| LPL | Peak current (kA) | Rolling sphere radius (m) | Mesh size (m) | |------|------------------|---------------------------|---------------| | I | 200 (minimum 3) | 20 | 5 × 5 | | II | 150 (min 5) | 30 | 10 × 10 | | III | 100 (min 10) | 45 | 15 × 15 | | IV | 100 (min 16) | 60 | 20 × 20 |
:
For an isolated rectangular building:
[ V_touch = \fracI \cdot \rho2 \pi \left( \frac1a - \frac1r \right) ] lightning protection calculation
[ n = \fracPd ]
[ R = N \times P \times L ]