Divide the measurement of the intensity of the electromagnetic field, also called the power density, given in milliwatts per square meter (mW/m^2) by 1000 to convert from mW/m^2 to the more traditional power density units of watts per square meter (W/m^2). For example, a power density of 5 mW/m^2 is equivalent to 0.005 W/m^2.
Divide the power density given in W/m^2 by the electric field strength measurement given in volts per meter (V/m). The quotient is the equivalent of the magnetic field strength and has the units of amps per meter (A/m).
Multiply the magnetic field strength given in A/m by 1000 to obtain the field strength in milliamps per meter (mA/m).