Based on IEC Corporation’s successful arc flash analysis for the City of Pasadena’s older power facility (at units GT1 & GT2), the City requested that IEC again support the City in conducting an arc flash analysis at its newer facility for the GT3 & GT4 LM6000 units. IEC evaluated Units GT3 & GT4 electrical systems from the point of interconnection with the grid to the 480V motor control centers. The detailed arc flash calculations were generated using SKM Power Tools version 220.127.116.11 modeling software. Equipment data and settings for the plant modeling were collected and supplied by plant personnel. Short circuit currents were calculated at the 34KV, 13.8KV, 4.16KV, and 480V buses and then used to calculate the arc flash energy and boundary at the various bus voltages. The duration of the arc flash current was based on existing fuses, breakers and relays settings. The results of the arc flash study were provided in a complete report that identified the hazard potential according to the arc flash regulations of NFPA 70E (Standard for Electrical Safety in the Workplace) and IEEE 1584 (Guide for Performing Arc-Flash Hazard Calculations). The results detailed requirements for the proper Personal Protective Equipment (PPE) that must be worn by qualified personnel to operate and work on live electrical equipment. IEC also recommended several next steps to the City of Pasadena to consider as a result of the study.