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Lightning Protection & Risk Assessment Calculator

IEC 62305-1/2 risk assessment — collection area, structure risk (RA + RB) and minimum LPS class. Connected-line risk (RU/RV) and SPD/LEMP protection sizing are subscriber features.

AAJappsEngineering Calculation Report

Lightning Protection & Risk Assessment Calculator

IEC 62305-1/2

Generated

For preliminary engineering use only — always verify results against project-specific standards and a qualified engineer's review before use in a real design.

Structure & environment

/km²/yr
m
m
m

Loss factors (R_A / R_B, Table C.2/C.3 style)

h/yr

Connected line risk (RU / RV)

Subscriber
m
m

SPD / LEMP protection (Annex D)

Subscriber
Not yet implemented in this calculator — the effective protection level (Upf) vs. equipment withstand (Uw) and induction-distance (loc/lpi) checks from IEC 62305-2 Annex D haven't been built yet. R1 above (including the connected-line RU/RV terms) doesn't depend on this section.

Collection area & flash frequency

Collection Area (Ad)2577.9 m²
Flash Frequency (Nd)1.031e-2 /year

Risk R1 (loss of human life)

R_A (touch/step)1.031e-9
R_B (physical damage)1.031e-6
R_U / R_V (connected lines)2.400e-8 / 2.400e-5
R1 vs Tolerable (RT = 1×10⁻⁵)2.506e-5 ✗

Minimum LPS class required

ClassClass I insufficient — reduce risk further
Rolling Sphere Radius—
Mesh Size—
Down Conductor Spacing—