40 CFR § 81.171 - Missoula Intrastate Air Quality Control Region.
---
identifier: "/us/cfr/t40/s81.171"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "40 CFR § 81.171 - Missoula Intrastate Air Quality Control Region."
title_number: 40
title_name: "Protection of Environment"
section_number: "81.171"
section_name: "Missoula Intrastate Air Quality Control Region."
chapter_name: "ENVIRONMENTAL PROTECTION AGENCY"
subchapter_number: "C"
subchapter_name: "AIR PROGRAMS"
part_number: "81"
part_name: "DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES"
positive_law: false
currency: "2026-04-05"
last_updated: "2026-04-05"
format_version: "1.1.0"
generator: "[email protected]"
authority: "42 U.S.C. 7401,"
regulatory_source: "36 FR 22421, Nov. 25, 1971, unless otherwise noted."
cfr_part: "81"
---
# 81.171 Missoula Intrastate Air Quality Control Region.
The Missoula Intrastate Air Quality Control Region (Montana) consists of the territorial area encompassed by the boundaries of the following jurisdictions or described area (including the territorial area of all municipalities (as defined in section 302(f) of the Clean Air Act, 42 U.S.C. 1857h(f)) geographically located within the outermost boundaries of the area so delimited):
In the State of Montana: Flathead County, Lake County, Lincoln County, Mineral County, Missoula County, Ravalli County, Sanders County.