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Emf Voltage

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Inspections for Electromagnetic Fields (emfs) Atlanta

Atlanta Inspection provides EMF inspection reading at affordable cost.people are routinely exposed cause health effects?We are number one in the measurement service.


Can the electric and magnetic fields (EMF) to which people are routinely exposed cause health effects? What are sources of EMFs, and when are EMFs dangerous?


EMF (or ElectroMagnetic Field) is a broad term which includes electric fields generated by charged particles in motion, and radiated fields such as TV, radio, hair dryer, and microwaves. Electric fields are measured in units of volts per meter or V/m. Magnetic fields are measured in milli-Gauss or mG. The field is always strongest near the source and diminishes as you move away from the source. These energies have the ability to influence particles at great distances. For example, the radiation from a radio tower influences the atoms within a distant radio antenna, allowing it to pick up the signal. Despite the many wonderful conveniences of electrical technology, the effects of EMF on biological tissue remains the most controversial aspect of the EMF issue, with virtually all scientists agreeing that more research is necessary to determine safe or dangerous levels.


Research since the mid-1970s has provided extensive information on biological responses to power-frequency electric and magnetic fields. The Electric and Magnetic Fields (EMF) Research and Public Information Dissemination (RAPID) Program was charged with the goal of determining if electric and magnetic fields associated with the generation, transmission, and use of electrical energy pose a risk to human health. The fact that 20 years of research have not answered that question is clear evidence that health effects of EMF are not obvious and that risk relationships, if risk is identified, are not simple. Because epidemiologic studies have raised concerns regarding the connection between certain serious human health effects and exposure to electric and magnetic fields, the program adopts the hypothesis that exposure to electric or magnetic fields under some conditions may lead to unacceptable risk to human health. The focus of the program is not only to test, as far as possible within the statutory time limits, that hypothesis for those serious health effects already identified, but to identify as far as possible the special conditions that lead to elevated risk and to recommend measures to manage risk.


Electromagnetic hypersensitivity (ES) is a physiological disorder characterized by symptoms directly brought on by exposure to electromagnetic fields. It produces neurological and allergic-type symptoms. Symptoms may include, but are not limited to, headache, eye irritation, dizziness, nausea, skin rash, facial swelling, weakness, fatigue, pain in joints and/or muscles, buzzing/ringing in ears, skin numbness, abdominal pressure and pain, breathing difficulty, and irregular heartbeat. Those affected persons may experience an abrupt onset of symptoms following exposure to a new EMF such as fields associated with a new computer or with new fluorescent lights, or a new home or work environment. Onset of ES has also reported following chemical exposure. A concerted effort to provide scientifically valid research on which to base decisions about EMF exposures is under way, and results are expected in the next several years. Meanwhile, some authorities recommend taking simple precautionary steps, such as the following:



  • Increase the distance between yourself and the EMF source sit at arms length from your computer terminal.

  • Avoid unnecessary proximity to high EMF sources dont let children play directly under power lines or on top of power transformers for underground lines.

  • Reduce time spent in the field turn off your computer monitor and other electrical appliances when you arent using them.


The Office of Technology Assessment of the Congress of the United States recommends a policy of prudent avoidance with respect to EMF. Prudent avoidance means to measure fields, determine the sources, and act to reduce exposure.



  1. Detect EMFs in your home and work environment. It is good to know where the sources of EMF are in your everyday world and how strong these sources are. Is there wiring in the wall behind your bed that you dont even know about? Is the vaporizer emitting strong fields in the babys room? How much EMF are you and your family getting from the power lines in the street? Even hair dryers emit EMFs. Home inspectors often have meters to measure EMFs, or they can be purchased and shared with friends.


  2. Diminish your exposure to the EMFs you find. Determine how far you must stay away from the EMF emitters in your home and work environment to achieve less than 2.5 mG of exposurethe microwave oven, the alarm clock, the computer, and so on. Rearrange your furniture (especially the beds, desks, and couches where you spend the most time) away from heaters, wiring, fluorescent lights, electric doorbells, and other EMF hot spots. Where practical, replace electric appliances with non-electric devices. Where practical, replace electric appliances with non-electric devices. Have an electrician correct faulty high EMF wiring and help you eliminate dangerous stray ground currents. Consult a qualified EMF engineer at 404 680-4578 if necessary. Contact Accurate Home Inspection Field Testing for a test reading in your home for 79.95 in your area.

  3. Shield yourself. Use shielding devices on your computer screen and cellular phone. Add shielding to your household wiring, circuit box, and transformers.


