RESUMO
Extremely low frequency electromagnetic field [ELF-EMF] is harmful to human body and causes various diseases like cancer. ELF-EMF is mainly produced by surgical or anesthetic equipment in operating room. However, it can be made by surrounding electricity without electric device. We measured it in an empty operating room of our hospital over two days and nights. The intensity of ELF-EMF was measured as two-second interval for two days in an empty operating room. One day was divided to three groups; night, morning, and afternoon. Each group continued for three hours due to capacity of ELF-EMF instrument. All of electrical devices were off including lamp, computer and air conditioner. Groups were compared using one-way ANOVA. P<0.05 was considered significant. Mean value of ELF-EMF during 1st and 2nd night was 1.9459 and 1.9486 respectively. It was lower than data of morning and afternoon [P<0.001]. All values [100%] were above 2 mG [micro-Gauss] in daytime. In night time, most of ELF-EMF [99.9%] was below 2 mG. The intensity of ELF-EMF is higher in an empty daytime operating room than at night time