---
kind: "section"
citation: "49 C.F.R. § 397.203"
title: "49"
number: "397.203"
heading: "Standards for determining preemption."
url: "https://uscodex.org/cfr/49/397.203"
---

# §397.203. Standards for determining preemption.

- (a) Any highway routing designation established, maintained, or enforced by a State, political subdivision thereof, or Indian tribe is preempted if—
  - (1) Compliance with both the highway routing designation and any requirement under the Act or of a regulation issued under the Act is not possible;
  - (2) The highway routing designation as applied or enforced creates an obstacle to the accomplishment and execution of the Act or the regulations issued under the Act; or
  - (3) The highway routing designation is preempted pursuant to [§ 397.69(b)](/cfr/49/397.69.md?p=b) of this part.
- (b) [Reserved]

## Notes

### Amendments

[57 FR 44132, Sept. 24, 1992, as amended at 59 FR 51834, Oct. 12, 1994]

### Source

Source: 57 FR 44132, Sept. 24, 1992, unless otherwise noted.

### Authority

Authority: 49 U.S.C. 322; 49 CFR 1.87. Subpart A also issued under 49 U.S.C. 5103, 31136, 31502, and 49 CFR 1.97. Subparts C, D, and E also issued under 49 U.S.C. 5112, 5125.

### Source

Source: 36 FR 4876, Mar. 13, 1971, unless otherwise noted.

### Amendments

[57 FR 44132, Sept. 24, 1992, as amended at 59 FR 51834, Oct. 12, 1994]