Electric fields in the home, on average, range from 0 to 10 volts per meter. They can be hundreds, thousands, or even millions of times weaker than those encountered outdoors near power lines. Electric fields directly beneath power lines may vary from a few volts per meter for some overhead distribution lines to several thousands of volts per meter for extra high voltage power lines. Electric fields from power lines rapidly become weaker with distance and can be greatly reduced by walls and roofs of buildings.


Magnetic fields are not blocked by most materials. Magnetic fields encountered in homes vary greatly. Magnetic fields rapidly become weaker with distance from the source.










The chart on the left summarizes data from a study by the Electric Power Research Institute (EPRI) in which spot measurements of magnetic fields were made in the center of rooms in 992 homes throughout the United States. Half of the houses studied had magnetic field measurements of 0.6 mG or less, when the average of measurements from all the rooms in the house was calculated (the all-room mean magnetic field). The all-room mean magnetic field for all houses studied was 0.9 mG. The measurements were made away from electrical appliances and reflect primarily the fields from household wiring and outside power lines.


If you are comparing the information in this chart with measurements in your own home, keep in mind that this chart shows averages of measurements taken throughout the homes, not the single highest measurement found in the home.




Magnetic fields close to electrical appliances are often much stronger than those from other sources, including magnetic fields directly under power lines. Appliance fields decrease in strength with distance more quickly than do power line fields.


The building Inspector Code Enforcement Professional Certification Program adopted by the Association provides a means of gaining recognition of the competency levels acceptable for inspection responsibilities and improved professional standing in the community.

SBCCI (Southern Building Code Congress International)
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Member Housing Institute, Inc
CPHB (certified professional home builders

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Help please.?
I know how to do the part a, but don't know how to do part b. Here is the question: thank you A 15 m long wire having a resistance of 2.0 ohms/m is moved away from you at 10 m/s. While it is moving it cuts across a magnetic field having a strength of 0.50 N/A.m. The field is directed downward into the page. a) the magnitude of the induced emf(voltage) answer: 75v b) the current in the wire.

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an equation for the ph of a solution with respect to the measured emf (voltage)?


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Physics: Induced voltage question, help?
Q: Is it possible to induce a constant emf (voltage) for an infinite amount of time? Explain. My prof said something about accumulation of charges; thus no, but I need some more explaination for this question. Thank you.

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The magnetic field perpendicular to a circular loop of wire .25m in diameter is changed from +0.72T to -0.12T.?
The magnetic field perpendicular to a circular loop of wire .25m in diameter is changed from +0.72T to -0.12T in 65 ms. Calculate the induced emf. Induced emf = voltage? Not sure how to go about this problem.

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From mechanical to energy?
A mass is winded via string aroung a flywheel and allowed to fall a specific height before detachement. The flywheel is connected to a small DC motor via gears and starts generating electricity once the mass is allowed to fall.. Now without the DC motor ( generator) the equation of energy balance is: mgh = (0.5 x m x v^2) + (0.5 x I x w^2) + ( 0.5Iw^2 x (n1/n2) where I is the moment of inertia of flywheel and w is the angular velocity ( which should be equal to the angular max velocity at point of mass detachment) n1 = number of revs of flywheel before detachement of mass n2 = number of revs of flywheel after detachement the third term in the equation is the work done to overcome friction. Now the question is : What form is the equation going to have when a DC motor is attached to the flywheel to be allowed to transform rotational energy to electrical? mgh = ? the electrical energy is in the form of UIt 2. The emf (voltage) generated by the generator is increasing linearly with time until the flywheel reaches the max angular speed (ie point of detachement) After that it falls linearly until it reaches 0 like the flywheels angular velocity.. how do u calculate the electrical energy? I know U and i know the time from the graph obtained... The graph is like a triangle...

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Kirchoff Loop Rule - Physics Help Please :)?
In this diagram: http://www.webassign.net/walker/21-35alt.gif IF R =11 Ohms and EMF ( Voltage ) = 12 V And Point A Is grounded to 0V How would you find the voltage at points B and C? I thought Point B would be 12 but apparently it is wrong.

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The current in a simple RL circuit is greatest?
after one time constant after the emf has been connected for a long time and the coil is fully energized after the emf voltage source is turned off when the emf voltage is first applied and the coil begins to store energy

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EMF and high-voltage power lines: A case study in Michigan : hearing before the Subcommittee on Investigations and Oversight of the Committee on ... Congress, first session, August 6, 1991
By: United States
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