What is the incident energy level that defines the arc flash boundary?

The incident energy level that defines the arc flash boundary is 1.2 cal/cm². This level is significant because it marks the point at which the thermal energy from an arc flash is sufficient to cause a second-degree burn to a person. Establishing this boundary helps to ensure that workers maintain a safe distance from potential arc flash hazards.

Understanding the importance of the arc flash boundary is crucial in electrical safety practices, as it guides the implementation of appropriate personal protective equipment (PPE) and safety measures during work on or near energized electrical equipment. This boundary is a critical element in the risk assessment process for electrical work, helping to protect individuals from serious injuries. Thus, recognizing 1.2 cal/cm² as the threshold for the arc flash boundary is essential for maintaining safety standards in electrical environments.