ISO 9688:1990

Overview

ISO 9688:1990 is an international standard developed by the International Organization for Standardization (ISO) that provides analytical methods for assessing the shock resistance of mechanical systems. It focuses on establishing clear procedures for specifying analytical approaches, conducting shock resistance analyses, and ensuring effective information exchange between suppliers and users of such analyses. This standard applies broadly to products-including equipment, components, machines, vehicles, or structures-as well as human subjects when assessing shock resistance is necessary.

The core purpose of ISO 9688:1990 is to create a technical dialogue framework between clients requesting shock resistance evaluations and the suppliers conducting analytical assessments based on computational methods. While physical shock testing remains important, analytical methods offer a valuable alternative when practical testing is impossible, costly, or impractical.

Key Topics

• Scope and Applicability ISO 9688:1990 covers procedures for defining analytical methods and protocols for shock resistance evaluation. It applies to any mechanical system or human subject where an analytical shock assessment is needed. The standard emphasizes that it does not define numerical values for shock environments or acceptability levels but focuses on the process and information exchange.

• Information Exchange Protocol The standard specifies essential information to be shared by the user (client) with the supplier (analyst), including:

  • Mechanical properties of the product and environment (dimensions, material, construction, mounting).
  • Shock input parameters and tolerance criteria.
  • Appropriate mathematical model selection reflecting the product's physical behavior.
  • Analysis methods, frequency ranges, and expected results presentation.

• Analytical Methods ISO 9688 recognizes various analytical approaches depending on the complexity and function of the system:

  • Simple static equivalent load analysis (e.g., g-load equivalent).
  • Models using elastic or plastic deformation characteristics to measure energy absorption capacity.
  • Advanced methods including temporal variation analysis, finite element modeling, and analytical modal analysis.

• Definitions and Concepts The standard draws on definitions from ISO 2041:1990 related to vibrations and shocks, including terms such as shock resistance, shock signals, modal analysis, impact, shock duration, and shock spectrum. Understanding these terms is crucial for accurate communication and consistent analysis.

Applications

ISO 9688:1990 is applied in industries and contexts where shock resistance evaluation is critical but physical shock testing is constrained by size, cost, or testing feasibility. Typical applications include:

• Product Design and Development Supporting design decisions by modeling expected shock environments, optimizing shock insulation or fixation systems, and predicting product behavior under shock loading before physical prototypes are tested.

• Test Planning Providing an analytical basis for planning physical shock testing, including deciding whether testing is necessary or defining relevant test parameters.

• Safety and Reliability Assessments Assessing mechanical systems such as vehicles, machinery, structural components, and protective equipment for compliance with safety and performance standards involving mechanical shock exposure.

• Human Factors Engineering Evaluating shock exposure impacts on human subjects in occupational, automotive, or aerospace environments, contributing to ergonomic design and health protection.

Related Standards

ISO 9688:1990 works in conjunction with multiple other international standards relevant to mechanical vibration and shock:

• ISO 2041:1990 - Vibration and shock vocabulary, providing standardized terminologies crucial for consistent communication in shock resistance analysis.
• IEC 68-2-27 - Environmental testing protocols for mechanical shock, aimed at standardizing physical shock testing methods.
• ISO 8568:1989 - Standard specifications for shock testing machines, outlining performance and characteristics of equipment used for mechanical shock tests.

These standards collectively support rigorous, harmonized practices in shock testing and analysis, promoting safety, reliability, and quality across mechanical systems worldwide.

Keywords: ISO 9688, shock resistance, mechanical vibration, mechanical shock analysis, analytical methods, mechanical systems, shock testing, finite element analysis, modal analysis, product reliability, safety assessment, mechanical design standards, ISO standards.