Measurements and reduction of microwave oven electromagnetic leakage

Abstract

Public believed that radiation leakage from microwave ovens was similar to atomic radiation that could lead to serious health problems, including cancer. For many years up to now, domestic microwave ovens were not considered to leak levels of microwave radiation that caused concerns; consequently, they have not been regularly monitored. According to Australian Standard 3301, the maximum allowable leakage from a microwave oven is 5 mW/ cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> at 5 cm distance from the oven surface. These safety standards were based on the belief that the only danger from exposure to high intensity microwave energy is a thermal or overheating effect. Since the leakage from microwave oven becoming a new issue, this paper is proposed to investigate the effect of oven leakage, the issue of emission levels versus exposure levels and the application of power density measurements in order to measure the leakage from microwave ovens. There are six measurements have been conducted and it is found that all of the microwave ovens are having leakage. From the measurement results, only one microwave oven gives a value of 10.19 mW/cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> which is exceeded the limit of 5mW/cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> . Due to this reason, ti is suggested to use Conductive Transparent Film to reduce the leakage from the microwave oven, since it is a relevant way in shielding to prevent unwanted leakage from the microwave oven. The result shows that the Conductive Transparent Film can reduce the microwave oven leakage by about 12.39 dB to 8.53 dB.