## 4 Analysis of the Impact of Fragrance Products on Indoor Air Quality  
In modern scientific inquiry, IAQ is a crucial concern due to the release of VOC from household cleaning products and chemical interactions. These VOCs can significantly degrade IAQ, potentially resulting in adverse health outcomes and discomfort for residents. This study conducted an analysis of the effect of household products that emit VOC on IAQ. The study included commonly used items such as aromatic diffusers, perfumes, and aerosol sprays, which are often used for air freshening, personal care, and cleaning. To measure the impact of these products on IAQ, advanced analytical methods were used to measure key IAQ parameters, including concentrations of CO\({}_{2}\) and VOC. Accurate CO\({}_{2}\) measurements are essential in evaluating indoor air ventilation efficiency and the breathing activity of occupants. VOC levels, on the other hand, indicate the release of potentially hazardous compounds into the environment. Figure 15 shows the impact of aromatic diffuser and perfume on CO\({}_{2}\) (a), IAQ (b), and VOC (c). Figure 15a presents the complete results on CO\({}_{2}\) concentrations, providing insight into the effect of household items on indoor air ventilation. Analyzing CO\({}_{2}\) levels is crucial for evaluating air exchange and identifying high CO\({}_{2}\) levels, which may indicate poor ventilation. Figure 14: Correlation between VOC and CO\({}_{2}\). Figure 15: Impact of aromatic diffuser and perfume on CO\({}_{2}\) (**a**), IAQ (**b**), and VOC (**c**) with predicted values and marked air quality indexes marked in Table 1.  
The figure reflects the cumulative effect of the household products under study on the ambient air conditions. Figure 15b illustrates the findings related to IAQ, which encompasses a variety of elements such as VOCs, particulate matter, and other airborne contaminants that affect the healthfulness of indoor environments. By examining Figure 15b, we can gain a better understanding of the impact that common household products have on IAQ. Figure 15c presents a detailed analysis of VOC data, identifying the specific VOC and their corresponding concentrations detected throughout the experiment. This thorough examination enables the precise identification of the predominant and potentially hazardous VOC emitted by each household product, enhancing the overall understanding of sources of indoor air pollution and associated health risks [28; 45]. The data were subjected to analysis using a predictive model [46]. The predictive model demonstrates robust performance, as evidenced by the close alignment between the actual data points and the predicted values. In the majority of instances, the predicted values are closely aligned with the actual data, thereby demonstrating the efficacy of the model for prediction across diverse environmental contexts. It is important to note the behavior of the predictive model when encountering spikes in the actual data. The observed data points tend to exhibit higher values during these spikes, whereas the predicted values are somewhat lower. This discrepancy arises from the fact that the predictive model is based on a substantial volume of training data, which enables it to accurately predict general trends but may result in the smoothing out of sudden, short-term fluctuations such as spikes. These spikes in the actual data represent specific conditions or anomalies that deviate from the typical environmental patterns captured by the model. Nevertheless, the predictive model provides a reliable basis for air quality analysis and can be optimized to improve its performance in scenarios where air quality is moderately or very sensitive. The experiment began with the introduction of an aromatic diffuser located approximately five meters from the sensing equipment. The diffuser contained 50 mL of essential oil, and diffusion commenced at 15:01, with the concentration peaking at 15:03, followed by a gradual dispersion of VOC into the surroundings.