The air-termination system intercepts the lightning flash. Designers must position air-termination networks using one of three standard-approved methods:
Each LPL correlates directly with a fixed set of minimum and maximum lightning current parameters used to design the physical system: Lightning Protection Level (LPL) Class of Matching LPS Maximum Current Parameter Minimum Current Parameter Calculated System Efficiency LPL II LPL III LPL IV
Electrical and telecommunication lines must be bonded via . While IEC 62305-3 dictates the placement of bonding bars, the detailed selection of SPDs falls under IEC 62305-4 . Separation Distance (
: This grounding network disperses the massive energy into the earth, with a typical target resistance of less than . Key Design Methods
Includes electrical continuity testing and ground resistance testing, typically executed every 2 to 4 years depending on the LPL. iec 62305-3 pdf
IEC 62305-3 includes several annexes and references that provide additional information and guidance:
The installation of external lightning protection (air-termination, down-conductor, and earth-termination systems).
Individual radial or vertical earth electrodes bonded to each down-conductor.
IEC 62305-3 is titled "Protection against lightning - Part 3: Physical damage to structures and life hazard." This standard specifically addresses the protection of structures against lightning strikes, focusing on the physical damage that can occur due to the strike itself and the subsequent effects like fires or explosions. The standard outlines measures to mitigate these risks, ensuring the safety of people and the integrity of structures. The air-termination system intercepts the lightning flash
The external LPS is designed to intercept direct lightning strikes, conduct the current safely to the earth, and disperse it into the ground. It consists of three main components. Air-Termination System
Edition 3 introduces a new term: Electrically Insulated Lightning Protection (EILP) . While technically similar to previous concepts, this official separation clarifies design and application, distinguishing it from a fully isolated LPS.
Lightning strikes present a severe threat to structures, human lives, and electronic systems. To mitigate these risks, the International Electrotechnical Commission developed the IEC 62305 standard series. Within this framework, focuses specifically on protecting structures against physical damage and guarding living beings against injury due to touch and step voltages.
IEC 62305-3 outlines the requirements for lightning protection systems both inside and outside a structure. The primary goals of this standard are: Separation Distance ( : This grounding network disperses
This classification is crucial because it dictates the geometry of your protection.
A grid of conductors laid across flat roof surfaces. The standard mandates maximum mesh dimensions based on the LPL (e.g., for Class I; for Class IV).
Unlike Part 2, which focuses on Risk Management (calculating whether you need protection), Part 3 assumes you need it and tells you how to do it. It provides the design principles for:
Engineering professionals, architects, and safety managers frequently search for the to design compliant Lightning Protection Systems (LPS). This article breaks down the core technical requirements, design methodologies, and protective measures detailed in the standard. 1. Scope and Core Objectives of IEC 62305-3