Articles | Volume 16, issue 19
https://doi.org/10.5194/amt-16-4357-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/amt-16-4357-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
05 Oct 2023
Research article |
| 05 Oct 2023
| 05 Oct 2023
Seasonally optimized calibrations improve low-cost sensor performance: long-term field evaluation of PurpleAir sensors in urban and rural India
Mark Joseph Campmier
Department of Civil and Environmental Engineering, University of California, Berkeley, Berkeley, CA 94720, USA
Jonathan Gingrich
Department of Engineering, Dordt University, Sioux Center, IA 51250, USA
Saumya Singh
Department of Civil and Environmental Engineering, University of California, Berkeley, Berkeley, CA 94720, USA
Nisar Baig
Department of Civil Engineering, Indian Institute of Technology Delhi, New Delhi, Delhi 110016, India
Shahzad Gani
Centre for Atmospheric Sciences, Indian Institute of Technology Delhi, New Delhi, Delhi 110016, India
Institute for Atmospheric and Earth System Research/Physics, University of Helsinki, Helsinki 00100, Finland
Adithi Upadhya
ILK Labs, Benson Town, Bengaluru 560046, India
Pratyush Agrawal
Center for Study of Science, Technology and Policy, Bengaluru 560094, India
Meenakshi Kushwaha
ILK Labs, Benson Town, Bengaluru 560046, India
Harsh Raj Mishra
Indo-Gangetic Plains Centre for Air Research and Education (IGP-CARE), Hamirpur 210301, India
Ajay Pillarisetti
School of Public Health, University of California, Berkeley, Berkeley, CA 94720, USA
Sreekanth Vakacherla
Center for Study of Science, Technology and Policy, Bengaluru 560094, India
Ravi Kant Pathak
Indo-Gangetic Plains Centre for Air Research and Education (IGP-CARE), Hamirpur 210301, India
Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg, Sweden
Joshua S. Apte
CORRESPONDING AUTHOR
Department of Civil and Environmental Engineering, University of California, Berkeley, Berkeley, CA 94720, USA
School of Public Health, University of California, Berkeley, Berkeley, CA 94720, USA
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Short summary
We studied a low-cost air pollution sensor called PurpleAir PA-II in three different locations in India (Delhi, Hamirpur, and Bangalore) to characterize its performance. We compared its signal to more expensive reference sensors and found that the PurpleAir sensor was precise but inaccurate without calibration. We created a custom calibration equation for each location, which improved the accuracy of the PurpleAir sensor, and found that calibrations should be adjusted for different seasons.
We studied a low-cost air pollution sensor called PurpleAir PA-II in three different locations...
