Arc-Flash Incident-Energy Screen (Lee 1982)

Simplified pre-IEEE-1584 incident-energy estimate and PPE band. Screen only; not an IEEE 1584 study.

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Formula and source

E_lee (cal/cm^2 at distance D in inches) = (2.142e6 * V * I_bf * t) / D^2. Boundary distance D_b = sqrt((2.142e6 * V * I_bf * t) / 1.2). PPE category band looked up against the NFPA 70E Table 130.7(C)(15)(c) ranges (table cited by name only; not reproduced).

NFPA 70E-2024 ยง130.5 governs the arc-flash risk assessment. IEEE 1584-2018 is the study-grade method.

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