AHMEDABAD: Sunday proved to be
an exception, nationally, on the
Central Pollution Control Board
(CPCB) daily air quality index (AQI)
list. Ahmedabad displaced Delhi in
the rank to become the second city
with a poor ambient air quality in
the country.
The AQI index defined the city's air
quality to be "very poor" along with
Faridabad. The AQI score for
Ahmedabad was 304, while that of
Faridabad was 341. Delhi on the
other had an AQI score of 259 and
was rated "poor" by CPCB. Since the
last two days the CPCB has been
releasing a daily air quality bulletin
for 11 cities across the country.
The AQI is decided on ambient
concentration values of air
pollutants and their likely health
impacts which are commonly called
health break points. The pollution
parameters whose concentration is
measured in ambient air include
particulate matter that are of size
2.5 microns (PM 2.5), PM 10,
nitrogen dioxide, sulphur dioxide,
carbon monoxide, ozone, ammonia
and lead. The pollution parameter is
measured over a period of 24 hours
and the data is revealed by the
CPCB the following day.