How Electromagnetic Fields (EMFs) affect us
Electromagnetic Fields (EMFs) Around Us
What Exactly is Electromagnetic Energy?
(EMFs) are force fields having both electric and magnetic components,
carrying a definite energy, and capable of producing an action at a distance
Electromagnetic radiation consists of two
An electrical field
(E-Field) – created by voltage (a
potential difference between two points)
and determines the
force with which electricity is pushed through an electrical pathway (e.g. a
wire, nerves, body’s meridians) to produce a current. E-Field strength is
measured in volts per meter (V/m).
E.g. A plugged-in, unlit lamp or
a charged battery has an electric field. An electric field varies with the
amount of the source voltage and decreases rapidly with the distance between
the two points.
A magnetic field (B-Field) –
electric current always produces an
expanding magnetic field
in addition to an electric field,
with lines of force at a 90-degree angle to the direction of current flow.
E.g. A lit lamp or an operating appliance has both an electric and
a magnetic field.
B-Field strength is
measured in amperes per meter (A/m).
E-Fields and B-Fields travel at right angles
to each other and at right angles to the direction of wave propagation. Together
they make up the total EMF. EMF strength indicates how many volts or amperes
the EMF will induce in a receiving antenna that is one meter long.
Currents changing direction produce EMFs which change direction
they vibrate) -
EM waves arise as a consequence of either one of the following two effects:
A changing electric field
If a current is fluctuating
(vibrating), E.g. alternating Current (AC),
the EM waves will fluctuate along with it. This changing field is
characterized by its rate of fluctuation or vibration, called its
frequency. Frequencies are
expressed in cycles per second or Hertz (Hz.)
A changing magnetic field –
induces a fluctuating current in an electrical
pathway, which in turn creates a changing electric field (see above).