International Standard 2631 (1997) is concerned with the standardisation of the measurement, evaluation and assessment of whole-body vibration. With respect to health effects of whole-body vibration, the standard offers a combination of alternative methods so that different conclusions can be reached according to what is measured, how it is evaluated and how it is assessed. Various matters requiring consideration during a revision of the standard are suggested. The guidance for assessing the severity of whole-body vibration in ISO 2631 (1997) is compared with equivalent guidance for assessing hand-transmitted vibration in ISO 5349 (1986). It is suggested that when revising these standards some consideration should be given to the apparent contradictions suggesting that some exposures to whole-body vibration may be acceptable even though the same conditions would be considered unacceptable for hand-transmitted vibration.