The most common incident energy analysis methods, including equations, are located in NFPA 70E nonmandatory Informative Annex D.

• A. True
• B. False
• C. Not applicable
• D. Partially true

Answer: (A)

Arc-flash incident energy calculations rely on established methods that are documented in NFPA 70E’s Informative Annex D. This annex provides the commonly used approaches and the equations you apply to determine incident energy (in cal/cm2) at a worker’s location, based on system data such as voltage, available fault current, geometry, and clearing time. Although Annex D is nonmandatory, it is the primary reference for these calculations, describing methods like the IEEE 1584-based approaches and the simplified method, along with the step-by-step procedures and equations. This is why the statement is true: the most common incident energy analysis methods, including the equations, are located there.