Whole-Body Vibration and International Standard ISO 2631: A Critique

The present International Standard for human response to whole-body vibration (ISO 2631) has been in effect since 1974. This standard is used to assess the effect of environmental vibration on operator health, efficiency, and comfort. This paper discusses the derivation of the standard and the bases upon which its main propositions were formed. Some aspects of the standard are supported by empirical data; however, this paper highlights a number of deficiencies that call into question the appropriateness of the standard for application. In particular, the shape of the frequency weighting curves, the concept of time dependency, the response criteria, and the weighting method for nonsinusoidal vibrations are examined in the light of published experimental findings.