Units used for measuring EMFs

Electric Fields

Electric fields are usually measured in volts per metre (V/m)

  • Multiple is used for large fields: 1 kilovolt per metre (kV/m) = 1000 volts per metre


Magnetic Fields

Magnetic fields are usually measured in microteslas (µT)

  • Multiple used for large fields: 1 millitesla = 1000 microteslas
    or small fields: 1 nanotesla = 0.001 microteslas

Other units are sometimes used:

  • 1 milligauss = 0.1 microteslas (milligauss is common in the USA)
  • 1 ampere per metre = 1.25 microteslas
    (this conversion for amperes per metre is only true for air and other non-magnetic materials. It changes in the pressure of magnectic materials such as iron.)

The following chart shows how to convert between the different units used for magnetic fields:

diagram showing how to convert between units