Intensity of electromagnetic radiation in residential areas of Chongqing city

Objective To investigate the level and characteristics of electromagnetic radiation in urban residential environment.Methods According to national standard recommendations,we selected four residential districts.The electromagnetic radiations were measured at outdoor points,every floor in the selected buildings,and in living rooms.Results The average electric field intensity and power density of 100KHz-3GHz freguency electromagetic radiations did not exceed the limits of the national standard.But the electric field in tensity of probe 7(100KHz-3GHz)was close to the first class limit of the nationals tandard(<5V/m).There was no 5Hz-100KHz electrom agetic radiation.In the same standing state,the mean values of electrical field strength of 5Hz-1KHz and 1KHz-100KHz with electronic appliance operation were higher than those without electronic appliance operation(P<0.05).And with electronic appliance operathan tion,the mean value of electrical field intensity of 5Hz-1KHz in the standing state was higher that of in the sitting state(P<0.01).Conclusion In urban residential environments,the maine lectrom agnetic radiation is lowintensity radio waves with mixed frequencies.The extremely lowfrequency electrom agnetic radiations(30Hz-300Hz)at indoor environments might have some health impact.