Monday, 28 March 2011
Electromagnetic Fields (EMF) Basics
In recent years, many paranormal investigators have adopted Electromagnetic Field (EMF) detection devices as a plausible tool for detecting the presence of ghosts and calculating the approximate location of spirit energies. In fact, it is probably the paranormal community which accounts for a very large percentage of the sales of EMF detection and monitoring equipment gear. However, only a handful of ghost hunters can fully explain the principles behind EMF and demonstrate proper use of the detection equipment.
Hopefully, this article will help to explain the basics of EMF detection. This article is not intended to be a technical treatise on electromagnetic fields, waves and radiation, but rather is aimed towards informing our ghost hunting brethren of some little known facts and information that might prove to be useful to them.
Electromagnetic Field Detectors
During the cellular telephone boom of the early 1990's, many theories abounded concerning the ill effects generated to the human body from exposure to ELF (extremely low frequency) magnetic fields in numerous scientific and medical journals. Theories ranged from those explaining that EMF exposure could possibly effect the body's immune system to theories which proposed that EMF exposure could be directly correlated to certain types of cancer.
Although evidence proving a direct "cause and effect" link between EMF and health problems has never been established, prestigious and recognized authorities (including the United States Environmental Protection Agency) have recommended "prudent avoidance" of ELF magnetic fields on a prolonged basis until further research leads to more conclusive results.
So, to serve the public's interest, many companies began developing simple equipment to both detect the presence of ELF magnetic fields and to measure their relative strength. Almost anyone who has purchased an EMF detector and read through the directions included with the unit has an understanding of how to operate the unit and a strong idea of where to find magnetic fields within the home. Common sources for household EM readings include such mundane objects as computer monitors, cellular telephones, bedside clock radios, and microwave ovens.
There are many different models of EMF detector currently available on the market, ranging from basic EM detection circuit boards (retailing around $5 each), to limited range user friendly models (the NL-PSI members all own ELF-Zone EMF detectors purchased in an e-Bay auction for $10 each), to incredibly sensitive units such as the Natural Trifield Meter (expect to pay a minimum of $150 for the basic model up to $300 for the more advanced models). EMF detection equipment is widely available from numerous sources on the world wide web and mail order scientific supply houses such as Edmund Scientific.
General Information concerning EMF
The electromagnetic spectrum covers an enormous range of frequencies ranging from invisible fields to visible light and beyond. These frequencies are expressed in cycles per second (i.e., Hz). Electric power (60 Hz in North America, 50 Hz in most other places) is in the extremely-low-frequency range, which includes frequencies below 3000 Hz.
The higher the frequency, the shorter the distance between one wave and the next, and the greater the
amount of energy in the field. Microwave frequency fields, with wavelengths of several inches, have enough energy to cause heating in conducting material. Still higher frequencies like X-rays cause ionization—the breaking of molecular bonds, which damages genetic material. In comparison, power frequency fields have wavelengths of more than 3100 miles (5000 km) and consequently have very low energy levels that do not cause heating or ionization. However, AC fields do produce weak electric currents in conducting objects, including people and animals.
In order to understand how electromagnetic fields operate within a home, we must first understand some of the basic principles of electricity. Without going into great detail, it is safe to assume that most people are aware that the electricity which powers their homes is brought to them by an enormous power system which covers most of the country.
From giant generators in plants fueled in a variety of ways (nuclear power plants, hydroelectric power plants, etc.), the voltage is increased by setup transformers in order to send the electricity over transmission lines to smaller substations. It is here that the voltage is decreased by the use of a step-down transformer and the power is carried along the distribution lines to a home, where a final step-down transformer decreases the voltage for energy consumption within the average home.
North America uses a 60 hertz (Hz) AC (alternating current) power system. Though a typical household is filled with electrical wiring, the typical wire contains three individual strands of wire which carry the electricity. Most household appliances utilize only one wire at a time, but the three wires are bundled together in order to keep the current cycling at different points in time. This, in turn, allows the charges to cancel one another out, resulting in an overall neutral charge (hence, alternating current). If these three wires are not run closely enough together or are improperly insulated, a "hot spot" is created and very high magnetic fields are the result.
When an electrical current travels through the wiring or into an appliance, it produces an electromagnetic field, which consists of the electric field which is always present (even when the appliance is switched off) and the magnetic field which occurs when the power is switch on to the appliance. While it is generally accepted that the electric field is harmless, it is suspected that the magnetic fields can be related to cancer or other health problems. Thus, companies have been quick to offer EMF detection devices to help the average homeowner locate and isolate areas of strong electromagnetic fields.
