Part 390 — Federal Motor Carrier Safety Regulations: General

49 CFR Part 390: The foundational definitions and general applicability rules for all FMCSRs.

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Overview

49 CFR Part 390 is the foundational part of the Federal Motor Carrier Safety Regulations — it establishes the definitions used throughout Parts 391-399 and sets the general applicability rules that determine which carriers, drivers, and vehicles are subject to FMCSA regulation. Before any other part of the FMCSRs applies, Part 390 determines whether it applies at all.

The most critical definition in Part 390 is “commercial motor vehicle” (CMV). Under FMCSA’s definition, a CMV is any self-propelled or towed vehicle used in interstate commerce that has a gross vehicle weight rating (GVWR) or gross combination weight rating (GCWR) over 10,001 lbs, is designed to transport 9 or more passengers for compensation, is designed to transport 16 or more passengers regardless of compensation, or is used in transporting hazardous materials in a quantity requiring placards. This definition determines whether the FMCSRs apply to a given vehicle.

Part 390 additionally sets the general coercion prohibition — the rule that carriers, shippers, and brokers cannot pressure drivers to violate federal safety regulations. Drivers who report coercion are protected from retaliation, and entities found to have coerced drivers face civil penalties.

Key Provisions

Defines “commercial motor vehicle” — the threshold definition that triggers application of FMCSRs.
Establishes key definitions used throughout Parts 391-399: employer, employee, motor carrier, on-duty time, and more.
Sets general applicability rules including which operations are exempt from specific FMCSR requirements.
Prohibits carrier, shipper, and broker coercion of drivers to violate safety regulations.
Requires carriers and drivers to know and comply with all applicable FMCSRs.

Why It Matters to Truck Owners

Part 390 is where you start when determining whether FMCSA rules apply to a vehicle or operation. If you’re unsure whether a truck you own or are considering buying is a CMV under FMCSA’s definition, Part 390 provides the answer. The definitions here also affect how other rules apply — for example, the definition of “on-duty time” in Part 390 directly shapes how hours of service under Part 395 are calculated.

Frequently Asked Questions

What is a commercial motor vehicle (CMV) under FMCSA?

Under 49 CFR 390.5, a CMV is a vehicle used in interstate commerce that weighs over 10,001 lbs GVWR/GCWR, is designed to carry 9 or more passengers for compensation or 16 or more passengers total, or carries hazardous materials in placardable quantities. Vehicles meeting this definition are subject to the full FMCSR regime.

Are there exemptions from the FMCSRs under Part 390?

Yes — Part 390 identifies several categories of vehicles and operations that are partially or fully exempt from FMCSRs, including farm vehicles operated within 150 air miles of the farm, certain utility vehicles, and others. The specific exemptions are detailed in Part 390 and vary by which FMCSR part is at issue.

What is the coercion prohibition in Part 390?

Part 390 prohibits motor carriers, shippers, receivers, and transportation intermediaries from coercing or threatening drivers to operate in violation of federal safety regulations. Drivers who report coercion are protected from retaliation. Violations by carriers or other parties can result in civil penalties.

Read the official legal text: 49 CFR Part 390 — eCFR.gov (official)

Related Federal Trucking Laws

This page is provided for informational purposes only and is not legal advice. Always verify current requirements at fmcsa.dot.gov or with a qualified transportation attorney.

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