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Regulatory Guidance

Welcome to the FMCSA Guidance Portal. This web portal is a searchable, indexed database that contains and links to all guidance documents in effect from the Federal Motor Carrier Safety Administration. The guidance documents lack the force and effect of law, unless expressly authorized by statute or incorporated into a contract.

To comment on any guidance document, or to request issuance, reconsideration, modification, or rescission of any guidance document, please identify the guidance document in your request and send it to: FMCSAguidance@dot.gov. NOTE: The FMCSAguidance mailbox is not intended to serve as a mailbox for general inquiries. For inquiries that go beyond the limited purpose of the FMCSAguidance mailbox, please call FMCSA's Information Line (800-832-5660) or visit FMCSA's "Contact Us" page to send your inquiry to the appropriate mailbox.

Subject Agency Identifier Topic Issued Date
When two safety chains are used, must the ultimate combined breaking strength of each chain be equal to the gross weight of the towed vehicle(s) or would the requirements be met if the combined breaking strength of the two chains is equal to the gross wei FMCSA-VEH-393.70-Q02 Required strength of safety chains
Do the rules for protection against shifting or falling cargo apply to CMVs with enclosed cargo areas? FMCSA-VEH-393.100-Q02 Do the rules on shifting or falling cargo apply to enclosed trucks and trailers?
Under the DOT rules, must an SAP be certified by the DOT in order to perform SAP functions? FMCSA-D&A-382.605-Q3 SAP Certification Rules
Are carriers liable for the actions of their employees even though the carrier contends that it did not require or permit the violations to occur? FMCSA-HOS-395.3-Q08 Hours of Service Maximum Driving Tim
Do electronic devices which are advertised as radar jammers meet the definition of a radar detector in 49 CFR 390.5T? FMCSA-RG-390.5T-Q021 Radar jammers as radar detectors
Question 3: Is a motor carrier required to accept a certificate from the driver’s regularly employing motor carrier certifying that the driver is qualified per §391.65? FMCSA-DQ-391.65-Q003 Drivers furnished by other motor carriers
Do the definitions of "farm", "farmer" and "agricultural crops" apply to greenhouse operations? FMCSA-RG-390.5T-Q001 Applicability of farm-related definitions to greenhouse operations
Are trailers which are stacked upon each other and drawn by a motor vehicle by attachment to the bottom trailer, a driveaway-towaway operation? FMCSA-RG-390.5T-Q024 Stacked trailers in driveaway-towaway operations
Question 13: Can random testing be substituted for required follow-up testing? FMCSA-D&A-382.605-Q13 Drug & Alcohol Testing – Random Testing in Lieu of Follow-up Testing
Is the driver required to record meal and other routine stops as off-duty time, or is it the driver’s decision whether such time is recorded as off-duty? FMCSA-HOS-395.2-Q03 Hours of Service Definitions