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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 38814, July 18, 1997, unless otherwise noted.
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| Idealized Distribution | Fine Particle Mode | Coarse Particle Mode | PM 2.5/PM 10 Ratio | FRM Sampler Expected Mass Conc. (µg/m3) | ||||
|---|---|---|---|---|---|---|---|---|
| MMD (µm) | Geo. Std. Dev. | Conc. (µg/m3) | MMD (µm) | Geo. Std. Dev. | Conc. (µg/m3) | |||
| Coarse | 0.50 | 2 | 12.0 | 10 | 2 | 88.0 | 0.27 | 13.814 |
| “Typical” | 0.50 | 2 | 33.3 | 10 | 2 | 66.7 | 0.55 | 34.284 |
| Fine | 0.85 | 2 | 85.0 | 15 | 2 | 15.0 | 0.94 | 78.539 |