DOT compliance
“DOT compliance” is not one rule. It is a set of parts in Title 49 of the Code of Federal Regulations, each covering something different, and most compliance questions are really questions about which part applies. This is the map, with the official part titles.
| Part | Official title |
|---|---|
| 49 CFR 382 | Controlled Substances and Alcohol Use and Testing |
| 49 CFR 383 | Commercial Driver's License Standards; Requirements and Penalties |
| 49 CFR 387 | Minimum Levels of Financial Responsibility for Motor Carriers |
| 49 CFR 390 | Federal Motor Carrier Safety Regulations; General |
| 49 CFR 391 | Qualifications of Drivers and Longer Combination Vehicle (LCV) Driver Instructors |
| 49 CFR 392 | Driving of Commercial Motor Vehicles |
| 49 CFR 393 | Parts and Accessories Necessary for Safe Operation |
| 49 CFR 395 | Hours of Service of Drivers |
| 49 CFR 396 | Inspection, Repair, and Maintenance |
| 49 CFR 397 | Transportation of Hazardous Materials; Driving and Parking Rules |
| 49 CFR 399 | Employee Safety and Health Standards |
Part titles taken verbatim from the Electronic Code of Federal Regulations. The summaries below are this page’s own plain-language description, not the regulation’s wording.
What each part is actually for
49 CFR 382
Controlled Substances and Alcohol Use and Testing
Who must be tested, when, and what happens after a positive result.
49 CFR 383
Commercial Driver's License Standards; Requirements and Penalties
What licence a driver needs, what endorsements cover, and disqualifications.
49 CFR 387
Minimum Levels of Financial Responsibility for Motor Carriers
The insurance minimums, which vary by what is being hauled.
49 CFR 390
Federal Motor Carrier Safety Regulations; General
Definitions, who the rules apply to, USDOT registration and vehicle marking. Read the detail.
49 CFR 391
Qualifications of Drivers and Longer Combination Vehicle (LCV) Driver Instructors
Driver qualification files: what goes in one and how long it is kept.
49 CFR 392
Driving of Commercial Motor Vehicles
Conduct behind the wheel, and the pre-driving equipment check. Read the detail.
49 CFR 393
Parts and Accessories Necessary for Safe Operation
The equipment standards a vehicle is measured against at inspection.
49 CFR 395
Hours of Service of Drivers
Driving limits, duty windows, breaks and records of duty status. Read the detail.
49 CFR 396
Inspection, Repair, and Maintenance
Systematic maintenance, driver inspection reports and repair certification. Read the detail.
49 CFR 397
Transportation of Hazardous Materials; Driving and Parking Rules
Routing, attendance and parking rules specific to hazmat loads.
49 CFR 399
Employee Safety and Health Standards
Step, handhold and deck requirements for safe access to vehicles.
The two parts people mix up
Part 391 is drivers — qualification files, medical certificates, the paperwork that says a person may operate. Part 396 is vehicles — inspection, repair and maintenance. Searching the wrong one for a maintenance rule returns nothing useful, and the numbers are close enough together to make that easy to do.
Similarly, Part 392 governs driving conduct including the check before driving, while Part 393 sets the equipment standards the vehicle is measured against. One is about what the driver does; the other is about what the truck has.
Whether any of it applies to you
All of the above assumes the vehicle meets the definition of a commercial motor vehicle in 49 CFR 390.5 — which turns on the combination weight rather than the truck, and catches a great many operations that do not think of themselves as regulated. Where that threshold sits.
What is not on this page
CSA scores and the Safety Measurement System are not here. They are an FMCSA programme rather than a regulation, so there is no CFR text to quote, and the FMCSA pages describing the methodology were not reachable when this page was written. Publishing BASIC thresholds from memory would put a conclusion about your own safety standing in front of you with no way to tell it was wrong. FMCSA remains the place to read those.
Part titles retrieved from the Electronic Code of Federal Regulations at ecfr.gov. A reference, not legal advice — and this page makes no assessment of whether any particular operation complies.
Tezify holds driver files, inspection reports and duty records in one system, with expiry dates surfaced before they lapse. See what it does.