---
kind: "section"
citation: "49 C.F.R. § 325.31"
title: "49"
number: "325.31"
heading: "Scope of the rules in this subpart."
url: "https://uscodex.org/cfr/49/325.31"
---

# §325.31. Scope of the rules in this subpart.


The rules in this subpart specify conditions and procedures for measurement of the sound level generated by a motor vehicle engaged in a highway operation for the purpose of ascertaining whether the motor vehicle conforms to the Standards for Highway Operations set forth in [40 CFR 202.20](/cfr/40/202.20.md).


## Notes

### Authority

Authority: 42 U.S.C. 4917; 49 U.S.C. 301; and 49 CFR 1.87.

### Source

Source: 40 FR 42437, Sept. 12, 1975, unless otherwise noted.