---
kind: "section"
citation: "23 C.F.R. § 490.503"
title: "23"
number: "490.503"
heading: "Applicability."
url: "https://uscodex.org/cfr/23/490.503"
---

# §490.503. Applicability.

- (a) The performance measures are applicable to those portions of the mainline highways on the NHS as provided in paragraphs [(a)(1)](#a-1) and [(2)](#a-2) of this section (and in more detail in [§ 490.507](/cfr/23/490.507.md)):
  - (1) The Travel Time Reliability measures in [§ 490.507(a)](/cfr/23/490.507.md?p=a) are applicable to all directional mainline highways on the Interstate System and non-Interstate NHS.
  - (2) [Reserved]
- (b) [Reserved]

## Notes

### Amendments

[82 FR 6031, Jan. 18, 2017, as amended at 83 FR 24936, May 31, 2018; 88 FR 85392, Dec. 7, 2023; 90 FR 16466, Apr. 18, 2025]

### Source

Source: 82 FR 6042, Jan. 18, 2017, unless otherwise noted.

### Authority

Authority: 23 U.S.C. 134, 135, 148(i) and 150; 49 CFR 1.85.

### Source

Source: 81 FR 13913, Mar. 15, 2016, unless otherwise noted.

### Amendments

[82 FR 6031, Jan. 18, 2017, as amended at 83 FR 24936, May 31, 2018; 88 FR 85392, Dec. 7, 2023; 90 FR 16466, Apr. 18, 2025]