Simplified IEC Risk Assessment Calculator (SIRAC): A Complete Guide to Compliance and Implementation
The physical footprint of the building dictates its "equivalent collection area"—the mathematical space around a building where a lightning flash is likely to hit the structure rather than the flat ground. , Width ( ) , and Height ( ) of the roof plane.
The is a specialized software tool originally introduced by the International Electrotechnical Commission (IEC) to streamline complex lightning protection calculations. It was first presented in Annex J of the 2006 edition of IEC 62305-2 , the international standard for lightning risk management. What is SIRAC? simplified iec risk assessment calculator sirac
To appreciate the utility of SIRAC, one must understand the underlying standard it simplifies. IEC 62305-2 evaluates risk by identifying four primary types of loss: : Loss of human life (including permanent injury).
) value is assigned by national authorities. SIRAC calculates the actual risk ( It was first presented in Annex J of
The Simplified IEC Risk Assessment Calculator (SIRAC) played a crucial role in the history of electrical safety standards. As an official tool provided by the IEC, it succeeded in its mission to make complex risk calculations more accessible, speeding up the adoption of IEC 62305-2 worldwide. While it has been removed from current editions and is no longer considered a compliant tool for new projects, its legacy as a pioneer in user-friendly safety software is secure.
Use SIRAC to start the conversation. Use it to screen risks. Use it to prioritize which loops need a full-blown LOPA. But never, ever use it as the final signature on the certificate of life safety. IEC 62305-2 evaluates risk by identifying four primary
Despite its limitations, SiRAC was successfully used to assess lightning risk for various real-world projects. These applications demonstrate its utility in facilitating IEC 62305-2 compliance. One documented use was for a laboratory building at a technical university in Rijeka. The engineer used SiRAC to perform a risk assessment based on HRN EN 62305-2 (the Croatian national adoption of the standard). The results showed that the laboratory, equipped with a Level IV Lightning Protection System (LPS), met the required safety standards.
The calculator simplifies the risk assessment process by focusing on typical, non-complex structures. Key capabilities include: