Which of the following methods is recognized for selecting protective clothing within the arc flash boundary?

The selection of protective clothing within the arc flash boundary is primarily guided by incident energy analysis. This method involves calculating the potential energy that may be released during an arc flash event and determining the necessary protection levels for workers based on these calculations.

Incident energy analysis takes into account various factors including the available fault current, the duration of the fault, and the system configuration, which leads to a quantifiable measurement of energy (measured in calories per centimeter squared) that workers might be exposed to during an arc flash incident. This information is crucial in selecting appropriate personal protective equipment (PPE), including arc-rated clothing, to ensure that workers have sufficient protection against potential hazards.

Understanding the incident energy levels allows safety professionals to make informed decisions about the level of protection needed and ensures compliance with safety standards, thus minimizing injury risk in the event of an electrical arc flash incident. This method is widely accepted and is part of the NFPA 70E guidelines, making it the preferred approach for protective clothing selection within the arc flash boundary.