One of the most frequent questions engineers ask before inspecting Lightning Protection System (LPS) & SPD Engineering Audit is: "Which standard should I cite on the certificate, and where do the pass/fail limits come from?" This reference guide maps IEC 62305-1/2/3/4 to national regulatory adoptions and provides the complete standard annex tables.
1. National & Regional Standard Equivalence Matrix
| Region / Language | Adopted National Standard & Regulatory Code |
|---|---|
| International / UK (EN) | IEC 62305-1/2/3/4 |
| Turkey (TR · Türkçe) | TS EN 62305-1..4 / İSG Ek-III Madde 2.3 |
| Germany / DACH (DE · Deutsch) | DIN EN 62305-1..4 (VDE 0185-305) |
| France (FR · Français) | NF EN 62305-1..4 / NF C 17-102 |
| Spain (ES · Español) | UNE-EN 62305-1..4 / CTE DB-SUA 8 |
| Italy (IT · Italiano) | CEI EN 62305-1..4 (CEI 81-10) |
| Gulf / Middle East (AR · العربية) | IEC 62305-1/2/3/4 / SASO / DEWA / ADDC |
2. Normative Acceptance Criteria & Mathematical Basis
Parametric IEC 62305-2/3/4 calculator: evaluates structure Equivalent Collection Area Ad & annual direct strike frequency ND, Rolling Sphere & Air-Termination Mast protection cone radius rp, perimeter down-conductor count, Separation Distance s = (ki x kc / km) x l, minimum earth electrode length l1 from soil resistivity rho, and SPD effective protection level Up/f.
Ad & ND: Ad = L·W + 6H(L+W) + 9·pi·H^2 | ND = Ng x Ad x 10^-6 — Equivalent collection area (m2) of isolated structure and expected direct lightning flashes per year (IEC 62305-2 Annex A).
rp (Mast Cone): rp = sqrt(h x (2r - h)) — Protected radius on horizontal plane for air-termination mast height h and rolling sphere radius r (IEC 62305-3 §5.2.2).
s (Separation): s = (ki x kc / km) x l — Minimum separation distance (m) to prevent dangerous sparking between LPS and internal metallic installations (IEC 62305-3 §6.3).
3. Official Standard Reference Tables
IEC 62305-3 Table 2 & Table 4: LPS Class Geometry & Separation Coefficients (IEC 62305-3 §5.2 & §6.3)
| LPS Class (LPL) | Peak Current I_max / I_min | Rolling Sphere Radius r | Max Mesh Size | Down-Conductor Spacing | Coefficient ki |
|---|---|---|---|---|---|
| Class I (LPL I) | 200 kA / 3 kA | r = 20 m | 5 x 5 m | 10 m | ki = 0.08 |
| Class II (LPL II) | 150 kA / 5 kA | r = 30 m | 10 x 10 m | 10 m | ki = 0.06 |
| Class III (LPL III) | 100 kA / 10 kA | r = 45 m | 15 x 15 m | 15 m | ki = 0.04 |
| Class IV (LPL IV) | 100 kA / 16 kA | r = 60 m | 20 x 20 m | 20 m | ki = 0.04 |
Note: Material factor km: Air = 1.0, Concrete / Brick / Wood = 0.5. Partitioning factor kc: 1 conductor = 1.0, 2 conductors = 0.66, 3+ conductors / mesh / ring earth = 0.44.