Siemens AQS2700, Основная документация

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Air Quality Index classes
7
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7 Air Quality Index classes
The Siemens fine dust sensor QSA2700D displays:
● The PM2.5 reading in μ g/m
3
● 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 μ g/m
3
. Consequently, there is a numerical table to convert pollutant PM2.5 in
μ g/m
3
to AQI. This is outlined in Table 1 where, for example, "AQI 1…50, Good"
represents a different range of values of PM2.5 in the U.S. (1…12 μ g/m
3
) and
China (1…35 μ g/m
3
)
These different conversions of PM2.5 to AQI, country by country, are reflected by
different AQI classes. The 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 China India
AQI PM2.5
( μ g/m
3
)
Category PM2.5
( μ g/m
3
)
Category PM2.5
( μ g/m
3
)
Category AQI
1-50 1-12.0 Good 1-35 Good 0-50 Good 1-50
51-100 12.1-35.4 Moderate 36-75 Moderate 51-100 Satisfactory 51-100
101-150 35.5-55.4 Unhealthy
for
sensitive
group
76-115 Unhealthy
for
sensitive
group
101-250 Moderate
polluted
101-200
151-200 55.5-150.4 Unhealthy 116-150 Unhealthy
201-300
150.5-
250.4
Very
unhealthy
151-220
Very
unhealthy
251-350 Unhealthy 201-300
300+ 250.5+ Hazardous 220+ Hazardous 351-430 Very
unhealthy
301-400
430+ Hazardous 401-500
Further reference:
Europe:
http://www.airqualitynow.eu/about_indices_definition.php
Real-time AQI worldwide: http://aqicn.org/map/world/
Real-time AQI Europe: http://aqicn.org/map/europe/