Assessment of radio frequency exposures in schools, homes, and public places in Belgium

Characterization of exposure from emerging radio frequency (RF) technologies in areas where children are present is important. Exposure to RF electromagnetic fields (EMF) was assessed in three "sensitive" microenvironments; namely, schools, homes, and public places located in urban environments and compared to exposure in offices. In situ assessment was conducted by performing spatial broadband and accurate narrowband measurements, providing 6-min averaged electric-field strengths. A distinction between internal (transmitters that are located indoors) and external (outdoor sources from broadcasting and telecommunication) sources was made. Ninety-four percent of the broadband measurements were below 1 V m(-1). The average and maximal total electric-field values in schools, homes, and public places were 0.2 and 3.2 V m(-1) (WiFi), 0.1 and 1.1 V m(-1) (telecommunication), and 0.6 and 2.4 V m(-1) (telecommunication), respectively, while for offices, average and maximal exposure were 0.9 and 3.3 V m(-1) (telecommunication), satisfying the ICNIRP reference levels. In the schools considered, the highest maximal and average field values were due to internal signals (WiFi). In the homes, public places, and offices considered, the highestmaximal and average field values originated from telecommunication signals. Lowest exposures were obtained in homes. Internal sources contributed on average more indoors (31.2%) than outdoors (2.3%), while the average contributions of external sources (broadcast and telecommunication sources) were higher outdoors (97.7%) than at indoor positions (68.8%). FM, GSM, and UMTS dominate the total downlink exposure in the outdoor measurements. In indoor measurements, FM, GSM, and WiFi dominate the total exposure. The average contribution of the emerging technology LTE was only 0.6%

In-situ RF exposure in schools, houses, and public places

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Improving air filter efficiency as a strategy to reduce children’s exposure to traffic related air pollutants in energy-efficient classrooms

This study was organised to quantify the effect of upgrading the filter efficiency in balance ventilation systems on indoor exposure to traffic-related air pollution, in 4 primary school classrooms. The standard air filters (EU F7) were compared with more efficient EU F9, and with F7+active carbon filters. Particulate matter (PM), ultrafine particles (UFP), black carbon (BC), PM2.5, organic/elemental carbon in PM2.5 (EC/OC), and NO2 were quantified, air tightness and air supply rates were assessed and pupils’ indoor comfort was surveyed. Analysis of indoor air as function of outdoor air and filter type indicated a significant but small reduction of indoor levels when upgrading the filter, except for PM10, TSP and UFP. The indoor comfort survey indicated a small but significant and positive effect as well