CSA BASIC Categories
The FMCSA Safety Measurement System (SMS) sorts every roadside-inspection violation into one of seven Behavior Analysis and Safety Improvement Categories — BASICs. Each BASIC produces a percentile score the FMCSA uses to prioritize carriers for interventions. Pick a BASIC below to see every violation code that feeds it, plus how each one is weighted.
BASIC
Unsafe Driving
Operating a CMV in a dangerous or careless manner
The Unsafe Driving BASIC captures dangerous CMV operation — speeding, reckless driving, improper lane changes, inattention, texting, and seat-belt violations. It is one of the most-cited BASICs at roadside inspections and a primary driver of CSA score impact for carriers.
See all Unsafe Driving codes →
BASIC
Hours-of-Service Compliance
HOS rules, ELD use, and driver log accuracy
The Hours-of-Service Compliance BASIC measures violations of driver duty-status, rest, and log requirements under 49 CFR Part 395. ELD non-compliance, false logs, and exceeding driving limits all fall here. This BASIC is heavily scrutinized in roadside inspections and federal audits.
See all Hours of Service codes →
BASIC
Vehicle Maintenance
Mechanical defects found at roadside inspections
The Vehicle Maintenance BASIC tracks mechanical defects identified at roadside inspections under 49 CFR Parts 393 and 396 — brakes, tires, lights, steering, coupling devices, and pre-trip inspection failures. This is one of the largest BASICs by volume of citations.
See all Vehicle Maintenance codes →
BASIC
Controlled Substances/Alcohol
Drug and alcohol regulation violations
The Controlled Substances/Alcohol BASIC captures drug- and alcohol-related citations — possession, use, refusal to test, and CDL holder violations of 49 CFR Part 382. This BASIC carries some of the highest individual severity weights and triggers immediate OOS for the driver.
See all Drugs & Alcohol codes →
BASIC
Hazardous Materials Compliance
HM placarding, paperwork, packaging, and route compliance
The Hazardous Materials Compliance BASIC covers placarding, shipping papers, package labeling, emergency-response info, and HM route restrictions under 49 CFR Parts 171–180. Carriers transporting hazardous materials face additional inspection scrutiny and CSA exposure.
See all HazMat codes →
BASIC
Driver Fitness
CDL, medical certification, and driver qualification
The Driver Fitness BASIC captures violations related to medical certification, CDL validity, endorsements, and driver qualification files under 49 CFR Parts 383 and 391. Driver Fitness violations often signal carrier qualification-file gaps.
See all Driver Fitness codes →
BASIC
Crash Indicator
Reportable crashes from the past 24 months
The Crash Indicator BASIC reflects state-reported crash involvement in the prior 24 months. Unlike other BASICs, individual violation codes are not tracked here — instead, crash records contribute based on severity, recency, and the carrier’s exposure.
See all Crash Indicator codes →
How BASIC scores actually work
Each violation in a BASIC gets a severity weight (1–10) plus a +2 OOS bonus when applicable. FMCSA time-weights these over a 24-month window — recent violations count 3×, then 2× up to 12 months, then 1× up to 24 months. The carrier’s total is normalized by exposure (vehicle inspections or driver inspections) and converted into a percentile against peers. Carriers above a BASIC’s threshold percentile become priorities for federal interventions.