The Federal Motor Carrier Safety Regulations (FMCSRs) are the federal regulations that set safety and operational standards for companies operating trucks, vans, buses, and other vehicles involved in interstate commerce. TheFMCSRs apply to drivers and companies operating commercial motor vehicles (CMVs).

CMVs are highly regulated by the U.S. Department of Transportation. Rules found in the FMCSRs include those regulating drivers’ work hours, vehicle inspections and maintenance, driver training and licensing, vehicle lease agreements, insurance, vehicle marking, and a variety of other topics. The rules are enforced by the Federal Motor Carrier Safety Administration (FMCSA) and its state partners.

The FMCSRs are found in the Code of Federal Regulations (CFR) under Title 49, which contains all regulations of the U.S. Department of Transportation. Within Title 49, the FMCSRs are found in Subtitle 3, Chapter III, Subchapter B, consisting of Parts 350 through 399. Other parts typically associated with motor carriers include Part 40, related to drug/alcohol testing, and Part 325, the noise emission standards. Parts 356 through 379 are regulations from the former Interstate Commerce Commission (ICC), now administered by the FMCSA and commonly referred to as “economic” or “commercial” regulations.

Though the FMCSRs apply only to interstate commerce (relating to cargo or passengers that cross state lines), many states adopt all or a portion of the FMCSRs and apply them to vehicles operating strictly within state boundaries.