40 CFR § 81.175 - San Isabel Intrastate Air Quality Control Region.
---
identifier: "/us/cfr/t40/s81.175"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "40 CFR § 81.175 - San Isabel Intrastate Air Quality Control Region."
title_number: 40
title_name: "Protection of Environment"
section_number: "81.175"
section_name: "San Isabel 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"
---
# 81.175 San Isabel Intrastate Air Quality Control Region.
The San Isabel Intrastate Air Quality Control Region (Colorado) 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 Colorado: Chaffee County, Custer County, El Paso County, Fremont County, Huerfano County, Lake County, Las Animas County, Park County, Pueblo County, Teller County.