Table 4.
Possible PM2.5 AQI categories for region.35
| PM2.5 Standard (µg/m3) | 1997 USEPA NAAQS | 2006 USEPA NAAQS | 2007 WHO Guidelines | |||
| Daily | 65 | Daily | 35 | Daily | 25 | |
| Annual | 15 | Annual | 15 | Annual | 10 | |
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