This part of 60027 gives general information about logarithmic and related quantities, and their units. Names and symbols for logarithmic quantities are given in other parts of IEC 60027, mainly in part 2, in the context where they belong.
DS/EN 60027-3:2007 history
2007DS/EN 60027-3:2007 Letter symbols to be used in electrical technology - Part 3: Logarithmic and related quantities, and their units