Demonstration of Near-Referencemonitoring of air pollution using low cost compact air quality monitoring
stations in Delhi, India
Paul R PickeringCAA Better Air Quality Conference
Busan, South Korea29 August 2016
Acknowledgements
Paul R Pickering Nevco Engineers Pvt Ltd
Nick Reid Akansh Gupta
Dr Geoff Henshaw
TUV India Pvt Ltd Central Pollution Control Board
L N Bharti Dr D Saha
Asia’s air monitoring challenge
• Survey of 69 Asian cities in 17 countries found
70% have insufficient stations, not ideally located
and monitor few pollutants (ADB 2014)
• Air Quality Index representative of a city should
consider air quality data from different
microenvironments (IITM 2016)
• Sustainability of air quality monitoring networks is
a major challenge with budget constraints
More monitoring needed for India’s air pollution control policies
Study shows poor air quality reduces life expectancy
of Indians by 3.4 years and Delhi residents 6.3 years
(Ghude SD et al 2016)
Near-Reference instruments offer a realistic solution
• Strong statistical correlation to reference methods
• Calibration traceable to Standard Reference
Materials for high data quality objectives
• Reliably measure criteria air pollutants to
international standards e.g. EPA, EU, WHO
• Complement existing air pollution networks for
higher density, real-time data
• Easy to deploy for localised monitoring events
• Less expensive to own and operate
AQM 65 CAQMS PC, phone, tablet
Cloud serverModem
Low cost compact air quality monitoring station (CAQMS)
Secure real-time air data• ISO 27001 data centres
• Data access via secure website
• 256-bit SSL encryption
• User defined passwords
Central Pollution Control Board trials AQM 65 CAQMS in Delhi
Aeroqual AQM 65 CAQMS installed at the CPCB site
by Nevco Engineers and calibrated by TUV India
Purpose of the CPCB trial
• AQM 65 configured to deliver
Near-Reference data for O3,
NO2, CO, SO2 and PM2.5
• August 2015 to January 2016
• Demonstrate accuracy and reliability of CAQMS
• Evaluate fitness for purpose under challenging
environmental conditions
• Correlate with local reference air quality data
High data validity recorded for criteria pollutants
CO NO2 O3 SO2 PM2.5
Hourly
Number of
values3406 3686 3133 3684 3678
% Valid data 96.56 96.92 96.38 96.87 96.71
Daily
Number of
values152 159 155 159 159
% Valid data 95.0 99.4 96.9 99.4 99.4
The instrument recorded over 90% data validity for
hourly data and over 95% for daily data
Accurate and reliable in ambient conditions
CO NO2 O3 SO2 PM2.5
Hourly
Maximum 10.212 0.188 0.222 0.849 1233
Minimum 0.000 0.000 0.000 0.000 0.643
Average 1.572 0.023 0.037 0.022 191
SD 1.343 0.021 0.025 0.040 186
Daily
Maximum 6.240 0.050 0.100 0.140 713
Minimum 0.060 0.000 0.000 0.000 15
Average 1.560 0.020 0.040 0.020 190
SD 1.120 0.010 0.020 0.020 159
The instrument demonstrated excellent response
to ambient conditions and high data recovery
Local events captured in hourly average data
Good ability to measure high PM2.5 (>1000 µg m-3)
Seasonal variations captured in daily average data
Summer to winter transition shows higher PM, CO,
NO2 and SO2 while ozone levels declined
Hourly concentrations captured during Diwali period
Elevated PM2.5 and SO2 levels were approx. four
times higher than either side of Diwali
Diurnal and hourly pollutant patterns collected
Site pollutant behaviour was dominated by morning
and evening traffic and urban emissions
PM2.5 comparison to DPCC Reference Data
Good correlation with DPCC site 5 km to East
DPCC trials monitoring during the odd-even vehicle campaign
Delhi Pollution Control Committee uses AQM 65
for supplementary monitoring in January 2016
Hourly average concentrations during odd-even vehicle trial
Data from the AQM 65 at the CPCB site for first
week of the Delhi odd-even trial
Key conclusions
• The CAQMS demonstrated excellent response to
ambient conditions and high data recovery
• High pollutant concentrations during Diwali were
captured and documented
• Diurnal pollutant variations collected and analysed
• PM2.5 channel correlated well with DPCC station
5km E indicating high regional PM contributions
• CPCB concludes AQM 65 ‘works consistently
including data generation up to 90% and to our
satisfaction’
Letter from CBCB India
“The instrument
(AQM 65) was
found to work
consistently
including data
generation up to
90% and to our
satisfaction.”
D Saha, Scientist ‘E’,
In-charge Air Lab,
CPCB
Thank you for your attention