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electric fields generated by other common household/business sources and well below the various <br />state and international organization established guidelines. <br />The maximum calculated electric field on the entire length of project, directly beneath transmission <br />centerline at 3.28 feet above ground is estimated to be 1.09 kV/m. This maximum calculated <br />electric field is approximately 14 percent of the 8 kV/m guideline historically recommended by the <br />Minnesota Environmental Quality Board (EQB) and the Commission in other route permit <br />proceedings and again, well below any of the national and international recognized electric field <br />guidelines as identified in Tables 10 and 11. <br />Magnetic Fields <br />Electric current passing through a conductor produces a magnetic field in the area surrounding the <br />wire. Similar to electric fields, magnetic fields are strongest near the conductor and diminish with <br />distance. Magnetic fields, however, are not shielded by most common materials and easily pass <br />through them. The magnetic field may also be called magnetic flux density and is measured in units <br />of milligauss (mG) or microtesla (µT). <br />We encounter magnetic fields from every -day things such as radar and microwave towers, <br />television and computer screens, motors, fluorescent lights, microwave ovens, cell phones, electric <br />blankets, house wiring and hundreds of other common electrical devices. <br />The general wiring and appliances located in a typical home can produce an average background <br />magnetic field of 0.5 mG to 4 mG (EPA, 1992). A U.S. government study conducted by the EMF <br />Research and Public Information Dissemination Program determined that most people in the <br />United States on average are exposed to magnetic fields of 2 mG or less daily, and varies by <br />individual (NIEHS, 2002). Table 13 summarizes the average level of magnetic fields of common <br />appliances. <br />Table 13: Typical Magnetic Fields (mG) of Common Appliances <br />Source <br />Distance from Source <br />0.5 foot <br />1 foot <br />2 feet <br />4 feet <br />Baby Monitor <br />6 <br />1 <br />- <br />- <br />Computer Displays <br />14 <br />5 <br />2 <br />- <br />Fluorescent Lights <br />40 <br />6 <br />2 <br />- <br />Copy Machines <br />90 <br />20 <br />7 <br />1 <br />Microwave Ovens <br />200 <br />4 <br />10 <br />2 <br />Electric Pencil Sharpeners <br />200 <br />70 <br />20 <br />2 <br />Vacuum Cleaner <br />300 <br />60 <br />10 <br />1 <br />Can Opener <br />600 <br />150 <br />20 <br />2 <br />Color Televisions <br />NA <br />7 <br />2 <br />- <br />Source: NIEHS, 2002 <br />Environmental Assessment <br />PUC Docket E002/TL-11-223 Page 34 <br />