Session 3: Indoor Air Quality, Exposure & Health, Youth Education & Development

VFS Session 1

Event Date

Virtually through Zoom

Session moderated by Ajith Kaduwela, California Air Resources Board, and Katie George, California Air Resources Board

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Using a Particle Sensor Network to Characterize Indoor and Outdoor Air Quality of Buildings in Areas Prone to Wildfires

Presented by: Heidi Vreeland, US EPA Office of Research and Development

Summary: When wildfire events increase outdoor particulate matter concentrations to unsafe levels, a common recommendation for mitigating smoke exposure is to spend time indoors. However, effectively reducing smoke exposure and maintaining clean air indoors depends on a variety of building characteristics and occupant behavioral factors. To gain insights into the indoor/outdoor relationships of PM2.5 across buildings, this study utilizes low-cost sensors (PurpleAir PA-II-SD) to characterize indoor and outdoor PM2.5 at public and commercial buildings in two locations impacted by wildfire events in recent years: Missoula, Montana and Hoopa, California. Sensors were stationed inside and outside of 18 buildings across Missoula during summer 2019 (July–Sept) to coincide with peak fire season, and 11 buildings across Hoopa during winter (Nov 2019 – Feb 2020) when woodstove heating dominates outdoor emissions. Prior to evaluating indoor reductions, criteria were developed to identify indoor-generated sources. Preliminary results suggest that indoor reductions ranged from 6% to 44% (26±11%) in Missoula, and 19% to 69% (51±16%) in Hoopa. The smaller reductions in Missoula are largely attributed to frequent door openings for ventilation during summer. In Missoula, indoor reductions were similar during smoke-impacted and typical (non-smoke) periods indicating that measurements taken outside of fire season are informative and may be useful for improving smoke preparedness. Although the only smoke events that occurred in Missoula during summer 2019 were moderate and associated with prescribed burns, this work provides valuable insights into the variance among indoor/outdoor PM2.5. This work also demonstrates the utility of low-cost sensor networks for residents and public health agencies to better understand where clean indoor spaces exist and, potentially, to offer guidance on reducing indoor concentrations before smoke events occur.

Air quality monitoring and comparison in olympic stadiums of five continents using low cost sensors

Presented by: Edurne Ibarrola, Kunak Technologies

Summary: World Athletics started in 2018 to create a real-time air quality network with global coverage to help athletes choose the best times to train and compete and to help organizers to protect the health of athletes, understanding air quality impacts on people’s life quality. The objectives were to (1) monitor environmental conditions in Olympic stadiums and marathons, (2) study the air pollution impact in athlete’s health and performance, (3) raise awareness on air quality issues and make better decisions, (4) offer an added value to athletic competitions in terms of sustainability, increased protection of the health of participants and social awareness.

Kunak-Air 10 is provided with CO, NO2, NO, O3, NOx, PM10, PM2.5, PM1, and meteorological sensors. Five different K-Air 10 were set up in Olympic stadiums: Addis Ababa (Ethiopia), Mexico DF, Monaco, Sydney and Yokohama. In this context, the temporal patterns for gases and particles were studied during a period of one year (December 2018-November 2019). For gaseous pollutants, higher concentrations of O3 appear in Monaco and Yokohama, while the highest concentrations of NO2, NO and NOx appear in Addis Ababa and Mexico DF. Yokohama and Monaco stadiums are notable for the low pollutant concentrations reported (except for O3). The impact of traffic emissions is detectable in all the stadiums during the mornings, whereas distinct evening traffic peaks are observed in some of them. The highest particle concentrations were recorded at the Addis Ababa stadium and Mexico DF.

The main conclusions are: all the stadiums appear to be impacted by vehicular traffic emissions; the highest air pollutant concentrations were recorded in Addis Ababa and in Mexico DF; the daily time patterns of air pollutants provided useful information to identify optimal periods for training or competition in each stadium; and periods and days of the week which were most advisable for outdoor sports activities in each of the stadiums were identified.

