Investigation of extremely low frequency (ELF) hot spots in the College of Science and Technology, Covenant University, Ota

The presence of Extremely Low Frequency (ELF) from electronic devices such as personal computers, laboratory equipment and television sets in selected laboratories and offices at the College of Science and Technology Building, Covenant University, Ota, Nigeria was characterized using an ELF Detection Meter. The study revealed that exposure to ELF fields could be controlled to the minimum depending on the awareness of the occupant. As with all electromagnetic fields, the ELF field decays rapidly with distance from source or hot spots. The average observed value of ELF in the offices ranged from 3.5 to 5.0 mG. A significant hot spot with ELF of approximately 10 mG in an office was detected close to the magnetic board fixed on the wall. From the results, the maximum ELF fields of between 30–50 mG were observed close to some electronic devices, while other areas recorded significant ELF fields of between 4 mG and 25 mG due to the presence of electrical internal conduit wiring with no electrical gadgets in their vicinities. Minimum ELF fields of between 0.1 mG and 0.5 mG were observed in one of the locations surveyed.