Unique Approach
The Open Air outdoor monitor has been designed with a unique approach:
- Open Source Hardware and Software. The monitor is fully open source including drawings, 3D files, schematics and firmware code. It is licensed under Creative Commons CC BY-SA 4.0. All technical documentation can be accessed here.
- Affordable. The monitor has been designed from the ground up to offer an affordable option for countries, regions and NGOs with limited financial possibilities.
- Trusted Design. Using well tested and reliable sensor modules as well as ongoing extensive co-location testing, the Open Air monitors strengths and weaknesses are and will be well understood.
- Full Transparency. We do not only publish the design of the monitor but will also publish all co-location data, results and compensation algorithms.
- Extendable. With its open source design, the monitor can be easily extended with additional sensor modules or connectivity options.
- Local Capacity Development. We actively support knowledge transfer to local entities that want to assemble and value-add to the Open Air monitor.
- Availability. The monitor is available in our online shop but due to its fully open design, can also be built with components sourced elsewhere.
Scientific Partners
Our open hardware approach is of great interest to the scientific community as it allows easy addition and changes to the hardware and software of the monitors to adjust them to meet exact research objectives. We are thankful to our scientific partners to co-locate our air quality monitors with their scientific instruments and are working together to test the devices in different environments and develop compensation algorithms to closely achieve reference grade data quality.
Current Co-Location Sites
We are currently testing the Open Air outdoor monitor on more than 20 sites around the globe.
Open Air Monitor Co-Location Sites
Co-Location Institution |
City, Country |
Deployment since |
University of Cambridge |
Cambridge, UK |
February 2023 |
National Astronomical Research Institute Thailand |
Chiang Mai, Thailand |
February 2023 |
North West University / CAP |
Vanderbijlpark near Johannesburg, South Africa |
March 2023 |
University of Washington |
Guatemala City, Guatemala |
April 2023 |
Northwest Clean Air Agency |
Anacortes, WA, United States |
May 2023 |
Northwest Clean Air Agency |
Bellingham, WA, United States |
May 2023 |
Imperial College |
Marylebone Road, London, UK |
May 2023 |
Imperial College |
Honor Oak Park, London, UK |
May 2023 |
Environment and Climate Change Canada |
Halifax, Canada |
June 2023 |
Environment and Climate Change Canada |
New Brunswick, Canada |
June 2023 |
Environment and Climate Change Canada |
Edminton, Canada |
June 2023 |
University of Environment and Sustainable Development Ghana |
Physics Department, University of Ghana, Accra, Ghana |
June 2023 |
FHI 360 |
Kathmandu, Nepal |
July 2023 |
Universidad Nacional Autonoma de Mexico |
Mexico City, Mexico |
August 2023 |
Arizona State University |
West Campus, Phoenix, Arizona, United States |
August 2023 |
University of California Merced / SEEN Team |
Merced, California, United States |
August 2023 |
Center for Air Quality, Climate and Health of the Sri Ramachandra Institute of Higher Education and Research |
Chennai, India |
September 2023 |
Communities Against Air Pollution |
Richards Bay, South Africa |
September 2023 |
Columbia University Lamont-Doherty Earth Observatory |
New York, USA |
September 2023 |
AFRI-SET - Air Quality Sensor Evaluation and Training Centre for West Africa |
Accra, Ghana |
September 2023 |
Clean Air Asia |
Manila, Philippines |
September 2023 |
Indian Institute of Technology |
Delhi, India |
Expected September 2023 |
University of Birmingham |
Birmingham, UK |
Expected October 2023 |
Stockholm Environment Institute |
Nairobi, Kenya |
Expected October 2023 |
Stockholm Environment Institute |
York, UK |
Expected October 2023 |
Unparalleled Global Data Set
By following a common research approach with all these co-location tests, we are building the first global data set of low-cost monitor testing worldwide. This allows us to understand the exact behaviour of the monitor in various environments in regards to climate and particle compositions. All the data and the compensation algorithms that we will develop will be published and allows organizations and citizen scientists a high level of accuracy.
Co-location with certified instruments
The Open Air monitors are closely co-located with certified reference instruments which are regarded as the golden standard in air quality monitoring. By comparing the measurements from the Open Air monitor with the reference measurements, we can determine the measurement performance of the monitors.
Impact of environmental conditions
The monitors are tested at various geographic locations with diverse climatic conditions and pollution levels. This way, the impact of the environmental conditions on the monitoring performance can be systematically studied.
A large collaborative network
Currently, more then 20 international research organisations, NGOs and action groups are voluntarily supporting this co-location project, for example by providing reference instrumentation and air quality expertise. More partners are likely to join. Thank you!
Open data to increase awareness
All AirGradient data collected during this project will be shared with the public*. This way we want to improve the public access to continuous air pollution data and increase public air quality awareness.
*Most reference data from our partners can already be found online.
Performance criteria
To understand the measurement performance as detailed as possible, we will evaluate the monitor’s reproducibility,
accuracy, precision, limit of detection and long-term stability. Furthermore, we will investigate if / how these performance
parameters differ at very high and very low concentrations, through meteorological factors (e.g. extreme temperatures) or through interferences with other pollutants. We also plan to examine the impact of the particle composition and size distribution on the Open Air PM2.5 measurements.
Join Us!
If you are a research institution or NGO and interested in joining our co-location program, please contact us.
The more reliable data we can generate in different environmental conditions, the better we understand the strengths and weaknesses of the monitor and can develop accurate compensation algorithms.