Follow Up Q&A

  • When were the Addis Ababa measurements taken? (Month, year?)
    • The measurements were taken during 3 months, from November 2018 until January 2019- Nowadays, there is a new Kunak device operating in Nairobi since August 2020.
  • Where were the sensors located within the stadia? - Amy Heidner
    • The sensors usually are deployed close to the training tracks. For instance the Mexico unit was installed in the Mexican Olympic Committee training venue, at approximately 3 meter above ground level and attached to a pole. 
  • Where were sensors placed in Marakesh and what is the reason of high NOx/NO2 levels if in theory running event should result low traffic activities in the city ? - Adyl Anvarov
  • how many sensors per stadium?  (Multiples  are needed to observe effects of wind direction, etc.) - Amy Heidner
    • Monaco stadium was the only one with two Kunak devic, in the case for the other stadiums, only one device was deployed. However, all of the devices integrate an anemometer to observe the effects of wind direction, and speed, etc. Thus, it is possible to analyze the source of the different pollutants.
  • Edurne, is there an option to reschedule the run or training periods depending on the predicted wind direction, or generally predicted pollution levels? - Dmitri Chubarov
    • After more than one year of data, we have detected the best time period to organize a sport event in a stadium. One of the objectives of the study is to help organizers to make better decisions and with the data provided it is possible.


Community-driven open-data on Pakistan’s air pollution problem

Presented by: Abid Omar, Pakistan Air Quality Initiative

Summary: Pakistan has an air quality data problem with little to no monitoring across the country. Community-driven air quality monitoring has been instrumental in filling the air quality data gap in Pakistan, and in creating a grassroots citizen’s movement advocating for clean air. Real-time data from this community network has put a magnifying glass on air pollution, where citizens can react to their local air pollution, evaluate impact of emission-reduction policies, and ultimately providing the impetus for a cleaner environment.

This paper presents Pakistan as a case study of a typical low-income country, similar to other developing countries across South Asia and Africa, lacking reference-standard monitoring equipment, or the technical capacity to manage them. Pakistan’s community-based nationwide network of low-cost real-time air quality monitors has helped fill the data gap in Pakistan and has been instrumental in many ways, by engaging the community and corporate citizens in participatory monitoring, by creating a network of ambassadors for air quality awareness, and finally by providing the baseline data for the government to initiate reference-standard monitoring. The impact from this community monitoring network has been tremendous in kick-starting awareness and furthering monitoring in one of the most air-polluted regions of the world. 

Learnings from this initiative are shared to enable other communities, cities and countries to harness a similar network of low-cost monitors to kick-start positive environmental change in their region, and how to engage and develop a community of citizen scientists to deploy, maintain and manage air quality sensors in a decentralized network.

