High Noon for Mobile Networks: Short-Time EMF Measurements to Capture Daily Exposure

Exposure from radio base stations (BSs) is often only monitored over short periods, typically during the daily hours of working days. However, BS exposure can vary throughout the day and even between working days and weekends or holidays. The objective of this study is to determine to what extent short-term exposure measurements taken during daily hours are representative of daily average exposure levels. To achieve this goal, we analyzed a set of long-term measurements taken by monitoring units located in sensitive areas, which are characterized by a homogeneous distribution of users over working hours, such as hospitals, train stations, and university centers. Our results reveal that 6-min measurements taken on working days can overestimate the average exposure level over 24 h if taken over a wider time interval than that commonly considered for peak traffic and, therefore, higher exposure. Based on the common pattern of exposure over time in various locations, an extrapolation factor is proposed to predict daily exposure levels from short-time measurements.