Establishing a compartment fire's area of origin when it has been burning at postflashover conditions is a difficult process. Burn patterns traditionally used by fire investigators following post-flashover fires can be erroneous. This research has looked into the reliability of using the electrical wiring in a building to establish the origin of a fire. Sixty five fully furnished experimental compartment fires were used and the resultant artefacts analysed with various types of microscopy. Nine separate categories of localised metallic "arcing damage" were identified following the experiments. The surface elemental characteristics of the artefacts were analysed and an association was established between the electrical copper conductors and the materials used to fix the electrical wiring to a surface. This research has demonstrated the importance of a clear demarcation area between the localised metallic damage of the conductors and the undamaged area, to determine whether or not localised melting of electrical conductors is due to electrical arcing damage. Correlations were found within the data collected from the experiments that linked the time to arcing events, the approximate temperature at which these events occurred and the circuit protection device operation sequence. No other correlations were revealed. The analysis of the three-dimensional data has indicated that there is a high probability of arcing damage to electrical conductors occurring close to a fire's area of origin. The series of experimental fires with repeated scenarios has validated the reliability of the arc fault mapping methodology.