Abstract:

Standards for vibration exposure promulgate different limits for hand--arm vibration (HAV) and for whole-body vibration (WBV). The discrepancy between the two should be explainable on some rational basis [Griffin, Handbook of Human Vibration (1990)], but there is no obvious difference in the mechanism of pathogenesis to the skin at each of the sites. The difference may arise because the endpoints chosen as the basis of each of the standards are different. One approach to estimating dose response [Jarabek, Toxicol. Lett. 79, 171--184 (1995)], characterizes the steps in developing a model as proceeding from a protective to a predictive paradigm as data progress from qualitative to quantitative. To develop vibration standards along this continuum, certain data must be developed: Among these are identification of performance effects of HAV, identification of long-term effects of WBV, and clarification of the impedance of the affected biological structures. Some of these areas have been addressed in recent revisions of ISO TC108/SC4 standards. Other activities will be proposed to further the evolution of human biodynamic assessment.