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EPA \ TAQMN \ Air Quality Monitoring \ AQI

AQI

The definition of air pollution indicators

Air quality index based on monitoring data will be on the same day in the air ozone(O3), suspended fine particles(PM2.5), suspended particles(PM10), carbon monoxide(CO), sulfur dioxide(SO2) and II Nitric oxide(NO2) such as the concentration of value, its impact on human health, were converted into different pollutants The vice-value targets, indicators, deputy to the day of the maximum value of the stations on the day of the air quality index (AQI).

The concentration of pollutants and air quality index value deputy table

Air Quality Index(AQI)
AQI O3
(ppm)
8hr
O3
(ppm)
1-hr(1)
PM2.5
(μg/m3 )
24-hr
PM10
(μg/m3 )
24-hr  
CO
(ppm)
8-hr
SO2
(ppb)
1-hr
NO2
(ppb)
1-hr
Good
0~50
0.000 - 0.054 - 0.0 - 15.4 0 - 54 0 - 4.4 0 - 35 0 - 53
Moderate
51~100
0.055 - 0.070 - 15.5 - 35.4 55 - 125 4.5 - 9.4 36 - 75 54 - 100
Unhealthy for
Sensitive Groups
101~150
0.071 - 0.085 0.125 - 0.164 35.5 - 54.4 126 - 254 9.5 - 12.4 76 - 185 101 - 360
Unhealthy
151~200
0.086 - 0.105 0.165 - 0.204 54.5 - 150.4 255 - 354 12.5 - 15.4 186 - 304(3) 361 - 649
Very Unhealthy
201~300
0.106 - 0.200 0.205 - 0.404 150.5 - 250.4 355 - 424 15.5 - 30.4 305 - 604(3) 650 - 1249
Hazardous
301~400
(2) 0.405 - 0.504 250.5 - 350.4 425 - 504 30.5 - 40.4 605 - 804(3) 1250 - 1649
Hazardous
401~500
(2) 0.505 - 0.604 350.5 - 500.4 505 - 604 40.5 - 50.4 805 -1004(3) 1650 - 2049
  1. Areas are generally required to report the AQI based on 8-hour ozone values. However, there are a small number of areas where an AQI based on 1-hour ozone values would be more precautionary. In these cases, in addition to calculating the 8-hour ozone index value, the 1-hour ozone value may be calculated, and the maximum of the two values reported.
  2. 8-hour O3 values do not define higher AQI values (≥ 301). AQI values of 301 or higher are calculated with 1-hour O3 concentrations.
  3. 1-hour SO2 values do not define higher AQI values (≥ 200). AQI values of 200 or greater are calculated with 24-hour SO2 concentrations.

AQI value and impact on health

AQI Air Quality Index
(AQI)
0~50 51~100 101~150 151~200 201~300 301~500
Impact
on Health
Good Moderate Unhealthy for Sensitive Groups Unhealthy Very Unhealthy Hazardous
Status Color            
Impact on Human Health Air quality is considered satisfactory, and air pollution poses little or no risk. Air quality is acceptable; however, for some pollutants there may be a moderate health concern for a very small number of people who are unusually sensitive to air pollution. Members of sensitive groups may experience health effects. The general public is not likely to be affected. Everyone may begin to experience health effects; members of sensitive groups may experience more serious health effects. Health alert: everyone may experience more serious health effects. Health warnings of emergency conditions. The entire population is more likely to be affected.

Air Quality Index and Activity Guidance

Air Quality Index
(AQI)
0~50 51~100 101~150 151~200 201~300 301~500
Air Quality Index Levels
of Health Concern
Good Moderate Unhealthy for Sensitive Groups Unhealthy Very Unhealthy Hazardous
Status Color Green Yellow Orange Red Purple Maroon
Activity Guidance
for the
General Public
Enjoy your usual outdoor activities. Enjoy your usual outdoor activities. 1.Everyone experiencing discomfort such as sore eyes, cough or sore throat should consider reducing outdoor activities.
2.For students, it’s ok to be active outside, but are recommended to reduce prolonged strenuous exercise.
1.Everyone experiencing discomfort such as sore eyes, cough or sore throat should reduce physical exertion, particularly outdoors.
2.Students should avoid prolonged strenuous exercise, and take more breaks during outdoor activities.
1.Everyone should reduce outdoor activities.
2.Students should stop outdoor activities and move all activities and classes indoors.
1.Everyone should avoid outdoor activities and keep doors and windows closed. If it is necessary to go out, please wear a mask.
2.Students should stop outdoor activities and move all activities and classes indoors.
Activity Guidance
 for Sensitive Groups
Enjoy your usual outdoor activities. Unusually sensitive groups are recommended to watch for symptoms such as coughing or shortness of breath, but can still be active outside.
 
1.People with heart, respiratory and cardiovascular problems, children, teenagers and older adults are recommended to reduce physical exertion and outdoor activities.
2.People with asthma may need to use their reliever inhalers more often.
1.People with heart, respiratory and cardiovascular problems, children, teenagers and older adults are recommended to stay indoors and reduce physical exertion. If it is necessary to go out, please wear a mask.
2.People with asthma may need to use their reliever inhalers more often.
1.People with heart, respiratory and cardiovascular problems, children, teenagers and older adults should stay indoors and reduce physical exertion. If it is necessary to go out, please wear a mask.
2.People with asthma should use their reliever inhalers more often.
1.People with heart, respiratory and cardiovascular problems, children, teenagers and older adults should stay indoors and avoid physical exertion. If it is necessary to go out, please wear a mask.
2.People with asthma should use their reliever inhalers more often.

last update : 2017/07/31

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