Assessing multi-domain impact of IAQ and noise on productivity with portable air cleaners through physiological signals

The office environment's indoor air quality (IAQ) and noise levels are critical factors that affect productivity and overall health. However, a research gap still exists on multi-domain impact of IAQ and noise on human physiological signals. The research aims to establish a comprehensive understanding of the multi-domain impact by analyzing physiological signals such as Electroencephalogram (EEG), Electrodermal Activity (EDA), eye blinks, jaw clenching, and heart rate. 30 human subjects participated in a series of tests in various indoor environments with portable air cleaner configurations. The study incorporated four scenarios with baseline condition and two noise levels. By comparing the different scenarios, the separate and combined impacts of IAQ and noise on office productivity were assessed. Meanwhile, physiological signals were collected and analyzed alongside productivity tests, which included typing and addition tasks, to determine the relationship between IAQ, noise, and office productivity. We discovered a strong relationship between EEG power and productivity, indicating that EEG power was a valuable indicator for evaluating indoor environmental quality, especially the multi-domain effects of IAQ and noise. When using the air cleaner, the relative power in the Theta, Alpha, and Beta bands indicated increased concentration and activity levels in the brain. Additionally, the increasing number of jaw clenching suggested that participants became more anxious and nervous in noisy environments. We also found that there were no gender differences for the analysis of EEG power, providing insights for future research. These findings have implications for smart control and built environment aimed at enhancing office workers' well-being and productivity.