Concentration of SO2, µg/m3 | Levels in terms of human health | Precautions |
0 - 50 | Good | - |
51 - 100 | Reasonable | - |
101 - 150 | Unhealthy for sensitive groups | Asthmatic people should limit physical exertion outdoors in these areas. |
151 - 200 | Insalubrious
| Children, asthmatics and people with heart or lung diseases should limit physical exertion in outdoor areas. |
201 - 300 | Insalubrious
| Physical exertion should be avoided in these outdoor areas for children, asthmatics, and people with heart or lung diseases. It is recommended that you also avoid physical efforts in these areas. |
301 - 500 | Very toxic | Children, asthmatics and people with heart or lung diseases should stay indoors; other individuals should avoid outdoor efforts. |