Follow Up Q&A

  • What is the price difference between AirVisual and Purple Air? - Ajith Kaduwela
    • Both AirVisual and Purple Air are priced at around 300 USD.
  • How often do you replace or recalibrate PM sensors in Pakistan due to the heavy pollution? - Sotirios Papathanasiou
    • ​​​​​​​We have been “validating” the sensors by comparing them with 2 “reference (unused) monitors. Our process is to place them in a room, add smoke to measure a peak value, and then run a portable air cleaner (HEPA filter) to measure the low value. Then we compare trends between the reference and the monitor(s) under validation. It’s a simple yet effective methodology that helps weed out any anomalous sensors. We are surprised that we find most of the sensors (90%) have not required replacement in the 4 years of running them.
  • ​​​​​​​How do you perform quality assurance for this sensor network in Lahore, Pakistan? - Abdul Samad
    • See above regarding validation. We are very reliant on AirVisual’s remote “calibration and validation” done in the cloud…. They compare data amongst other outdoor sensors in the area and also against satellite data. They also remove any data anomalies, and sensors are automatically taken offline if they are consistently reporting anomalies. Some of these are manually verified, e.g. if one particular monitor is consistently show very different values (from other monitors AND also from historical data from the dame monitor), we try to identify the root cause before putting it back online to the public: e.g. has the monitor location been moved, or in one case we found that it was too close to a BBQ grill.
  • No doubt that Lahore is highly polluted.  Can the differences be due to different measurement techniques? - Ajith Kaduwela
    • ​​​​​​​All the monitoring shows high levels of pollution: whether we look at remote sensing satellite data, or reference-standard data by the US Consulates, or the data coming from our low-cost monitors, or the data reported by the government’s monitoring systems.
  • Where is the majority of pollution coming from in Pakistan? Is it mainly from industries (how regulated are emissions from corporations in Pakistan?, or traffic/mobile sources, etc? - Allison Langone
    • Primarily from transportation due to the poor fuel (diesel and petrol) quality available here. The fuel standards have been antiquated. Since June 2020 approximately 50% of imported fuel will meet Euro V standards, but we have a long way to go before local refineries upgrade. Other emissions are industrial, urban waste, and agricultural emissions. Looking at media reports, most put the blame on crop-burning and brick-kilns, but we have some reports that show that those are relatively smaller contributors. 
  • Whats the estimated margin  of error for airvisual sensors, considering most of airvisual sensors are located in gasoline stations with Roofs, roofs may interfere with actual PM concentration - Jundy Del Socorro
    • AirVisual sensors in Pakistan are mostly location in residential or commercial (office) areas. I believe you are thinking of the deployment in Philippines which is deployed through a gas station network. Our R2 value as compared to the US Consulate monitor is 0.92. Send me an email, I'll share the details.
  • Are there any studies on HVAC forced air systems and the recirculation of particulates spreading. Is forced air used in Pakistan and the European Nations as much as the US - Terry Ellis
    • ​​​​​​​HVAC is very unusual in Pakistan.
  • Are you seeing support/funding for your project from private Pakistan based organisations wanting to develop their own understanding of domestic air quality? - David Johnson
    • ​​​​​​​Very limited. A few companies have bought monitors from us and deployed them. We have an equal number of community funded monitors and company funded monitors.
  • Is there is any data on the morbidity and mortality of PM pollution in urban areas?  Lot of studies for Delhi and Beijing indicate significant suffering. - Krishna Naishadham
    • No direct studies. We are trying to get the medical community and researchers to look into it. However, we can refer to the indirect study: University of Chicago's Air Quality Life Index which shows a life expectancy reduction of 2-6 years (based on city).
  • Are there future plans on placing more monitors around Lahore? what type of monitors are you currently using and are there any alternatives on the type of sensors maybe a cheaper option? - Naufal Calvin
    • When it comes to larger deployments, the bigger cost is of managing the deployment itself. Such as poor access to reliable electricity and internet. A cheaper sensor might reduce the cost, but it does help to have scale, which the AirVisual and PurpleAir have. If we are to "reinvent the wheel" with our own low-cost sensor, our bigger challenge will be in validation and calibration (which also costs a lot).
    • Future plans: trying to solicit funds for more monitors through international partnerships and collaborations. Would love to expand the network by 10X. Unfortunately in Pakistan one does not have mechanisms such as Paypal where one can solicit funds.​​​​​​​


Youth Education:  Measurement of Indoor Air Quality Impacts of Nearby Wildfires using Low-Cost Air Sensors.

Presented byTara Lee, Minju O’Rourke, & Sean Morris, of Albany High School, Albany Unified School District and Ajith Kaduwela, Air Quality Research Center, UC Davis

Summary: The Air Quality Club at the Albany High School was established at 2017 and currently conducts air quality measurements (mainly indoor) using low-cost sensor packages.  Due to COVID-19 crisis, the school was closed for several months and the sensor packages were moved into the homes of students and teachers to assess the air quality impacts of COVID-19 lockdown.  During this investigation, three major lightning-induced wildfire complexes started in the Bay Area on August 16-19, 2000.  Albany was affected by these fires depending on the wind direction.  In this presentation, we will first describe the Club activities since the previous AISC presentation in 2018.  We will then compare and contrast the indoor impacts of these nearby wildfires with those of the 2018 distant Camp Fire (findings of Camp Fire impacts are now published in the Journal of Air & Waste Management Association).  We will conclude the presentation with future plans for the Club.

