The aggregation principles of IEC 61000-4-30 is a well-known concept implemented in Power Quality (PQ) recorders. Only rms data is retained. Harmonic emission assessment requires the analysis of harmonic phasors. Continuous measurement of harmonic phasors is constrained by the volume of data resulting if the measurement period is longer. An innovative approach to also aggregate harmonic phase angles has been introduced and this paper evaluates how the aggregation interval affect the application of this concept in harmonic emission. Two different types of harmonic emission sources are evaluated in a distribution network. Results from this field data are used to demonstrate that although it is not possible to use a standard aggregation interval as in the IEC 61000-4-30, that the concept of aggregating harmonic phasors present an improved understanding of harmonic emission.