Which standards apply in Bangladesh?

We design to IEC 62305 and NFPA 780, with BS EN 62305 as the harmonised reference.

Do I need a risk assessment first?

Yes — IEC 62305 design always starts from a structure-specific risk assessment.

Knowledge

IEC 62305 Lightning Protection System Design — A Bangladesh Guide

Sustech Engineering Team · 18/05/2026

How a standards-based lightning protection system is designed under IEC 62305 — risk assessment, protection levels and components.

Start with a risk assessment

IEC 62305 design begins with a risk assessment of the structure and its contents — location, dimensions, occupancy, services and the consequences of a strike. The assessment determines the required Lightning Protection Level (LPL I–IV) and whether protection is needed at all.

Air termination, down-conductors and earthing

The system comprises an air-termination network (rods, meshes or catenaries sized by the rolling-sphere method), down-conductors that route the current safely to ground, and a low-impedance earth-termination system. Bonding and surge protection (SPDs) protect internal systems.

Soil resistivity and earthing

Effective earthing depends on soil resistivity, which we measure with the Wenner four-pin method. Electrode design (rods, plates or rings) is then chosen to achieve a low, stable earth resistance suitable for the protection level.

FAQ

Which standards apply in Bangladesh?: We design to IEC 62305 and NFPA 780, with BS EN 62305 as the harmonised reference.
Do I need a risk assessment first?: Yes — IEC 62305 design always starts from a structure-specific risk assessment.