Protecting your staff from arcing hazards

The characteristics and components of an arcing fault are described and the hazards caused by arcing faults are then listed in order of severity. Hazard control measures are then discussed in the order described in Table 1 of ANSI Z10. Designing the system to fail safely and separating the person from the energy are treated under the heading of eliminating the hazard. Installing arc contained switchgear, retiring old equipment and designing the system to be maintainable are considered under substituting less hazardous equipment. The engineering controls considered include; Displaying measured values remotely and taking into account the probability of the event. The main engineering control is carrying out the correct protection studies by calculating maximum and minimum fault currents for single-phase, two-phase-and-earth and three phase faults. It is necessary to ensure the protection works with arcing fault currents. The need for precision on warning and information labels is emphasized. Under administrative controls hazard assessments and the need to consider live work are discussed together with access control, work procedures and training. Finally PPE requirements are discussed..