## 3 Analysis of the Variation of the Air Quality in the Different Living Rooms of a Single Building  
This study aimed to conduct an examination of the variations in air quality across different rooms within a single building, specifically a bedroom, a kitchen, and a bathroom. Three identical systems were designed to collect sensor data continuously for 10 days. To ensure consistency and reduce the impact of time-related variability, measurements were systematically taken at 1:00 PM each day. A 30-min sensor calibration period was conducted before each data recording session to ensure the accuracy and reliability of the gathered data [33]. This methodical approach allowed for a detailed exploration of the air quality dynamics unique to each of the examined living spaces. Figure 4 presents a comparison of the discrepancies between the three identical systems. These figures illustrate that there are minimal differences between the systems. Due to the meticulous calibration process, a lower level of error was achieved than initially anticipated by the manufacturers. The investigation generated comprehensive data on four key air quality metrics: IAQ, humidity, CO\({}_{2}\) levels, and VOC. Each metric was meticulously recorded and evaluated for the three rooms under study. Figure 5 illustrates the CO\({}_{2}\) levels, Figure 6 shows the humidity data, Figure 7 depicts the findings related to IAQ, and Figure 8 displays the VOC measurements. This study aims to disclose the distinct air quality variations observed within different residential zones by analyzing the patterns depicted in these figures. It focuses on IAQ and aims to shed light on the underlying causes affecting it. The study paves the way for future research and interventions to improve living conditions. The outcomes of this analysis provide a basis for making informed decisions and adopting evidence-based strategies to promote healthier and eco-friendier indoor environments. Figure 3: Results of temperature, humidity, VOC, and CO\({}_{2}\) calibrations. Figure 5 shows the difference in CO\({}_{2}\) levels between the kitchen, bathroom, and bedroom, with the kitchen having the highest CO\({}_{2}\) concentrations. The significant disparity in CO\({}_{2}\) concentrations, with the kitchen exhibiting the highest levels, suggests the presence of underlying factors influencing indoor air quality dynamics within each space. In the kitchen, the elevated CO\({}_{2}\) levels may stem from various sources, including inadequate ventilation, the use of gas appliances, and the accumulation of airborne contaminants emitted during cooking activities [27,41]. Additionally, factors such as poor air circulation and limited airflow contribute to the buildup of CO\({}_{2}\) in this area. Conversely, the bathroom demonstrates relatively lower CO\({}_{2}\) levels compared to the kitchen, indicative of improved ventilation practices or the presence of exhaust fans that facilitate the removal of indoor air pollutants. However, despite the apparent ventilation improvements, the use of cleaning products and air fresheners in the bathroom may introduce VOC into the air, contributing to a decline in overall air quality when compared to the bedroom environment. Furthermore, it is crucial to consider the frequency and duration of  
Figure 4: Temperature (**a**), humidity (**b**), VOC (**c**), and CO\({}_{2}\) (**d**) comparisons of the three systems. Figure 5: Dataset for carbon dioxide. occupancy in each space, as human activities can significantly influence indoor air quality parameters. For instance, prolonged occupancy in the kitchen during meal preparation may lead to higher CO2 levels due to increased metabolic activity and exhalation of occupants. The observed differences in CO2 levels among the kitchen, bathroom, and bedroom underscore the complex interplay of various factors, including ventilation efficiency, human activities, and the presence of indoor pollutants.