MEASUREMENT OF INDOOR MAGNETIC FIELD DUE TO MAINS CURRENT WITHIN SEET BUILDING ENGINEERING LABORATORY AND ELECTRICAL LABORATORY COMPLEXES OF FEDERAL UNIVERSITY OF TECHNOLOGY AKURE (FUTA)
ABSTRACT
The 21st Century man is exposed to a very high amount of magnetic fields in his environment. This is mainly due to the ubiquitous use of electricity and other technological devices, which are the major sources of magnetic field pollution. According to The Internal Commission on Non Ionising Radiation (ICNIRP), The World Health Organisation (WHO), The Scientific Committee on Emerging and Newly Identified Health Risks (SCENIHR) and other EMF regulating bodies, over exposure to magnetic fields causes numerous health problems. In most cases, people are not aware that they are overexposed until the health effects of overexposure such as Cancer, Leukemia, and other health implications highlighted in this project, are noticed. This project provides information on the level of exposure to magnetic fields of personnel within the School of Engineering and Engineering Technology Building, The Engineering Laboratory building and the Electrical Laboratory building. This was done using a Magnetic Field Strength Meter. Measurements were carried out within the buildings only when there is availability of power supply with electrical appliances turned on. Measurements were taken severally at all the locations and the average value computed to give the actual magnetic field strength. Values obtained were compared with the Internal Commission on Non Ionising Radiation (ICNIRP) standard for magnetic field exposure and appropriate recommendations were made.
CHAPTER ONE
INTRODUCTION
Magnetic fields are found everywhere on the Earth’s surface. They originate from natural and artificial sources. The main natural source is the Magnetic Field of the Earth itself, while human technological development has led to an increase in the presence of additional Magnetic Fields in the Earth’s environment. Power distribution systems among so many others are just a few of many examples of technologies producing Magnetic Fields. The most widespread artificial Magnetic Fields are those generated by the production, distribution and use of electric current, which are usually called Power-Line Frequency Magnetic Fields.
Electromagnetic fields are created whenever electricity passes through a conductor. Actually, two interdependent fields are created; an electric field and a magnetic field. (Ali & Hardiman, 2005) The strength of the electric field depends on the voltage being carried, while the magnetic field strength depends on the amount of current being carried (amperage). Magnetic fields due to mains current are typically represented as sinusoidal in shape, alternating at the frequencies of 50 Hz in Europe and 60 Hz in North America and fall within the very low frequency (VLF) and Extremely Low frequency (ELF) ranges (Corbacio, 2013). In fact, because of the individual’s proximity to household appliances powered by ac (mains current), magnetic fields produced by the use of mains current is often more pronounced than those produced by transmission lines strung on high towers. (Ali & Hardiman, 2005).
Due to the ubiquitous usage of electric power, human beings are highly exposed to magnetic fields by a great magnitude. For a long time, the possibility of an influence of weak magnetic fields on the well-being of human beings has simply being ignored. However, the ever increasing knowledge of the biological effects of not just Electromagnetic Radiations but also low frequency electromagnetic fields as well as numerous epidemiological studies with focus on a possible increase in the risk of cancer through Electromagnetic field exposure has also led to researches on other health issues caused by over exposure to Electromagnetic fields (Adey, 1993).