However, in addition to the EM present because of electrical wiring and appliance, EMF is found in nature as well. The earth itself has a unique magnetic field (referred to as a geomagnetic field) and anyone who has handled a compass is probably well aware of that fact. The earth produces EMFs, mainly in the form of DC (direct current, also called static fields). Electric fields are produced by thunderstorm activity in the atmosphere. Near the ground, the DC electric field averages less than 200 volts per meter (V/m). Much stronger fields, typically about 50,000 V/m, occur directly beneath electrical storms.
Magnetic fields are thought to be produced by electric currents flowing deep within the earth's molten core. The DC magnetic field averages around 500 milligauss (mG). This number is larger than typical AC electric power magnetic fields, but DC fields do not create currents within humans and animals like AC currents can do.
Factors as subtle as water running against certain geological stratas of rock can also produce electromagnetic fields. The sun's solar flare activity can also greatly effect the magnetic fields of the earth, as well as cosmic radiation that is able to penetrate the earth's atmosphere.
No matter the source of the EM field, all magnetic fields are measured in units called Gauss (named for Charles Friedrich Gauss, 1777-1855) or Tesla (named for Nikola Tesla, 1856-1943). While these units of measurement actually record the magnetic flux rather than the density of a field, it is unimportant for our means. Here in the United States, EM fields are measured in milliGauss (mG) while the Tesla measurements are most commonly expressed in Europe. In essence, 1mG=.01 microTesla.
For the purpose of ghost hunting, most of the EM equipment used focuses specifically on the ELF (Extremely Low Frequency) range of less than 60 Hertz and is expressed almost exclusively in terms of milliGauss (mG).
Using EMF Detectors
Before attempting to use any EM detection device as part of a ghost hunt or an investigation, it is absolutely essential that the operator has read through the instruction manual thoroughly and is familiar with operating the device. To attempt using an EMF detector as part of any serious inquiry into the paranormal without fully comprehending how to properly operate the unit is an open invitation to false-readings and misleading EMF alerts.
Most of the time, operation of an EMF detector is usually considered as simple as switching on the power and moving the unit around until it registers a source of EM radiation. However, we here at the NL-PSI strongly recommend that you first use your EMF detector in your home as a training exercise to allow you to become familiar with the various sources of EM radiation in an average household. You will often find that ELF radiation is strongest in one particular area. For example, your computer monitor at work may have its greatest EM radiation level directly in back of it, a bedside clock radio may emit EM radiation to one particular side, etc.
Most of the commercially available EMF detectors are "single-axis" meters. Although even a simple explanation of what this means can confuse most non-technical users, it is very important to understand how this property affects the measurements you take.
A magnetic field has two basic properties: Its strength (or level) which is measured in mG, and its direction. Most people have no problem understanding that magnetic field levels are measured in units of mG, but the majority of measurements taken by an inexperienced operator with a single-axis meter are flawed. The problem arises from the fact that magnetic fields are directional (remember that it is the earth's magnetic field which causes a compass needle to point to magnetic north).
Most of the time, operators simply point the meter "at" the area they are trying to measure. Although it is possible that this may lead to "correct" measurements, it is much more likely that the level indicated by the meter will be lower than the actual level present. Also, try to keep in mind that all meters have different ranges of accuracy, normally ranging from +/- 1% to +/-4%. Your instruction manual will include this information and it is important to note this factor when recording your readings.
Instead of pointing the meter "at" what is being measured, the user should try slowly and gently orienting the meter in different directions until a maximum level is indicated on the display. Turn the meter clockwise, counterclockwise, sideways, leaning forward, leaning backward, and all combination of angles and distances in between. This may seem a little awkward, but it is absolutely necessary to insure accurate readings.
Hold the meter in front of and around the source of radiation and continue to orient the meter at various angles until a maximum reading is found. If you take the time to become familiar with this process, you will find that the reading displayed is greatly affected by the orientation of the meter. This is because the magnetic field not only has a strength or level associated with it, but a direction as well. Most meters respond very well to EM fields that run across the meter from left to right (or right to left), but a very strong magnetic field running in a direction from top to bottom or front to back will show little or sometimes no reading on the display of many meters.
If it is not possible to insure that you are using your single-axis meter correctly, consider upgrading your EMF detector to a 3-axis instrument such as the Trifield Natural EM Meter or the Teslatronics Model 70. These are far more sensitive units (The TriField meter can actually pick up the EM signatures produced by the human body at a distance of ten feet, through a wall!) and are able to monitor a wide range of energy patterns, such as microwave and radio wave radiation as well as EMF.
