40 CFR § 97.80 - Applicability.

---
identifier: "/us/cfr/t40/s97.80"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "40 CFR § 97.80 - Applicability."
title_number: 40
title_name: "Protection of Environment"
section_number: "97.80"
section_name: "Applicability."
chapter_name: "ENVIRONMENTAL PROTECTION AGENCY"
subchapter_number: "C"
subchapter_name: "AIR PROGRAMS"
part_number: "97"
part_name: "FEDERAL NOX BUDGET TRADING PROGRAM, CAIR NOX AND SO2 TRADING PROGRAMS, CSAPR NOX AND SO2 TRADING PROGRAMS, AND TEXAS SO2 TRADING PROGRAM"
positive_law: false
currency: "2026-03-24"
last_updated: "2026-03-24"
format_version: "1.1.0"
generator: "[email protected]"
authority: "42 U.S.C. 7401, 7403, 7410, 7426, 7491, 7601, and 7651,"
regulatory_source: "65 FR 2727, Jan. 18, 2000, unless otherwise noted. 71 FR 25396, 25422, and 25443, Apr. 28, 2006"
cfr_part: "97"
---


# 97.80 Applicability.

A unit that is in a State (as defined in § 97.2), is not a NO<sub>X</sub> Budget unit under § 97.4(a), is not a unit exempt under § 97.4(b), vents all of its emissions to a stack, and is operating, may qualify to be a NO<sub>X</sub> Budget opt-in unit under this subpart. A unit that is a NO<sub>X</sub> Budget unit under § 97.4(a), is covered by an exemption under § 97.4(b) or § 97.5 that is in effect, or is not operating is not eligible to be a NO<sub>X</sub> Budget opt-in unit.