IEC 60721-2-6:2022

Overview

IEC 60721-2-6:2022 is an international standard published by the International Electrotechnical Commission (IEC) that classifies environmental conditions related to earthquake vibration and shock. This standard forms part 2-6 of the IEC 60721 series, which addresses environmental conditions appearing in nature. The primary scope of IEC 60721-2-6:2022 is to define fundamental properties and quantities for characterizing earthquake effects on products during storage and use, specifically focusing on ground surface conditions.

The second edition of this standard replaces the 1990 edition, providing a technical revision that reflects up-to-date seismic classification practices. It introduces seismic activity zone classifications relevant for equipment installation locations, updated intensity and magnitude scales, and practical guidance on retrieving peak ground acceleration (PGA) data worldwide. It also highlights the importance of adhering to national standards and legal requirements related to seismic conditions.

Key Topics

• Seismic Environment and Earthquake Behavior
  The standard details the origin and propagation of earthquakes, including seismic waves and their impact on products. It discusses how earthquake vibrations can be modeled as stochastic processes affecting equipment reliability and safety.

• Earthquake Scales and Classification
  Updated scales for earthquake intensity and magnitude are provided, aiding in the assessment of seismic exposure severity. The correlation between intensity, magnitude, and peak ground acceleration has been removed due to scientific uncertainties, ensuring conservative and reliable application.

• Seismic Activity Zones
  A classification system categorizes seismic activity levels into a limited number of classes, assisting manufacturers and users in understanding potential earthquake risks at specific installation sites. An informative annex guides users on how to access consistent global peak ground acceleration data, replacing previous less practical zone maps.

• Response Spectra
  The standard introduces response spectra concepts for describing seismic environments, including ground response spectra and required response spectra for equipment qualification.

• Guidance on National Regulations
  IEC 60721-2-6:2022 emphasizes awareness of national standards and legal frameworks that may supersede or complement the seismic classification provided, promoting compliance and safety.

Applications

• Product Design and Testing
  Manufacturers of electrical, electronic, and electromechanical equipment use IEC 60721-2-6:2022 to determine the seismic conditions products may encounter during storage and operation. This ensures products are designed and tested to withstand relevant earthquake vibrations and shocks.

• Seismic Risk Assessment
  Facilities and infrastructure planners apply the seismic activity classifications to evaluate the earthquake risk of installation sites, supporting safety and reliability strategies for critical systems.

• Standardized Qualification Procedures
  The standard serves as a reference for establishing environmental testing criteria in compliance with seismic conditions, aligning with IEC 60068-3-3 for seismic test methods on equipment.

• Regulatory Compliance
  Compliance with IEC 60721-2-6:2022 supports adherence to international best practices and can facilitate conformity with national earthquake-related regulations and building codes.

Related Standards

• IEC 60721-1 – Classification of Environmental Parameters and Their Severities
  Lays foundational concepts on environmental parameters affecting products.

• IEC 60721-3 – Classification of Groups of Environmental Parameters and Their Severities
  Extends the classification framework utilized by part 2-6.

• IEC 60068-3-3:2019 – Environmental Testing – Seismic Test Methods for Equipment
  Specifies seismic test methods complementing the environmental classification of IEC 60721-2-6.

• ISO 2041 – Mechanical Vibration, Shock, and Condition Monitoring – Vocabulary
  Defines terminology relevant to vibration and shock consistent with the standard’s terms.

Summary

IEC 60721-2-6:2022 provides a robust framework for classifying earthquake-related environmental conditions impacting electrical and electronic products. By defining seismic activity zones and updated seismic scales, it supports product safety, design optimization, and regulatory compliance internationally. The standard’s practical guidance on seismic data retrieval and emphasis on national requirements ensure its applicability in diverse geographical contexts, making it a vital resource for industries affected by seismic risks.

Keywords: IEC 60721-2-6, earthquake vibration, earthquake shock, seismic classification, environmental conditions, peak ground acceleration, seismic activity zones, equipment testing, seismic risk assessment, IEC standards, seismic test methods, environmental testing