The 3-axis meters, because of their inherent sensitivity, will get accurate readings very quickly, but have many quirks unique to their very nature. For instance, trying to measure radio frequency (RF) radiation in a room with a TriField meter may prove difficult because the meter will pick up energies being reflected from the four walls, the ceiling and floor, and even the user's body. Some paranormal investigators report that they find using the TriField meter as an active "scanning" device by moving the unit from side to side a very difficult task because of the fluctuations of the readings.
They recommend using the TriField as a stationary device. Rather than "scanning" for EM activity that might indicate a paranormal anomaly, simply let the device sit in one area and its audible alarm will alert you when it senses an unusual EM source.
Once you have spent enough time to become intimately familiar with the subtitles of operating your EMF meter and are confident in your abilities to obtain accurate readings with it, it is time to switch over to a fresh battery and try it again in the dark. Think of it as a training exercise.
With the lights off, go through your home again with the meter, focusing only on your readings. Try to keep in mind that magnetic fields can travel through walls while trying to locate the source of your readings. Once you are fully confident that you have mastered operating your meter in dark conditions, it may be time to actually try it "in the field."
EMF Detectors and Ghost Hunting
The sole reason many investigators and ghost hunters purchase an Electromagnetic Field Detector is to help them locate ghosts. This is not what an EMF detector does and it was never designed for this purpose. Its purpose is to locate sources of electromagnetic radiation and to offer a reading of the relative strength (and direction if you are a skilled and competent operator) of the EM field.
However, EMF can be a great tool to help locate possible areas of ghostly or spiritual energy if you approach the matter appropriately, because it the generally accepted theory that spirits do emit an extremely low frequency EM field (i.e. less than 60 Hz) which commonly registers between 2.0 and 7.0 mG in strength. However, these are only general guidelines, as there have been marked exceptions in field research. Some reports put the spirit energies in excess of 10.0 mG and some incidents have registered readings over 100 mG when spirits have made their presence known. Use your best judgment when recording readings!
When you begin a ghost hunt or an investigation, its is of paramount importance that you obtain accurate "background" readings of the location you are in and to make accurate notes of any source of EM radiation. If at all possible, creating a scaled map of your site and clearly marking every EMF reading you obtain and its precise location. A map like this will prove invaluable to you in helping to locate anomalies that may indicate the presence of a ghost or spirit energies.
For instance, a cemetery location is a very common site for ghost hunts. Begin in one corner of the cemetery and start taking readings approximately three feet off the ground (waist height) and begin following the first row of grave markers, taking readings as you move along. Then, follow the second row with your readings, then to the third and so forth. By the time you are done, you will have a very good idea of the EM "environment" you will be conducting your hunt in. Be sure to carefully review your map. A series of readings in a straight line may have a very earthly explanation, such as an underground power line.
The same principles may be applied to an investigation conducted indoors. While the most accurate indications of EMF which can be attributed to "paranormal" sources are obtained when the master power switch to the location is switched off and absolutely no electricity is flowing through the location, this is grossly impractical in a lot of situations. The mapping technique is highly advisable in this instance, but more care must be taken to find every single source of EM radiation in the location.
Once the background readings have been taken and the hunt/investigation is commenced in earnest, the EMF operator will continue to "scan" the area for EM readings that are anomalous. That is, you are specifically looking for any EM reading that does not have a plausible explanation or is not indicated on the map of the "EM Environment" that you have created.
Now, you must be aware that rarely does a ghost's (or spiritual energy's) EM pattern stay in one location for long. If your reading stays steady and does not fluctuate, odds are that you are reading something with a plausible explanation, such as an electrical device on the other side of a wall. The basic rule of thumb here is if the field remains constant, it's artificially generated; if it fluctuates erratically or demonstrates movement, it's "paranormal."
In any event, it is very much the responsibility of a good investigator to insure that any logical or plausible explanation is explored before declaring the readings to be attributable to a ghost or spirit energies. But, remember that you are looking for erratic fields of energy with no physical source.
The epitome of this type of phenomena are self-contained fields of EM energy that either hover in midair or demonstrate marked patterns of movement. Upon detecting such a field, it is wise to start taking photographs immediately, because these types of anomalies have a quirky habit of disappearing quickly.
The final thoughts concerning the EMF detector and the ghost hunter is it is very important to insure that the meter is maintained correctly. These are very sensitive, and often expensive, pieces of equipment that are damaged easily. Treat them delicately and take precautions to insure that your meter is not subjected to extreme shocks, like being dropped or shaken violently. Be certain to always use a fresh battery in your meter, being careful to use the recommended size and type as indicated in your instruction pamphlet. Always be sure to remove the battery if you plan to store the meter for any length of time. Also, be sure to store the unit is a cool, dry place and never, never drop your meter or allow it to be subjected to abuse. Taking the time to follow these guidelines will help to insure that your investment will continue to serve you in the field of the paranormal for years to come.