Table 4 Levels of fine particulate (PM2.5) air pollution in units of micrograms per cubic meter ((μg/m3) and corresponding U.S. health advisory descriptors with accompanying simplified color code (USEPA, 1999).
From: Air pollution in Boston bars before and after a smoking ban
PM2.5 (μg/m3) AQI Break-points | Air Quality Index | Category | Color Code |
|---|---|---|---|
0.0 – 15.4 | 0 – 50 | Good | Green |
15.5 – 40.4 | 51 – 100 | Moderate | Yellow |
40.5 – 65.4 | 101 – 150 | Unhealthy SG* | Orange |
65.5 – 150.4 | 151 – 200 | Unhealthy | Red |
150.5 – 250.4 | 201 – 300 | Very unhealthy | Violet |
250.5 – 350.4 | 301 – 400 | Hazardous | Maroon |
350.5 – 500.4 | 401 – 500 | Very Hazardous | Maroon |
> 505 | 500 | (Significant Harm) | ** |