Person means an individual, firm, copartnership, corporation, company, association, joint-stock association, including any trustee, receiver, assignee, or similar representative thereof, or government, Indian tribe, or agency or instrumentality of any government or Indian tribe when it offers hazardous materials for transportation in commerce or transports hazardous materials in furtherance of a commercial enterprise, but such term does not include the United States Postal Service.
49 CFR § 397.201
This subpart prescribes procedures by which:
(1) Any person, including a State, political subdivision thereof, or Indian tribe, directly affected by any highway routing designation for hazardous materials may apply to the Administrator for a determination as to whether that highway routing designation is preempted under 49 U.S.C. 5125, or § 397.69 or § 397.203 of this part; and
(2) A State, political subdivision thereof, or Indian tribe may apply to the Administrator for a waiver of preemption with respect to any highway routing designation that the State, political subdivision thereof, or Indian tribe acknowledges to be preempted by 49 U.S.C. 5125, or § 397.69 or § 397.203 of this part, or that has been determined by a court of competent jurisdiction to be so preempted.