hours of Service (HOS) Compliance
Covers violations of federal hours-of-service regulations under 49 CFR Part 395. Examples: exceeding the 11-hour driving limit, falsification of log records, missing or incomplete ELD data, failure to take required rest breaks. This BASIC triggers intervention at higher thresholds for most carriers.
BASIC 3: Driver Fitness
Covers violations indicating the driver is not properly qualified or licensed. Examples: operating with a suspended CDL, missing medical certificate, wrong CDL class for the vehicle operated, operating without required endorsements. This BASIC reflects regulatory qualification failures rather than behavioral driving issues.
BASIC 4: Controlled Substances and Alcohol
Covers drug and alcohol violations. Examples: operating under the influence of a controlled substance or alcohol, alcohol in the cab, refusing to submit to a drug or alcohol test. This BASIC has the lowest alert threshold — even a single qualifying violation may trigger intervention.
BASIC 5: Vehicle Maintenance
The most heavily populated BASIC. Covers vehicle mechanical violations found during inspections. Examples: brake defects, tire violations, lighting failures, cargo securement violations, coupling device defects. Because inspectors routinely check vehicle condition, this BASIC accumulates violations quickly for fleets with deferred maintenance.
BASIC 6: Hazardous Materials (HM) Compliance
Applies only to carriers transporting hazardous materials. Covers HM-specific violations: missing or incorrect placards, improper shipping papers, failure to comply with the Hazardous Materials Regulations. Non-HM carriers are not scored in this BASIC.
BASIC 7: Crash Indicator
Reflects the carrier's involvement in DOT-reportable crashes over the past 24 months. Unlike the other six BASICs, Crash Indicator data is not publicly visible in SMS — it is available to law enforcement and FMCSA investigators but not to the general public or shippers. The underlying crash reports remain in the system regardless of fault determination.
How violations are time-weighted within each BASIC
Within each BASIC, violations are weighted by both severity and recency. Severity weights run from 1 (minor) to 10 (critical), and are set by FMCSA for each specific violation type. Time weights amplify the impact of recent violations: a violation within the past 6 months counts more than one from 18–24 months ago. This means a clean inspection period after a bad stretch can meaningfully improve scores over 12–18 months even if the underlying old violations are still within the data window.
Violation severity — where the highest-impact items cluster
Not all violations contribute equally. FMCSA assigns severity weights on a 1–10 scale. Brake violations (out-of-adjustment brakes, brake lining defects) typically carry weights of 8. Operating with a suspended CDL or under the influence is a 10. ELD record falsification is a 10. Tire violations sit at 8. A single high-severity violation from a recent inspection contributes more to a small carrier's BASIC score than several low-severity violations from older inspections combined. When reviewing your SMS inspection detail, sort by severity weight to identify which items are doing the most damage, then address those first.
Frequently Asked Questions
Can I challenge a violation that feeds into my BASIC score?
Yes. Use the FMCSA DataQs system (dataqs.fmcsa.dot.gov) to dispute inspection violations or crash records you believe are inaccurate. Corrected records are reflected in SMS at the next monthly update after the state processes the correction.
Which BASIC is most commonly the cause of alert status?
Vehicle Maintenance is the most common, because it accumulates violations from routine inspections where defects are found. Unsafe Driving and HOS Compliance are also frequent sources of elevated scores.
Does the Crash Indicator BASIC affect shipper and broker decisions even though it's not publicly visible?
The Crash Indicator BASIC is not visible on the public SMS profile, so shippers and brokers cannot see the underlying data. However, FMCSA investigators can see it, and it factors into compliance review prioritization. Carriers with elevated Crash Indicator scores face higher scrutiny in enforcement — even if that exposure isn't visible commercially.
If a violation is in multiple BASICs, does it get counted twice?
Violations are assigned to specific BASICs based on their violation code — each violation type maps to one BASIC. A violation doesn't appear in multiple BASICs simultaneously. However, a single inspection event can produce multiple violations in different BASICs at the same time (for example, a brake defect in Vehicle Maintenance and an HOS violation in HOS Compliance from the same stop).