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Air Quality Analysis Systems

Case Studies

Sloan Foundation and iCHEAR, Denmark

Human Influence on Indoor Air

iCHEAR (Indoor Chemical Human Emissions and Reactivity) is a Sloan-funded collaborative research project designed to examine the role of humans and human emissions on indoor air chemistry. It is led by research group leader Jonathan Williams (Max Planck Institute for Chemistry) in collaboration with Pawel Wargocki and Gabriel Bekö (Department of Civil Engineering, Technical University of Denmark-DTU) at the International Centre for Indoor Environment and Energy (ICIEE). iCHEAR investigates exhaled, dermally emitted and overall human emissions in carefully controlled stainless steel twin climate chambers (see photo above) under different conditions of clothing, temperature, relative humidity and ozone and their impact on OH reactivity.

The Picarro G2103 analyzer provides real-time measurements of ammonia emissions (red line) from the volunteers under well-characterized conditions. Although ammonia is emitted by humans and has a large impact on indoor acid/base chemistry, its emission from human occupants have been poorly characterized. These measurements enable researchers to determine the rate at which the volunteers emit ammonia under different temperature and relative humidity conditions. They also enable ammonia emissions from breath to be separated from those in dermal off-gassing. Early results show that ammonia concentrations are substantially higher at the higher temperature condition and more exposed skin (higher emission on the right-side plot, when compared to the plot on the left).

Learn more about the Sloan Foundation program and iCHEAR at: https://indoorchem.org/projects/indoor-chemical-human-emissions-and-reactivity-ichear/human-emissions-and-reactivity-ichear/

ILVO, Belgi

Emissions From Livestock Barns

Agricultural activities and processes emit greenhouse gases like carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O), as well as ammonia (NH3). While greenhouse gas emissions affect the global climate, ammonia is a toxic pollutant that affects human health and the environment on a regional level, e.g. by threatening biodiversity. The agricultural sector is the highest ammonia emitter and most of the emissions come from fertilizer use, decomposition of biological material and animal excretions. In many regions, the level of ammonia emissions is increasing further, and therefore, there is a general interest in reducing emissions in order to meet environmental regulations.

Researchers Shaojie Zhuang and Philippe van Overbeke from the Flemish Research Institute for Agriculture, Fisheries and Food (ILVO) in Belgium used the Picarro G2508 multi-species gas analyzer when testing for ammonia and greenhouse gas concentration measurements in a dairy and a pig barn. The focus of the study was to determine how several instruments would perform when measuring challenging, high adsorption gases such as ammonia. For this study, parts of the internal sample handling line of the Picarro G2508 were replaced with Teflon instead of stainless-steel, to improve the response time. The upgraded Picarro G2508 showed very good accuracy for ammonia and no evident drift over the two-month field test. The performance of the G2508 for ammonia measurements was compared to an open-path tunable diode laser gas analyzer (OPL) as well as a closed-path quantum cascade laser (QCL), see figures below.

The Picarro G2508 was able to accurately measure ammonia concentrations along with CO2, CH4 and N2O concentrations. The ammonia concentration range and the response time of the analyzer are suitable for a variety of applications in agricultural science.

Learn more about this research project at ILVO:https://pure.ilvo.be/portal/en/

Airlabs, UK

Air Quality in Vehicle Cabins

Air quality in urban areas is often poor due to a range of pollutants emitted by traffic and industrial point sources. The closer one is to the emission source, like traffic, the higher the exposure level. This also applies to car drivers themselves since the emissions of the nearby cars will also enter the vehicle cabins. The London-based clean air technology company Airlabs set its goal to improve the air quality in cities and to provide solutions for citizens to minimize exposure they encounter throughout the day. One of their consumer products is a portable air cleaner, the airbubbl, that removes particulate matter, NO2 and other pollutants from air. Knowing that elevated H2CO concentrations can cause irritations of the respiratory tract, Airlabs used the Picarro G2307 analyzer to verify and improve the H2CO removal rates of the airbubbl. Inside vehicles, formaldehyde levels can be elevated due to the intake of polluted air from outside or due to outgassing of fabrics inside the vehicle. Continuous, real-time operation of the analyzer, along with its stability and rapid response rates were essential to the success of these measurements.

Learn more about Airlabs and Airbubbl at:www.airlabs.com

Korus-AQ, South Korea

Secondary Aerosol Formation

The formation and health impacts of secondary aerosols is an important scientific and socio-political subject in the Asia-Pacific region. Picarro analyzers are being used to support research and monitoring initiatives whose objective is to detect and quantify emissions from a variety of urban and rural sources. The Korean National Institute of Environmental Research (NIER) maintains a network of Picarro analyzers (HF, HCl, NH3 and others) that are being used as part of NASA’s International Cooperative Air Quality Study known as KORUS-AQ. One potential source of poorly quantified NH3 emissions are local livestock farms. Although a marked increase in NH3 emissions near these sites could lead to a rise in PM2.5, more measurements are required to quantify its effects on regional air quality.

Learn more about the KORUS-AQ and NIER at: https://espo.nasa.gov/korus-aq/content/KORUS-AQ