Historical
IEC 60250 Ed. 1.0 b:1969
Recommended methods for the determination of the permittivity and dielectric dissipation factor of electrical insulating materials at power, audio and radio frequencies including metre wavelengths
Procedures for the determination of permittivity and dissipation factor and of quantities calculated from them, such as loss index, within the frequency range 15Hz to 300 MHz approximately.
International Electrotechnical Commission [iec]