---
kind: "section"
citation: "40 C.F.R. § 97.281"
title: "40"
number: "97.281"
heading: "General."
url: "https://uscodex.org/cfr/40/97.281"
---

# §97.281. General.

- (a) Except as otherwise provided in [§§ 97.201 through 97.204](/cfr/40/97.201..97.204.md), [§§ 97.206 through 97.208](/cfr/40/97.206..97.208.md), and subparts [BBB](/cfr/40/subpartBBB.md) and [CCC](/cfr/40/subpartCCC.md) and subparts [FFF](/cfr/40/subpartFFF.md) through [HHH](/cfr/40/subpartHHH.md) of this part, a CAIR SO2 opt-in unit shall be treated as a CAIR SO2 unit for purposes of applying such sections and subparts of this part.
- (b) Solely for purposes of applying, as provided in this subpart, the requirements of [subpart HHH](/cfr/40/subpartHHH.md) of this part to a unit for which a CAIR opt-in permit application is submitted and not withdrawn and a CAIR opt-in permit is not yet issued or denied under this subpart, such unit shall be treated as a CAIR SO2 unit before issuance of a CAIR opt-in permit for such unit.

## Notes

### Authority

Authority: 42 U.S.C. 7401, 7403, 7410, 7426, 7491, 7601, and 7651, et seq.

### Source

Source: 65 FR 2727, Jan. 18, 2000, unless otherwise noted. 71 FR 25396, 25422, and 25443, Apr. 28, 2006