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Sec. 301(a) of the Clean Air Act (42 U.S.C. sec. 1857g(a)), as amended by sec. 15(c)(2) of Pub. L. 91-604, 84 Stat. 1713, unless otherwise noted.
40 FR 7049, Feb. 18, 1975, unless otherwise noted.
62 FR 38784, July 18, 1997, unless otherwise noted.
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| Pollutant | Reference or equivalent | Manual or automated | Applicable
appendix of part 50 of this chapter |
Applicable subparts of this part | |||||
|---|---|---|---|---|---|---|---|---|---|
| A | B | C | D | E | F | ||||
| SO2 | Reference | Manual | A-2 | ||||||
| Automated | A-1 | ✓ | ✓ | ||||||
| Equivalent | Manual | A-1 | ✓ | ✓ | |||||
| Automated | A-1 | ✓ | ✓ | ✓ | |||||
| CO | Reference | Automated | C | ✓ | ✓ | ||||
| Equivalent | Manual | C | ✓ | ✓ | |||||
| Automated | C | ✓ | ✓ | ✓ | |||||
| O3 | Reference | Automated | D | ✓ | ✓ | ||||
| Equivalent | Manual | D | ✓ | ✓ | |||||
| Automated | D | ✓ | ✓ | ✓ | |||||
| NO2 | Reference | Automated | F | ✓ | ✓ | ||||
| Equivalent | Manual | F | ✓ | ✓ | |||||
| Automated | F | ✓ | ✓ | ✓ | |||||
| Pb | Reference | Manual | G | ||||||
| Equivalent | Manual | G | ✓ | ✓ | |||||
| Automated | G | ✓ | ✓ | ||||||
| PM10-Pb | Reference | Manual | Q | ||||||
| Equivalent | Manual | Q | ✓ | ✓ | |||||
| Automated | Q | ✓ | ✓ | ||||||
| PM10 | Reference | Manual | J | ✓ | ✓ | ||||
| Equivalent | Manual | J | ✓ | ✓ | ✓ | ||||
| Automated | J | ✓ | ✓ | ✓ | |||||
| PM2.5 | Reference | Manual | L | ✓ | ✓ | ||||
| Equivalent Class I | Manual | L | ✓ | ✓ | ✓ | ||||
| Equivalent Class II | Manual | L 1 | ✓ | 2 ✓ | ✓ | 1 2 ✓ | |||
| Equivalent Class III | Automated | L 1 | ✓ | ✓ | ✓ | 1 ✓ | |||
| PM10-2.5 | Reference | Manual | L,2 O | ✓ | ✓ | ||||
| Equivalent Class I | Manual | L,2 O | ✓ | ✓ | ✓ | ||||
| Equivalent Class II | Manual | L,2 O | ✓ | 2 ✓ | ✓ | 1,2 ✓ | |||
| Equivalent Class III | Automated | 1 L, 1 2 O | ✓ | ✓ | ✓ | 1 ✓ | |||
| 1 Some requirements may apply, based on the nature of each particular candidate method, as determined by the Administrator. | |||||||||
| 2 Alternative Class III requirements may be substituted. | |||||||||
[89 FR 16382, Mar. 6, 2024]