Prevention through design: Reducing risks near service and main disconnects

A common practice is to install a service disconnect or a main disconnect for a feeder system in the same enclosure compartment as the downstream overcurrent protective devices. This can result in potential safety risks of shock and arc flash. This paper addresses the advantages and disadvantages of isolating a service disconnect for electrical service for industrial and commercial installations from the perspective of prevention through design. The paper compares shock and arc flash hazard for both cases when the service disconnect or a main breaker is isolated and when it is in the same enclosure.