---
kind: "section"
citation: "49 C.F.R. § 325.21"
title: "49"
number: "325.21"
heading: "Scope of the rules in this subpart."
url: "https://uscodex.org/cfr/49/325.21"
---

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


The rules in this subpart specify criteria for sound level measurement systems which are used to make the sound level measurements specified in subpart D and subpart E of this part.


## 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.