EMF Meters – A Practical Guide to using an EMF Meter
November 29th, 2011 by Eric Haney (Revised Edition)
As the field of Ghost Hunting explodes there are many amateur investigators picking up EMF (Electromagnetic Field) meters and trying to find ghosts. I see not only in TV reality shows the incorrect use of an EMF meter but in real life too. You may ask, “What makes you qualified to write a tutorial on the proper use of an EMF meter?” I am 49 years old and graduated in 1986 with an Electronics Engineering Degree. I have been in the field of electronics and technology ever since my graduation and have obtained several certificates in various aspects of electronics theory and design. I am a certified RF/EMF specialist with a broad spectrum understanding of RF and EM field science.
I first became interested in the paranormal around 1982 and after my education began applying the RF/EM Field science and theory to the paranormal. I have learned quite a bit over the years and here in this tutorial I will share some of that knowledge.
What is EMF?
EMF – [Electromagnetic Field] also known as [Electromagnetic Frequencies]
The electromagnetic field is a physical field produced by electrically charged objects. It affects the behavior of charged objects in the vicinity of the field. The electromagnetic field extends indefinitely throughout space and describes the electromagnetic interaction. It is one of the four fundamental forces of nature (the others are gravitation, the weak interaction, and the strong interaction). The field propagates by electromagnetic radiation; in order of increasing energy (decreasing wavelength) electromagnetic radiation comprises: radio waves, microwaves, infrared, visible light, ultraviolet, X-rays, and gamma rays. The field can be viewed as the combination of an electric field and a magnetic field. The electric field is produced by stationary charges, and the magnetic field by moving charges (currents); these two are often described as the sources of the field. The way in which charges and currents interact with the electromagnetic field is described by Maxwell’s equations and the Lorentz force law. From a classical perspective, the electromagnetic field can be regarded as a smooth, continuous field, propagated in a wavelike manner; whereas, from a quantum mechanical perspective, the field is seen as quantized, being composed of individual photons. (Wikipedia, 2011)
Man-made EM fields are everywhere, they are created by a plethora of electronic devices available on the market such as but not limited to automobiles, appliances, general electronics, manufacturing, electrical distribution and more. There are also natural sources of EMF that exist such as the earth’s magnetic field, rock formations, deep space radiation, and bio-electric fields from human and animal species and yes, the possibility of ghosts and other paranormal activity.
Side Note: if you are interested in learning more about EMF and its related effects on the human body please click on this “EMF Services” link.
The EMF Meter
Most all EMF meters are calibrated for use in the 50Hz or 60Hz bands. Please note that most of these EMF meters in the electric and magnetic field settings are frequency weighted from 30Hz to about 500Hz. This means that a 2mG (milligauss) magnetic field at 60Hz will display a value of about “2” on the meter, while a 2mG (milligauss) at 120 Hz will read a “4”. These EMF meters typically give a flat response of +/- 20% over 1000Hz and as the EM Field frequency increases the sensitivity decreases. Also keep in mind that most EMF meters on the market are AC type EM detectors. AC stands for Alternating Current and means that the EMF meter is sensitive to changing magnetic fields above 0 Hertz. Static EM fields require a special type of EMF meter which we will discuss later in this article.
Inside an EMF meter are some basic components such as an inductance coil, amplifier and meter or display circuits for reading values measured. The inductor coil when passed through a small changing electromagnetic field of a couple of millivolts will create a small current in the inductor core windings that is then amplified several hundred or thousand times to a few volts. This voltage is then processed sent to the display of the unit for reading. The measurement is read in Gauss or Tesla units and the scale can be adjusted according to the amount of EMF present.
How to use the proper units during measurement
It is important to understand the values and types of measurements you are taking. I see many individuals working with EMF meters calling out numbers such as ‘2’, or “I have a 4”. These numbers mean nothing without understanding what scale and unit of measure you are reading at the time. For example, a ‘2’ could be 2 milligauss, or 2 micro gauss. You could be measuring in Tesla units and these values could be micro Tesla’s. Most field measurements will be done with the milligauss units. During scientific studies, the micro Tesla unit of measurement will be used. You can convert from micro Tesla to milligauss easily with 1 micro Tesla = 10 milliGauss.
