Electrical Characterization of Indoor Air Quality in the Presence of Various Natural Air Purifiers

Air pollution is a critical threat to human health and the quality of life in large cities. In this work, we electrically characterized indoor air quality in Dhaka City with a microcontroller-based advanced sensing system in the presence of 60 air purifiers. We conducted LabVIEW-controlled, fully automated, and remotely operated experiments to precisely monitor, store, and analyze the air-purifying effects in the concentrations of air quality index (AQI) parametersPM2.5, CO₂, CO, HCHO, and TVOC. These stimulants were released into the air as vapor diffused from 32 essential oils from an aroma diffuser and 27 boiled herbs/spices from a water heater. From these 59 natural substances, the stimulant concentrations were obtained using calibrated sensors and a commercial meter, and the results are referenced with those from a commercial air purifier. The best PM2.5, CO₂, and CO suppression was observed with the boiled black tea, fennel seed, and citrus peel vapor, while effective HCHO and TVOC reduction was obtained with the vapor from boiled thyme and essential oil of ginger. Decent reductions of CO₂ and CO resulted from the essential oils of lemongrass, jasmine, saffron, and strawberry. The research outcomes of this work can add great medicinal benefits and healthy alternatives to treat patients with respiratory ailments and improve the overall well-being of city dwellers.