Assuming that live work is required, then it is becoming accepted that the method for quantifying the risk in the live working risk assessment needs to include at least an identification of the fault level at the work location, although better is to quantify the 'incident energy' or predicted energy level of any arc formed in the area.

The incident energy calculation includes factors to take account of arc impedance and expected distances both between conductors and between the arc and personnel. The IEEE 1584 standard has been aligned to reflect the actual results from real-life incidents in order to best capture the likely outcome of any fault although the calculations do not reflect the exact theoretical nature of the situation.

Industry accredited software is now available that allows an integrated approach to fault level, protection and arc flash incident energy calculation. SKM Systems Analysis Inc. 'Power Tools for Windows' allows the user to adjustments to the system (supply infeeds, closing bus-switches, changing protection settings etc.) and almost instantly see the impact on the Arc Flash hazard.

Shaw Power Limited are experienced users of 'Power Tools for Windows' for analysis on both low and high voltage systems to assess the fault levels and arc flash hazards in the systems. In addition, bespoke time/current curves for protection items not found in other software packages can be modelled using the curve creation facilities and this enables any protection device to be modelled and accurately analysed as long as a copy of the device time/current curve is available (this can be done through testing if required).