Performance analysis of radiation hazard meters at radio frequencies

In the last decades, public concerns in relation to possible health effects of exposure to electromagnetic radiation (EMR) at radio frequency (RF) have increased dramatically. As a result, many EMR measurements are conducted around different sources, mainly cellular base stations, in order to assess the exposure levels around them and ensure their compliance with the exposure limits. These measurements are generally conducted with commercial EMR meters, also known as radiation hazard meters. The meters differ from each other by parameters such as their type, nominal frequency range response and nominal field intensity range. Most meters measure the amplitude of the electric field (EF) using RF diodes. Few of them measure the magnetic field (MF) using loop detectors, or the power density using special thermocouple techniques. Since the angular response of a single detector probe is strongly dependent on the polarization and the direction of the impinging wave, an array of 3 orthogonal detectors is commonly used in order to achieve an isotropic response. Proper use of such meters necessitates annual calibration as described in IEEE Std.1309. It should be emphasized that the calibration process does not include any change in the meter itself. This work presents a preliminary analysis of the calibration results of approximately 150 meters that were calibrated at Soreq NRC EMR laboratory