7 CSA BASIC Categories Explained: Complete Breakdown
FMCSA's CSA program evaluates every motor carrier across seven Behavior Analysis and Safety Improvement Categories (BASICs). Each BASIC tracks a specific type of safety behavior, and each has its own set of violations, severity weights, and intervention thresholds. This guide breaks down every category so you know exactly what is being measured, what counts against you, and what triggers FMCSA action.
7 BASICs
Safety Categories
1-10
Severity Weight Scale
65% / 80%
Intervention Thresholds
24 Months
Rolling Data Window
O Trucking Editorial Team
Trucking Industry Experts
Fact-Checked by O Trucking Compliance Team
5+ years helping carriers understand and manage their CSA BASIC profiles
This article was written by the O Trucking editorial team with 9+ years of combined trucking industry experience. Learn more about us.
O Trucking7 CSA BASIC Categories Explained: Complete Breakdown
Before diving into each BASIC, understand that FMCSA calculates your percentile ranking in each category by comparing your violation data against carriers with a similar number of inspections (your "safety event group"). Each violation is assigned a severity weight from 1 (minor) to 10 (critical), then multiplied by a time weight based on how recent the violation is. The resulting score determines your percentile ranking. For step-by-step instructions on viewing your scores, see our how to check your CSA score guide.
1. Unsafe Driving
Intervention Threshold: 65% (General) | 50% (HazMat/Passenger)
This BASIC tracks driving behavior violations observed during roadside inspections or reported through traffic enforcement. It measures how safely drivers operate commercial motor vehicles on the road. This is one of the most closely watched BASICs by both FMCSA and freight brokers because it directly correlates with crash risk.
Common Violations:
- Speeding (highest severity weight at 15+ mph over)
- Reckless driving / improper lane changes
- Following too closely
- Texting or using a handheld mobile device while driving
- Failure to obey traffic signals or signs
- Seatbelt violations
Business Impact:
Elevated Unsafe Driving scores are the number one reason brokers reject carriers during vetting. A carrier with a 70%+ Unsafe Driving BASIC will be blocked from load boards at most major brokerages. Insurance underwriters weight this BASIC heavily in premium calculations because it is the strongest predictor of future crashes.
2. Hours of Service Compliance
Intervention Threshold: 65% (General) | 50% (HazMat/Passenger)
This BASIC measures compliance with hours of service regulations and ELD requirements. It captures violations related to driving time limits, required rest periods, record of duty status errors, and ELD device compliance. For the full penalty breakdown, see our ELD violations and fines guide.
Common Violations:
- Exceeding 11-hour driving limit
- Exceeding 14-hour on-duty window
- Exceeding 60/70-hour weekly limit
- No ELD installed or operating with unregistered device
- Record of duty status (RODS) form and manner errors
- 30-minute break violations
Business Impact:
HOS violations tell brokers that your drivers are operating fatigued, which is a major safety and liability concern. These violations also frequently result in out-of-service orders that park your truck for 10+ hours, costing revenue and disrupting delivery schedules. The HOS BASIC is the second most scrutinized category by carrier vetting platforms.
3. Driver Fitness
Intervention Threshold: 65% (General) | 50% (HazMat/Passenger)
Driver Fitness tracks whether drivers are properly licensed, medically qualified, and meet all federal requirements to operate a commercial motor vehicle. Violations in this BASIC often stem from administrative oversights rather than dangerous driving behavior, but they still carry significant CSA weight.
Common Violations:
- Expired or invalid CDL
- Expired DOT medical certificate (medical card)
- Operating without proper endorsements (HazMat, doubles/triples, tanker)
- Incomplete driver qualification file
- Non-English speaking driver without waiver (when required)
Business Impact:
Driver Fitness violations are highly preventable with proper record-keeping. An expired medical card, for example, is a simple calendar tracking issue. Carriers who track expiration dates for CDLs, medical certificates, and endorsements avoid this BASIC entirely. Operating with an unqualified driver can also trigger immediate out-of-service orders for the driver and potential DOT investigation of the carrier.
4. Controlled Substances / Alcohol
Intervention Threshold: 65% (General) | 50% (HazMat/Passenger)
This BASIC tracks violations related to drug and alcohol use by commercial drivers. It carries some of the highest severity weights in the entire CSA system because impaired driving poses an extreme risk to public safety. Even a single violation in this category can devastate a carrier's CSA profile.
Common Violations:
- Operating under the influence of drugs or alcohol
- Positive drug or alcohol test result
- Refusal to submit to required testing
- Possession of controlled substances in cab
- Alcohol within 4 hours of duty (BAC 0.04+ is a violation)
Business Impact:
A single controlled substance or alcohol violation has a severity weight of 10 (the maximum) and can push this BASIC above the intervention threshold by itself. It also results in immediate driver disqualification and can trigger an FMCSA investigation of the carrier's drug and alcohol testing program. Insurance carriers may non-renew policies upon learning of a substance violation.
Zero Tolerance for This BASIC
5. Vehicle Maintenance
Intervention Threshold: 80% (All Carriers)
Vehicle Maintenance tracks mechanical condition violations found during roadside inspections. This is often the most populated BASIC because Level I inspections include a thorough vehicle examination that can generate multiple maintenance violations in a single stop. The intervention threshold is higher (80%) because of the volume of data in this category.
