Measurement of non-ionizing radiation (NIR) from Wi-Fi access points and microwave ovens in residential environments

Overview

Monitoring the levels of non-ionizing radiation (NIR) to which the general population is exposed is crucial, especially in residential settings. Devices such as Wi-Fi access points and microwave ovens are widespread in homes, and users are frequently in close proximity to these devices for extended periods. This study aims to measure exposure levels to NIR from typical daily scenarios, compare these values with established safety standards, and examine how equipment characteristics may affect these levels.

• Measurements conducted using the Narda NBM-520, consistent with Brazil's ANATEL inspection standard
• Tested 40 Wi-Fi access points and 50 microwave ovens
• Wi-Fi exposure—highest measured was 4.66 V/m (7.64% of safety limit) in the 2.4 GHz band
• Microwave oven exposure—72% of units had highest emissions at the door

Findings

• Wi-Fi Exposure: The highest levels were detected in 2.4 GHz loaded network scenarios. Brand/model variety impacts data dispersion, but there was no link between device age and NIR leakage.
• Microwave Ovens: Exposure hot spots typically occur in front of the door or on the left side near ventilation outlets. Older and more used ovens exhibited the highest power density levels, with all units above 0.6 W/m² showing signs of wear. Peak levels above 1 W/m² were mostly found in visibly used appliances.
• Brand did not significantly influence power density levels for microwave ovens. However, prolonged use and poor conservation state result in increased NIR emissions.

Conclusion

This study underscores the importance of monitoring NIR emitted from everyday household devices, especially Wi-Fi and microwave ovens, as these sources can expose users to measurable levels of electromagnetic fields. The findings support a clear connection between EMF exposure and factors such as device usage, age, and conservation state. While measured levels did not exceed recommended safety limits, the evidence highlights that device condition and proximity can influence exposure levels, warranting continued vigilance regarding EMF health risks in residential environments.