| Objective: Along with extensive application of various kinds of communication facilities, electrical products such as computers, microwave ovens, mobile phones and high-voltage transmission lines (HVTL), environmental electromagnetic radiation pollution has become a new public health problem. In order to know the degrees of electromagnetic radiation pollution in Suzhou city and to provide a reference for the relevant agency making scientific and effective measures and hygienic standards, we carried out this study. We systematically investigated the levels of environmental electromagnetic radiation in some administrative regions of Suzhou city, electromagnetic radiation of domestic appliances, electromagnetic radiation under high-voltage transmission lines and that in enterprises.Methods: According to the requirements and methods of national hygienic standards, we divided Suzhou urban field into grid by 1km×1km, and measured the levels of environmental electromagnetic radiation on the spots of the gridding cross. We selected some domestic appliances from families in Suzhou city, and measured its electric-field intensity and the magnetic field strength within a certain distance from domestic appliances. The distributions of electric and magnetic fields generated by high-voltage transmission lines with 10KV, 35KV and 110KV were measured in different distance. In addition, we also measured the power frequency electric field of electromagnetic equipments in ten enterprises which we had selected by randomization.Results: The environmental electromagnetic radiation degree from the areas investigated in Suzhou is under the national standard as a whole, except for some points. The comprehensive electric field strength, power density in the new district of the city significantly stronger than in the old district, but in the residential quarter notably weaker than in any other places. The scope of electric-field intensity of household electric appliances which were measured is from 0.32 to 88.76V/m, and the magnetic field strength is from 0.019 to 0.109μT. Measured in 30 cm away from household electric appliances, the scope of electric-field intensity is form 1.74 to 88.76 V/m, the magnetic field strength is from 0.019 to 0.109μT, while measured in 200 cm the former is from 0.16 to 15.37 V/m, the latter is from 0.015 to 0.068μT. The electromagnetic radiation degrees of high-voltage transmission lines with 10KV, 35KV and 110KV are under the national standards. The intensity of electric field of high-voltage transmission lines ranged from 1.482KV/m to 0.0008KV/m while magnetic field from 1.324μT to 0.016μT. The intensity of power frequency electric field of the ten enterprises ranged from 7.46V/m to 3.76V/m.Conclusion: The distribution of environmental electromagnetic radiation in Suzhou urban city is uniform, the level in the new urban district is higher than the old one, but the dwelling district is lower than the other districts. The electromagnetic radiation levels of household electric appliance are different, it depends on the household electric appliances' rated power, internal structures, the outlook designs and the materials used. The electric field intensity is strong when electric drier, lamps, radios, electromagnetic oven and mobile phone are working, but weak when TV, alarm clock, cell phones are in their standby time. The highest level of electric field intensity is 20-50 meters away from the high-voltage transmission lines. The intensity of magnetic field decrease with increasing of distance, but the intensity of electromagnetic radiation increase with increasing of voltage level. The intensity of power frequency electric field of the ten enterprises did not exceed the limits. Relatively speaking, it's stronger in electronic enterprises.
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