In any electrical circuit, a current flows along a conductor, when a voltage or potential difference exists across the circuit. The voltage and the current create an electromagnetic field.
This electromagnetic field can be further broken down into:Electric Fields which are caused by the voltage difference between the conductor and the ground.
In the home, the intensity of the fields is usually low (2 to 3 volts/metre).
Power transmission lines are surrounded by very high electric fields (3,000 to 5,000 volts/metre). However, electric fields are relatively easy to shield, even vegetation will decrease the field to some extent.
Magnetic Fields which are created by current flowing. They travel through all materials and are often very difficult to shield, but can sometimes be diverted.
Observed Health Effects
Some of the observed health effects include:
- Childhood leukaemia
- Soft Tissue sarcomas
- Sleep disturbances
Research released in 2001 by the International Agency for Research into Cancer categorised magnetic fields of only 4 milligaus (mG) as "possibly carcinogenic".
Some sources of Electro Magnetic Fields (EMFs):
- Electrical wiring in houses and offices
- Power lines (transmission and distribution) lines
- Electricity meter boxes
- Electric blankets
- Banks of fluorescent lights - and low voltage lights - subject to wiring and ballasts
- Digital displays especially clock radios
- Neutral currents flowing though metal water pipes