EMF stands for Electro Magnetic Fields which are emitted by man made sources and may be recorded on meters which are capable of detecting them.
Most EMF Meters are calibrated to measure the frequency of European and US mains electricity although there are some which are capable of measuring much lower frequencies. The meters were originally created to help ease the concerns of those concerned with Electro Magnetic Radiation (EMR) emissions which are caused by cell phones, clock radios, power lines etc., in or around their properties, also known as radio frequency (RF) but were also found to be useful by paranormal investigators to take environmental readings during investigations.
The following videos explore the use of EMF meters by Ghost Hunters
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