## 4 Discussion  
This study comprehensively assessed the DC and EMF exposure levels of Wi-Fi 6 networks under various scenarios, addressing the influence of bandwidth, radio conditions, user devices, and multi-user environments. The results reveal significant findings that provide valuable insights into the realistic exposure characteristics of Wi-Fi 6 and their implications for public health and regulatory compliance. The measured DC showed a clear dependency on the application type and bandwidth. High-throughput applications like FTP file transfers exhibited stable and the highest DC (e.g., the maximum mean DC of 94.2% for FTP downloads at 20 MHz bandwidth), while pre-buffered services like YouTube video streaming demonstrated a bursty transmission pattern with positively skewed DC distributions. DC generally decreased for most applications as bandwidth increased, reflecting improved transmission efficiency. However, for certain applications such as video calls, DC either remained stable or increased due to higher traffic demands at higher data rates, emphasizing the role of QoS requirements in shaping DC behavior. The authors of [9] reported DC data for 802.11a/g networks under different internet services. Due to the significantly enhanced throughput of Wi-Fi 6, the DC values for most applications reported in this study are notably lower than those in [9], particularly for YouTube 1080p video streaming, where the maximum mean DC was 87.4% in [9], compared to 5.3% in this work. However, the reported mean DC for video calling and file transfer in [9] is lower than the corresponding values in this study. This discrepancy can be attributed to differences in application requirements and technological advancements:  
Figure 13: Exposure levels at different UDs (laptop, mobile phone, tablet, and UWiA), center, and AP measured in the multi-user scenario for different DCs (all 4 UD-scenario DCs). for video calling, the lower DC in [9] likely reflects the lower QoS requirements at the time, such as reduced resolution and frame rates, resulting in lower traffic demands; for file transfer, the higher DC in this study is explained by the improvements in OFDMA and MIMO technologies introduced in Wi-Fi 6, which significantly enhance time-domain efficiency and channel capacity, allowing for more consistent and sustained transmissions. Poor radio conditions significantly elevated DC values for most applications, e.g., AP-side 4K video streaming mean DC increased from 3.1% to 19%, FTP downloads increased from 43.1% to 88.6%, except for FTP upload, where AP-side mean DC decreased from 21.1% to 8% due to reduced uplink transmission efficiency. This highlights the impact of retransmissions and lower MCS under degraded SNR, which increases the duration of active signals and potentially elevates exposure levels. These findings underscore the need to consider radio-condition variations in real-world exposure assessments. Ref. [14] investigated the mean DC of uplink traffic for various network applications over 15 min under good, moderate, and bad radio conditions on 802.11a/g networks. They reported that DC increased with deteriorating signal quality, ranging from 0.21% to 73.7%. Although [14] focused on uplink signals, while the measurements in this study under the worst radio conditions primarily addressed downlink signals at the AP, a direct quantitative comparison is not feasible. However, the main conclusion aligns between the two works: radio channel quality significantly impacts DC. Furthermore, their observation that the average DC for FTP upload increased from 56.8% under good radio conditions to 73.7% under bad radio conditions corroborates the corresponding trends reported in this study. Since the AP in this study supports MU-MIMO and beamforming, signal power distribution may vary depending on the device location. However, to minimize bias, measurements were taken under controlled conditions with the UD positioned at a fixed LOS distance for single-user scenarios. The exposure levels varied significantly across different UDs.