3 Things Every Building Must Have to Survive a Lightning Strike

3 Things Every Building Must Have to Survive a Lightning Strike

by Ohm Engineering Works | Sep 27, 2025 | Electric Company

Lightning is one of nature’s most powerful forces. In a fraction of a second, it can release energy strong enough to destroy structures, damage electrical systems, and put lives at risk. In India, where thunderstorms are frequent, lightning protection is often misunderstood.

Many people assume that placing a single metal rod (air rod) on top of a building will provide complete protection. In reality, this is not only incomplete but also unsafe. Effective lightning protection is a system, not a single component.

The Standard to Follow: IS/IEC 62305

Globally, the recognized standard for lightning protection is IEC 62305, adopted in India as IS/IEC 62305. This standard makes it clear: a lightning protection system (LPS) must be designed with multiple elements working together.

The Three Pillars of Lightning Protection

1. Air Terminals (Lightning Rods)

These are the “catchers” of the system. Instead of letting lightning strike a random part of the building, air terminals give it a safe and predictable point of contact.

2. Down Conductors

Once lightning is captured, the energy must travel quickly to the ground. Down conductors are thick, highly conductive paths that guide this energy safely downward, preventing it from jumping through walls or wiring.

3. Earthing (Grounding) System

Finally, the energy must be released into the earth. A low-resistance earthing system ensures the lightning current dissipates harmlessly. Without proper earthing, the energy may still damage equipment or cause dangerous step voltages near the building.

👉 Think of these three as a team: if one fails, the whole system is compromised.

Beyond Strikes: The Hidden Threat of Surges

Even when lightning does not directly strike a building, it can cause surges in the power supply. These sudden spikes in voltage travel through electrical networks and damage sensitive equipment like computers, control systems, and medical devices.

But here’s what most people don’t realize: surges don’t only come from lightning. Everyday grid operations—like switching heavy loads or faults in nearby lines—can also create harmful surges.

This is where Surge Protection Devices (SPDs) become essential.

The Layered Defense Approach with SPDs

To properly shield a building, SPDs must be installed in a tiered manner:

• Type 1+2 SPDs at the main supply point – These handle the biggest surges, including those from direct lightning currents.

• Type 2 SPDs at distribution panels – Provide secondary protection within the building.

• Type 3 SPDs at sensitive equipment – Act as the final line of defense for delicate loads like servers, lab instruments, or home electronics.

This multi-tiered setup ensures that no single surge, big or small, bypasses your protection.

Why This Matters

• A lightning strike lasts only a few millionths of a second, but the damage it causes can last years—from burned circuits to expensive equipment loss.

• A single failure in protection can result in safety hazards, downtime, and financial setbacks.

• Proper integration and testing of air terminals, down conductors, earthing, and SPDs ensure complete, reliable protection.

Conclusion

Lightning protection is not about “just a rod on the roof.” It is about creating a comprehensive shield that works silently in the background to safeguard lives, buildings, and technology.

By following IS/IEC 62305, and by adopting a layered SPD strategy, we move beyond outdated myths and build real, lasting safety for our infrastructure.

Lightning is powerful—but with the right system, it doesn’t have to be destructive.