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Which CMV definition should you use?

Guessing wrong may result in fines and penalties

Posted May 7, 2018

The Federal Motor Carrier Safety Regulations (FMCSRs) have two definitions of commercial motor vehicle (CMV), leaving some readers wondering when to use each. A misunderstanding of which vehicles and drivers are subject to specific FMCSRs could result in serious violations and fines.

Let’s look at the regs

Interstate motor carriers need to look at Section 390.5. It indicates “Unless specifically defined elsewhere, in this subchapter” the definitions provided in the section apply. One of the definitions provided is “commercial motor vehicle.”

Section 390.5 defines a commercial motor vehicle as “any self-propelled or towed motor vehicle used on a highway in interstate commerce to transport passengers or property when the vehicle— (1) Has a gross vehicle weight rating or gross combination weight rating, or gross vehicle weight or gross combination weight, of 4,536 kg (10,001 pounds) or more, whichever is greater; or (2) Is designed or used to transport more than 8 passengers (including the driver) for compensation; or (3) Is designed or used to transport more than 15 passengers, including the driver, and is not used to transport passengers for compensation; or (4) Is used in transporting material found by the Secretary of Transportation to be hazardous under 49 U.S.C. 5103 and transported in a quantity requiring placarding under regulations prescribed by the Secretary under 49 CFR, subtitle B, chapter I, subchapter C.”

What does ‘this subchapter’ mean?

When Section 390.5 uses the word “subchapter,” you have to look at the U.S. Code of Federal Regulations (CFR) Title 49, Transportation — which is broken up by mode. The Federal Motor Carrier Safety Administration (FMCSA) rules are found in Subtitle B, Volume 5, Chapter III of Title 49. Within Chapter III, you have Subchapters A and B. Subchapter B is essentially Parts 350-399.

Using the verbiage from Section 390.5, unless specified in Parts 350-399 (the subchapter), the term CMV is referencing the definition in Section 390.5. Based on this, the driver and vehicle are subject to driver qualifications, vehicle inspection and maintenance, equipment, USDOT numbers/markings, insurance, hours of service, and the like.

The regulations have a few instances of when a CMV definition would differ from Section 390.5. Parts 383, 382, and 380 have their own definition of commercial motor vehicle (i.e., specifically defined elsewhere). Basically, these definitions include only vehicles that require a commercial driver’s license (CDL).

Intrastate-only vehicles

For intrastate commerce, a state has the option of adopting its own definitions for its version of the safety regulations. The weight thresholds for intrastate-only vehicles vary greatly, often mimicking the federal standard of 10,001 pounds or tying it into the need for a CDL. Yet other states have adopted weights completely unrelated to any federal rule (e.g., 18,001 pounds).

Federal Motor Carrier Safety Regulations PocketbookJ. J. Keller's Federal Motor Carrier Safety Regulations Pocketbook gives your drivers easy access to word-for-word Federal Motor Carrier Safety Regulations (FMCSRs) in a convenient pocketbook format.


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