Title: Assessments and Application of Low-Cost Sensors to Study Indoor Air Quality in Layer Facilities
Authors: Rowshon Afroz, Xinyang GUO, Chu-Wen Cheng Sohaib Omar, Valerie Carney, Martin Zuidhof, Ran Zhao
ABOUT
Intensive poultry farming deals with flocks of several thousand birds gathered in one or several buildings, and it can be a significant source of air contamination. Thus, worries regarding the emissions of contaminants such as aerosolized particles or dust, and various gases from intensive poultry facilities are growing, especially concerning their impact on the environment and health. Dust can originate from various sources, including floor bedding, feed, feathers, excreta, dander, bird’s skin, and microorganisms. Given that, monitoring and source apportionment of dust are crucial for creating appropriate regulations that protect the health of birds and producers. Therefore, it is essential to collect real-time, spatiotemporally-resolved data for a complete understanding of PM characterization and to accurately assess exposure for both humans and animals. Unfortunately, air monitoring instruments available on the market are generally expensive (costs >$20,000 CAD each) and unable to provide sufficient coverage of air quality in dusty barn environments. In this regard, this study was conducted to implement and assess the field performance of a compact, custom built IoT low-cost air quality sensor (LCS -$180 CAD) network in an indoor table egg farm in Canada. The sensor-enabled real-time monitoring of PM2.5, PM10, and CO2 concentrations, RH, and temperature. The work also aimed to characterize factors that affect these parameters in the farm. The findings of this study will both showcase a novel technique and provide scientific insights into environmental conditions in commercial poultry facilities.
APPROACH
The LCS performance was assessed in the Poultry Research Centre (PRC) farm with 70 ± 7 birds housed in floor pens. At this stage, three LCS were set up to assess their performance from November 2021 to September 2022. Then, we monitored indoor air quality (IAQ) in a commercial layer farm from November 2022 to April 2023, where six LCS were deployed. This freerun, organic egg farm had a capacity of approximately 8,000 laying hens in a single barn. A sensor was installed in the preparation room of the farm to observe the correlation and concentration of PM levels because workers do not wear personal protection equipment (PPE) in there as they do inside the barn. Inside the barn, the sensors were deployed at different heights (0.6 and 2.7 meters) and locations, including along the front of the cage and on the wall. The LCS were deployed continuously at the PRC and commercial farm. To ensure their accuracy and performance, a reference instrument was colocated with the LCS and checked during every farm visit made by the research team.
ANALYSIS OF RESULTS
Our research found that the concentrations of both PM10 and PM2.5 followed a diurnal pattern. Both PM10 and PM2.5 concentrations were low at nighttime (when the light was off) but spiked during the daytime. This suggests that PM emissions were significantly impacted by the activity level of chickens. The mean hourly average of PM10 and PM2.5 concentrations for sensors during daytime were 5.5 × 104 ± 2.2 × 104 and 6.3 × 103 ± 2.3 × 103 µg/m3, respectively, while concentrations during nighttime were 4.9 × 103 ± 2.4 × 103 and 750 ± 80 µg/m3 for PM10 and PM2.5, respectively. Higher PM levels during the daytime, unfortunately, mean that farm workers’ respiratory health is at considerable risk. Additionally, the study found a positive correlation between PM2.5 and PM10 levels inside the barn and in the preparation room, indicating that the dust infiltrated from the barn to its outside through openings, elevating the PM levels. The study suggests that both PM10 (91 ± 103 µg/m3) and PM2.5 concentrations (33 ± 15 µg/m3) may exceed recommended daily exposure limits, underscoring the importance of considering the health impacts over time. Given that producers work there without wearing PPE, the concentration we recorded can be a health concern even though the preparation room concentrations were much lower than the barn concentration.
APPLICATION
This study demonstrated the development and application of low-cost air quality sensors (LCS) in poultry facilities. The sensors ($180 CAD ea.) had the capacity to measure PM2.5, PM10, CO2, temperature, and RH, which are all considered key IAQ parameters. This study reveals that the laying house had elevated levels of PM and CO2. A strong correlation was also found between the indoor concentration of PM, CO2, and relative humidity. The concentration levels and trends of both pollutants were influenced by factors such as chicken activity, light regime, ventilation rate, and outdoor temperature. In addition, the study also observed the impact of housing pollutants on areas where producers work regularly but not with PPE. Overall, the results suggest that the LCS could be a valuable tool for monitoring IAQ in poultry facilities.
http://dx.doi.org/10.2139/ssrn.4727260
Thania joined PIP as the PIP Extension technician in 2021.