Common Violations (Most Frequent First):
- Brake adjustment / brake system defects (most common overall)
- Lighting violations (inoperable lights, missing reflectors)
- Tire defects (tread depth, flat, damaged)
- Windshield / window defects
- Exhaust system leaks
- Frame / body / coupling device defects
Business Impact:
Vehicle Maintenance violations with high severity weights (brakes, tires) can result in out-of-service orders that park your truck until repairs are made. Brake violations are the most common cause of vehicle OOS orders. This BASIC is the easiest to improve through consistent pre-trip inspections and preventive maintenance programs. See our CSA improvement guide for specific strategies.
6. HazMat Compliance
Intervention Threshold: 80% (All Carriers)
HazMat Compliance measures adherence to regulations governing the safe transportation of hazardous materials. This BASIC only applies to carriers that transport hazardous materials, but violations carry extremely high severity weights because of the public safety implications. Even carriers who haul HazMat infrequently need to ensure full compliance on every HazMat shipment.
Common Violations:
- Improper or missing placarding
- Incomplete or inaccurate shipping papers
- Expired HazMat endorsement on CDL
- Improper packaging or container failures
- No safety data sheets or emergency response guide
Business Impact:
HazMat violations carry some of the steepest fines in the FMCSA penalty schedule, with single violations potentially reaching $80,000+ in extreme cases. Even with the higher 80% intervention threshold, a single improperly documented HazMat shipment can generate enough high-severity violations in one inspection to push a small carrier above the threshold.
7. Crash Indicator
Intervention Threshold: 65% (General) | 50% (HazMat/Passenger)
The Crash Indicator BASIC is unique because it is based on crash involvement data rather than violation data from inspections. It measures the frequency and severity of DOT-reportable crashes involving a carrier's vehicles. FMCSA uses state-reported crash data and weighs crashes based on severity (fatal, injury, tow-away).
What Counts:
- Fatal crashes (highest severity weight)
- Injury crashes
- Tow-away crashes (vehicle towed from scene due to disabling damage)
Business Impact:
The Crash Indicator is particularly impactful for small carriers because one or two crashes can push the percentile above the threshold. Unlike other BASICs, you cannot "dilute" crash data with clean inspections. However, if a crash was not your fault, you can challenge the crash accountability determination through the DataQs system to have it removed from your CSA record. Note that FMCSA currently counts all DOT-reportable crashes regardless of fault determination, which is a point of industry controversy.
Challenge Non-Preventable Crashes
How BASIC Scoring Works
Each BASIC score is calculated using a formula that considers three factors: the severity weight of each violation, the time weight based on when the violation occurred, and how your total weighted score compares to carriers in your safety event group. Here is how it breaks down:
Severity Weights (1-10)
Every violation type has a pre-assigned severity weight. Seatbelt violations might carry a weight of 1-2, while operating under the influence carries a weight of 10. Brake defects carry weights of 4-8 depending on the specific deficiency. Higher severity weights have a greater impact on your BASIC score.
Time Weights (1x, 2x, 3x)
Violations from the most recent 12 months are multiplied by 3. Violations from 13-24 months ago are multiplied by 2. Violations from 25-36 months are multiplied by 1 (for the Crash Indicator BASIC). This time weighting ensures that recent performance has the greatest impact on your scores and that improvement over time is reflected in declining percentiles.
Peer Group Comparison
Your total weighted score is compared against carriers with a similar number of inspections (your safety event group). This comparison generates your percentile ranking. A carrier with 10 inspections is compared to other carriers with roughly 10 inspections, not to large fleets with hundreds of inspections. This makes the comparison fair but also means small carriers are more sensitive to individual violations.
Intervention Thresholds Summary
| BASIC | General Threshold | HazMat/Passenger | FMCSA Action |
|---|---|---|---|
| Unsafe Driving | 65% | 50% | Warning letter, targeted investigation |
| HOS Compliance | 65% | 50% | Warning letter, targeted investigation |
| Driver Fitness | 65% | 50% | Warning letter, off-site investigation |
| Controlled Substances | 65% | 50% | Warning letter, on-site investigation |
| Vehicle Maintenance | 80% | 80% | Warning letter, targeted investigation |
| HazMat Compliance | 80% | 80% | Warning letter, on-site investigation |
| Crash Indicator | 65% | 50% | Crash investigation, comprehensive review |
Multiple BASICs Above Threshold = Escalated Response
How Our Team Helps Across All BASICs
At O Trucking LLC, we take a comprehensive approach to CSA management because elevated scores in any BASIC affect our carriers' ability to access freight:
Dispatch-Level HOS Protection
Every load assignment is planned around your remaining legal driving hours. We never book a load that requires pushing past the 11-hour driving limit or 14-hour on-duty window. This directly protects your HOS Compliance and Unsafe Driving BASICs by eliminating the temptation to run overtime.
BASIC Monitoring and Early Alerts
We review our carriers' SMS profiles monthly and flag any BASIC approaching the intervention threshold. Catching a trending score at 55% gives you time to take corrective action before it reaches 65% and triggers FMCSA intervention or broker restrictions.
Compliance Tracking
We track expiration dates for insurance, medical cards, CDLs, annual inspections, and registrations. Expired documents are one of the most preventable sources of CSA violations, and our tracking ensures nothing slips through the cracks. This protects your Driver Fitness BASIC and keeps you audit-ready for any FMCSA safety audit.
Keep Every BASIC Below Threshold
Our compliance-focused dispatch approach protects your CSA record across all seven BASICs. Clean scores open doors to better freight, lower insurance, and fewer inspections.