Electric and Magnetic Fields
Sources and Intensity
Choose a setting from the list to the left and move the person against the background to find out how strong the magnetic field is.
Alternative content
Glossary
EMFs
electric and magnetic fields
HV
high-voltage
kV
kilovolt (unit of measurement used for HV lines;
1 kV = 1 000 volts)
V/m
volt per metre (unit of measurement used for electric fields)
µT
microtesla (unit of measurement used for magnetic fields;
1 µT = 1 millionth of a tesla)
Magnetic Field Calculations
The height of overhead transmission lines varies considerably, depending on whether measurements are made near a tower (where lines are at their highest point) or mid-way between two towers (where lines are lowest). For this reason, magnetic field calculations are based on the conductors' average distance from the ground. Furthermore, for all types of lines, magnetic field strengths are measured at one metre from the ground.
For household appliances such as stoves, television sets and hair dryers, the magnetic field values are taken from Electric and Magnetic Fields Associated with the Use of Electric Power, Questions & Answers, published in June 2002 by the National Institute of Environmental Health Sciences.