When you are documenting your findings, using the proper unit of measure will allow your data to be much more accurate and will be of better assistance to the scientific community.
Types of EMF Meters
There are several types of EMF meters in this class and they are as follows:
- Single & 3-Axis EMF Meter (Frequency Weighted)
- Single & 3-Axis EMF Meter (Flat Frequency, Non Weighted)
- Single & 3-Axis EMF Meter (Extended Range Broadband)
Frequency weighted EMF meters which are like the majority of the EMF meters sold on the market are designed to measure levels of EMF that are absorbed by the human body. This type of EMF meter will not give a true field reading at most frequencies. Even though these EMF meters can measure a large range of EM frequencies such as 30Hz to around 100 KHz accuracy falls off at the higher frequencies.
The human body will absorb these EM fields and depending on the exposure level and frequency will absorb more or less EM field radiation. The body converts these into tiny electrical currents and impulses that can cause strange phenomena to occur. Some of the symptoms of high EM exposure can be headaches, ringing in the ears, buzzing in the head, muscle aches, hallucinations, visual anomalies and more.
Starting with a 60Hz field, effects may be subtle but as the frequency doubles and triples the effects can be increased exponential. Non-Weighted frequency EMF meters are better suited for actual true EM field measurements across the rated frequency range. These type of meters are better used in the laboratory but can be used in tandem with the frequency weighted EMF meter for validation purposes. So, all this talk about frequency weighted & non-frequency weighted. Which are better? They both have their benefits in the measurement of EM fields. FW meters can give you readings which are proportionate to the human exposure level from EM fields while the NFW can give you more linear accuracy over the entire frequency range allowing you to obtain actual EM field levels. The FW meters may be better used in paranormal investigations because they represent the exposure level relative to the human body.
The Extended Range Broadband EMF Meter has an RF sensor that is frequency flat over an extended range from about 100 KHz to about 2.5GHz. Higher priced models will extend this range even further. These meters are basically the same as their counterparts but have an increased range of operation and accuracy. They are generally more expensive and the cost may not be justified in many cases.
The Natural EMF meter differs from the AC EMF meter which has been discussed up to this point. The Natural EMF meter measures static DC or natural EM fields. These fields have no alternating current (fields) and are considered to be 0Hz or static. These types of meters are usually designed to ignore AC fields and can be very useful in paranormal investigations. The natural EMF meter will be sensitive to the fields emitted from space, earth, humans, animals and etc. These very weak DC fields can be measured and recorded during an investigation to help understand the phenomena behind what may be occurring.
Interesting note; I have personally seen significant measurement values occur when a person has walked by or near the natural EM meter. In fact, I have measured occurrences of individuals walking past a room I was in and they were not even present in this room! These measurements were recorded through the wall separating that person from the meter. This can give you an idea of how sensitive these natural EM meters can be.
The average natural EM meter can measure DC or static magnetic fields from 0 to about 100 micro Tesla.
Before we go any further I feel the need to clarify one important fact. EMF meters are not ghost detectors! I have frequently seen people marketing these meters as ghost detectors which they are not. EMF meters were designed for use by electricians, power companies, the electronics industry and personal exposure studies. Both AC and DC EMF meters will detect a variety of EM fields and validation on this alone is not good practice. All data collected from a paranormal investigation or exposure study should be used in the consideration when placing a label such as “Haunted” on a location or establishment.
Most EMF meters will cover a decent range of frequencies in the EM band especially the lower frequencies in the ELF to LF bands. It is only theory that an entity or spirit can emit an EM field when it is present or trying to communicate or manifest itself. There are very few studies that can produce solid evidence on this subject as to what frequencies or EM field’s levels may be active during a manifestation of an entity. It is at this point a possible link to EMF meters and the spirit world come into play. It is possible that when a spirit or entity tries to manifest or communicate it collects energy from the surrounding area producing an EM field in the process. These EM fields are relatively low compared to other manmade sources, probably in the 10mG to maybe 100mG range. This energy fluctuation creates an electromagnetic field.