Engaging School Communities in Air Senors

Presented by: Aubrey Burgess, Denver Department of Public Health and Environment & Yvonne Cappel-Vickery, Denver Department of Public Health & Environment

Summary: The City and County of Denver’s Love My Air program is creating a citywide air quality (AQ) monitoring network to provide real-time AQ data—utilizing low-cost cutting-edge air pollution sensor technology to make it useful for widescale deployment and replicability. Love My Air aims to empower school communities to reduce air pollution and limit exposure through behavior change, advocacy, and community engagement. By 2021, 40 Denver Public Schools (DPS) will have sensors and dashboards that relay hyper-local, real-time data. The data dashboards are visible via a large TV display inside each school and at School communities (23 currently) use this data to learn AQ basics, how their behaviors impact local AQ, and how it impacts their health. 

Love My Air Denver is exploring innovative opportunities to engage school communities. For example, AQ curricula are paired with hand-held sensors allowing students to conduct their own citizen science projects. The curriculum has been redesigned to include virtual labs and at-home activities for the new virtual school year. Students can put their knowledge to the test with community-wide science projects and friendly competitions. Love My Air Denver is also in the process of developing a phone app that would allow for interactive access to AQ forecasts and data, tips for reducing exposure, and other educational tools. Students also have the opportunity to engage in several art projects, including working with a local artist to paint their school’s sensor and designing customized anti-idling campaign signage. 

Another core value of Love My Air Denver is to utilize community members at experts. Parents, teachers, nurses, principals, and students have been involved in the development process from designing the dashboards to developing curricula. The vision is to share best practices and lessons learned throughout this process to make this program replicable by other municipalities.

Denver Department of Public Health and Environment Presentation PDF

The GO3 Project and AQTreks: A decade of air pollution monitoring with students and the public

Presented by: Jessa Ellenburg, 2B Technologies

Summary: Over the past decade, new and emerging technologies in air pollution instrumentation have made it possible to involve students and citizen scientists in air pollution monitoring. Similarly, advances in data communication and transmission have made it increasingly easy to share and display data. Two educational programs, the Global Ozone (GO3) Project and AQTreks, have used these advances to get air pollution monitors into the hands of thousands of students around the world and to automate data sharing. These educational projects began in 2009 with the GO3 Project, a stationary ground level ozone monitoring project. In the GO3 Project, students and teachers at more than 100 schools from around the world installed ozone and weather monitoring stations at their schools with automatic uploading of their data, resulting in more than 12 million ozone measurements. Over the years, new technologies became available for students to expand their measurements from stationary to mobile platforms. Since 2016, the AQTreks educational program has been developed concurrently with the Personal Air Monitor (PAM), a mobile sensor suite paired with a smartphone app. Complimenting the technology are online curricula and resources for students and citizens to learn about air pollution and climate change. In these projects, a focus on data quality and the careful selection of monitoring technologies have resulted in scientific use of the student-collected data, including their incorporation in several research campaigns that have furthered understanding of ground-level ozone formation. My talk will cover general information about our path and lessons learned from our air pollution monitoring programs. I will address the various benefits and disadvantages of stationary vs. mobile educational programs, including the aspects students seem to be most interested in, the scientific value of the data, etc. I will tailor my talk to the audience, focusing on the interests of those in attendance.

2B Technologies Presentation PDF

Follow Up Q&A

  • Which FEM or near-FEM are you using in the calibration system (AQsync) for PM2.5? - Michael Flagg
    • Answer: Met One Instruments, Model 9722
  • How much is the Personal Air Monitor (PAM)? (roughly) - Arezoo khodayari
    • Approximately $1,500.  We are currently creating a much smaller PM sensor package that will be much less expensive if you are looking for PM only.
  • What is the estimated period that a sensor needs to be recalibrated? And if a sensor for example ozone sensor is giving negative value though is within the range from other co-located sensors measurement, what likely may be the cause of it in the instrumentation? - Najib Yusuf
    • As a rule of thumb, one is looking at a 1-year period between re-calibration OR replacement with a calibrated sensor. Likely, for larger deployments, the cost of replacement will be less than or equal to calibration.
  • Can these devices be used in an actual indoor environment? - Terry Ellis
    • ​​​​​​​​​​​​​​​​​​​​Yes, you can use ANY air quality monitor indoor or outdoor. Outdoor deployment requires protection from weather conditions which still allowing air flow through the sensor. Also, our community-network has to ensure that the monitors are actually outdoors, and not taken indoors. The AirVisual cloud-based and automated process helps detects that.