An arc flash study is an important part of electrical safety; the goal of which is to determine and manage risks that arise from arc flash events. These are electrical incidents in electrical environments and these are associated with high energy bursts, where life threatening cases may occur if right precautions are not taken. An arc flash study provides facilities and industries with valuable insight and helps construction workers to be safe on the job site.
The IEEE 1584 standard is a guideline that presents ways by which arc flash risk, incident energy and protection boundaries can be determined. By adhering to this standard, it is possible to make the right choices with regard to safety of various equipment, protective clothing and the working distances which are safe with the equipment.
The following guide outlines the key processes to follow while conducting an arc flash analysis using IEEE 1584.
1. State Specific Details of the System
A prerequisite to carrying out an arc flash analysis is to obtain accurate information about the electrical network. This includes information about all existing electrical equipment, including transformers, circuit breakers, panels and conductors. The data gathered should include voltages of the system, lengths of conductors, positions of equipment, and protection devices settings. Data measurements have to be precise because they make up the fundamental groundwork in any calculation needed and should depict actual system scenarios.
2. Identify System Modes and Operation Modes
The degree of an arc flash depends on system modes and operational conditions of a particular area. Possible configurations include the peak demand periods, normal state and other arrangements. Each of these conditions could alter the levels of arc flash energy, and studying these differences is crucial to developing a clear picture of existing risks. IEEE 1584 suggests that several analyses should be made in relation to system configuration and system load.
3. Perform Short-Circuit and Protective Device Coordination Studies
The next step for the arc flash analysis is to make a short-circuit study—trying to find fault currents available in different parts of the system. This information is important because higher fault currents are often associated with higher arc flash energy. A protective device coordination study is also necessary to identify the behavior of each device during fault conditions.
4. Calculate Incident Energy and Arc Flash Boundaries
IEEE 1584 offers computation techniques to estimate the level of energy at different distances from the fault initiation point. This information is very useful in demarcation of the arc flash protection distance, which is referred to as the arc flash protection boundary. Those working within this boundary are exposed to arc flash and must wear recommended personal protective equipment (PPE).
5. Selecting the Right Personal Protective Equipment (PPE) and Labeling Equipment
Identify the personal protective equipment needed by persons operating in the arc flash limit. Every energy level entails different categories of PPE so that the workers are well protected from any type of injury. It is also important to label the equipment appropriately with arc flash hazard information. Tags should describe the incident energy level, the necessary personal protective equipment, and the arc flash hazard range, to encourage appropriate behavior.
