Air Quality Index Classes - Siemens QSA2700D Basic Documentation

Air Quality Index classes

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7 Air Quality Index classes
22 | 26
Siemens
The Siemens fine dust sensor QSA2700D displays:
● The PM2.5 reading in μg/m
● The AQI (Air Quality Index)
The AQI is a number used by government agencies to communicate to the public
how polluted the air currently is or a forecast of air quality.
The AQI category (good, moderate, unhealthy, etc.) is based on the AQI (see
Table 1) and is represented by a range of colors (green = good, orange = poor,
etc.).
In general, AQI is calculated based on multiple pollutants: PM2.5, PM10, ozone,
NO2, SO2, and CO.
However, the AQI value is always based on the Individual Air Quality Index (IAQI)
of the main pollutant. For example, PM2.5 is the main pollutant in China during the
winter, and the locally reported AQI is the IAQI of PM2.5.
AQI is a non-dimensional value. In contrast, PM2.5 values have the dimensional
unit μg/m . Consequently, there is a numerical table to convert pollutant PM2.5 in
3
μg/m to AQI. This is outlined in Table 1 where, for example, "AQI 1...50, Good"
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represents a different range of values of PM2.5 in the U.S. (1...12 μg/m
China (1...35 μg/m )
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These different conversions of PM2.5 to AQI, country by country, are reflected by
different AQI classes. Our new sensor QSA2700D for PM2.5 recognizes three
different classes that can be selected during product commissioning:
● Class I – U.S.
● Class II – China
● Class III – India
For European countries, we recommend selecting class I.
Table 1: AQI for U.S., China, and India
US
AQI PM2.5 Category
(μg/m )
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1-50 1-12.0 Good
51-100 12.1-35.4 Moderate
101-150 35.5-55.4 Unhealthy
for
sensitive
group
151-200 55.5-150.4 Unhealthy
201-300
150.5- Very
250.4 unhealthy
300+ 250.5+ Hazardous 185+
Further reference:
Europe: http://www.airqualitynow.eu/about_indices_definition.php
Real-time AQI worldwide:
Real-time AQI Europe:
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China
PM2.5 Category
(μg/m )
3
1-35 Good
36-75 Moderate
76-115 Unhealthy
for
sensitive
group
116-150 Unhealthy
151-185
Very
unhealthy
Hazardous 351-430
http://aqicn.org/map/world/
http://aqicn.org/map/europe/
) and
3
India
PM2.5 Category AQI
(μg/m )
3
0-50 Good 1-50
51-100 Satisfactory 51-100
101-250 Moderate 101-200
polluted
251-350 Poor 201-300
Very poor 301-400
430+ Severe 401-500
A6V11160936_en--_a
2017-12-01