Basics of Electric and Magnetic Fields
What are electric and magnetic fields?
Electric and magnetic fields (EMFs) are present wherever electricity flows — around appliances and powerlines, and in offices, schools and homes.
- Electric fields are invisible lines of force created by voltage. Voltage is the electric force that causes current in a conductor, and are shielded by most materials.
- Magnetic fields are invisible lines of force created by current, movement of electrons in a conductor. They are not shielded by most materials such as lead, soil and concrete.
- Electric fields are measured in volts per meter (V/m).
- Magnetic fields are measured in Gauss(G) or milligauss (mG) or Tesla (T) or microtesla (µT) units.
How are milligauss and microtesla related?
- 1 microtesla = 10 milligauss
- 1 Gauss = 1,000 milligauss
- 1 Tesla = 1,000,000 microtesla
Other EMF Properties
- Electric and magnetic field strengths diminish with distance.
- These fields are low energy, extremely low frequency (ELF) fields.
- They are not to be confused with high energy or ionizing radiation such as x-rays and gamma rays.