In theory, this EM field can be measured using devices such as an EMF meter. But we must be careful to not jump to conclusions and label every reading on the EMF meter from a ghost or spirit. We are surrounded by EM fields everyday and many times the readings we get from an EMF meter are most likely man made. During an investigation your EMF meter should be used to determine any and all manmade causes of EM fields. You should also try and rule out any natural EM fields as well, except maybe your ghost! 🙂
EM fields and their effect on the human body
It is a known fact that EMF levels of 30mG or higher can cause biological and hallucinogenic effects on a human subject that is hypersensitive to EM fields. These people can experience headaches, nausea, skin irritations, ringing in the ears, hallucinations, paranoia and more.
Use your EMF meter to help detect hot spots in the house or building where people may spend a considerable amount of time. A better-known term is called a “Fear Cage”, this is usually a small confined area in a basement, crawl space or room corner where the exposure to high levels of EMF may exist. You should look for faulty wires, fuse or breaker boxes, electrical outlets, appliances and so on to help understand what your client may be experiencing. Any of these and more can cause high levels of EMF and create potential problems with human exposure.
We had an investigation where a middle aged woman was experiencing night time apparitions and shadows near her bed. She claimed they only appeared at night and were of different shapes and sizes. They were described as dark or black masses and shadows. During an initial sweep of her bedroom we found a startling high level of EMF around the alarm clock on the night stand near the bed where she slept. The levels were around 300mG, which is ten times what the human exposure limit should be. The measurement extended out for about a 2-3 foot radius and then dropped off dramatically after that. No other potential sources for the shadows were found and upon replacement of the alarm clock by the client, the EMF levels were decreased and the shadows were not seen again. The client also claimed that wild dreams would occur during this period of time also. The dreams were reduced at this time also.
For more detailed information on EM fields and their biological effects please see our “EMF Services” section.
When using an EMF meter such as a Single Axis, Trifield or K-II for assisting in validation of a spiritual haunting you must remember not to rely solely on the device for evidence of a haunting. The EMF meter can be a great tool to assist the investigator once all other manmade and natural causes are ruled out. During an investigation where an EMF meter is being used for gathering evidence of a haunting, the following tips may be helpful:
- Use more than 1 EMF meter when possible. Make sure each of the meters is the same model. Place them in a row or a circle while monitoring their exposure to the EM fields. Many times a spirit or entity that may interact with the device will light up only 1 at a time. This can help confirm that is was not a contamination from a larger external EM field burst.
- If using a single axis EMF meter, remember to angle the meter towards the source you suspect may be emitting an EM field. Usually the meter will have printed on it, the sensor position or location.
- Check your settings before you take measurements, usually milliGauss is a good starting point and move the scale up or down according to your EM field.
- Make note of your scale, you could be measuring milliGauss but if your scale is .001, .01, .1, 1, 10 or 100 this can make a difference in your values recorded if misinterpreted. These values are factors of ten and a good starting point would be .01 or .1 scale. Raise the scale from there if needed.
- When using a Trifield EMF meter, there is no need to angle the meter towards the source but using a single axis meter along with a 3-axis meter can help increase the quality of data collected.
- Check your battery often; a low battery can skew your results.
- Some meters have Magnetic, Electric and RF settings. These should be self explanatory but use your Magnetic setting for most applications in paranormal investigation. The Electric settings can be used to help determine standard house AC electrical problems. The EM field is still read in each mode but it changes the way the meter interprets the information received.
- When doing an EVP (Electronic Voice Phenomena) session, place the meters near but not too close to the audio recorders. Make sure you log any changes in meter response that may correspond to a question asked. This way you can later sync this to any audio and video recordings that were made in the room at that time.
I hope this article has been helpful, please feel free to contact me if you have any questions regarding the article or about EM fields and EMF meters.