DOT Rule 49 CFR Part 40 Section 40.7
Subpart A - Administrative Provisions
§ 40.7 How can you get an exemption from a requirement in this regulation?
(a) If you want an exemption from any provision of this part, you must request it in writing from the Office of the Secretary of Transportation, under the provisions and standards of 49 CFR part 5. You must send requests for an exemption to the following address: Department of Transportation, Deputy Assistant General Counsel for Regulation and Enforcement, 1200 New Jersey Avenue, SE, Washington, DC 20590.
(b) Under the standards of 49 CFR part 5, we will grant the request only if the request documents special or exceptional circumstances, not likely to be generally applicable and not contemplated in connection with the rulemaking that established this part, that make your compliance with a specific provision of this part impracticable.
(c) If we grant you an exemption, you must agree to take steps we specify to comply with the intent of the provision from which an exemption is granted.
(d) We will issue written responses to all exemption requests.
[65 FR 79526, Dec. 19, 2000, as amended at 73 FR 33329, June 12, 2008]