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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
Does § 393.41 prohibit air brake systems from being equipped with a means to release the spring brakes for purposes of towing disabled vehicles in emergency situations? FMCSA-VEH-393.41-Q02 Releasing spring brakes for towing
What difference, if any, is there between a warning device and a warning signal? FMCSA-VEH-393.51-Q05 What’s the difference between a warning device and a warning signal?
Is a heat shield mandatory on a vertical exhaust stack? FMCSA-VEH-393.83-Q01 Heat shield on vertical exhaust stack?
May a driver domiciled in the United States comply with the Canadian hours of service regulations while driving in Canada? FMCSA-HOS-395.3-Q05 Hours of Service Maximum Driving Time
Do Canadian Provincial inspections meet FMCSA standards? FMCSA-VM-396.17-Q10.cm Do Canadian Provincial inspections meet FMCSA standards?
Question 2: Is there a specific form or format to be used in ensuring that inspectors are qualified in accordance with § 396.19? FMCSA-VM-396.19-Q02.cm Is there an inspector qualification form?
Question 3: Who has the responsibility of inspecting and maintaining leased vehicles and their maintenance records? FMCSA-VM-396.3-Q003 Vehicle inspection, repair and maintenance
Does the government exception in §390.3T(f)(2) apply to motor carriers doing business with the government? FMCSA-RG-390.3T-Q001 Government Exception application
Do the disqualification provisions of §391.15 apply to offenses committed by a driver who is using a company vehicle for personal reasons while off-duty? FMCSA-DQ-391.15-Q005 Driver disqualification
A driver used by a motor carrier operates a CMV to and from his/her residence out of State. Is this considered interstate commerce? FMCSA-RG-390.5T-Q005 Extent of “interstate commerce” when applied to personal conveyance