Abstract: The detrimental effects of poor air quality on human health, ecosystems, and the economy make it a very concerning component in environmental deterioration. Although pollution monitoring technologies have made significant progress, there exists a distinct disparity in the availability of air pollution data. As to the recent assessment on air quality in Colombia, regulatory grade monitoring is only available in 19 out of the country’s 32 departments and 77 municipalities (IDEAM, 2021). Therefore, additional efforts are required to establish air quality monitoring stations. The global adoption of low-cost sensors (LCS) is rapidly increasing as a means to address these information deficiencies. These devices are employed for preliminary monitoring, pinpointing areas of concern and sources of emissions, facilitating informed decision-making by individuals to safeguard their well-being, and fostering active citizen engagement that impacts public policy. Three distinct projects utilizing LCS have been executed in Bogotá (Colombia) and its surrounding metropolitan region since 2020. The “Aires Nuevos para la Primera Infancia” initiative, funded by the “Horizonte Ciudadano” Foundation of Chile, facilitated the implementation of affordable sensors in public kindergartens across various Latin American cities. In Bogotá, the project was executed by the Universidad Nacional de Colombia with the backing of the local government. Over the course of one year, six AirVisual Pro monitors were utilized to measure Particulate Matter PM1, PM2.5, and PM10. The collected data was then compared to the data obtained from the nearest air quality stations that adhere to regulatory standards. Furthermore, both indoor and outdoor measurements were conducted to evaluate the influence of external conditions on indoor air quality. The concentration of CO2 indoors was utilized as an indicator of ventilation quality. Furthermore, the District Secretariat for the Environment has established a network of Low-Cost Sensors (LCS) to supplement its existing 19 air quality stations that meet legal standards. This network aims to promote citizen science projects. The performance of seven sensor brands was assessed by co-locating them with regulatory grade stations (MetOne BAM 1020) and evaluating them using the EPA Particulate Matter LCS test technique. The LCS were subsequently deployed in certain regions of the city that were selected based on a comprehensive review of socio-economic and environmental data, as well as the presence of vulnerable people and government initiatives aimed at mitigating pollution. Currently, Bogotá has implemented 17 Low Emission Zones (LEZ) throughout the city, with a specific focus on the southwest area. This region is known to have the highest levels of particulate matter. Finally, a system of 24 self-assembled sensors was installed in public schools located in the municipality of Soacha, which is situated to the southeast of Bogotá. This program was created to streamline the progress of environmental education projects among students and to supplement the three current air quality monitoring stations of the environmental authority. In addition, several theoretical and practical seminars were implemented to instruct instructors on the importance of monitoring the air quality in their environment and protecting the well-being of their students.

Keywords: Air Quality monitoring, Low-Cost Sensors, particulate matter, vulnerable communities