As far back as 1911, scientists associated vibration from hand-held tools with the risk of pain, numbing and blanching of the fingers, known as vibration white finger. But even now, many key aspects of the problem are not well understood, hampering efforts to identify worker populations at risk, and to design effective control measures.

NIOSH is pursuing studies to help fill those critical gaps and point to ways for effectively reducing risks of hand-vibration disorders for employees who use jackhammers, chipping hammers, power drills and other vibrating tools.

Using advanced microscope technologies, NIOSH will determine if adverse effects from vibrating tools can be predicted from physical changes in the capillaries at the base of the fingernail cuticle, too small to see with the naked eye.

Developing a computer model of stress and strain on the fingertips from vibrating tool handles, as measured by the degree to which the soft tissues of the fingertips are compressed or displaced by the vibrating handle, is another potential way to flag early warning of adverse effects.

For more info on NIOSH's hand-arm vibration research, contact Ren G. Dong, NIOSH Health Effects Laboratory Division,, or Aaron Schopper, NIOSH Health Effects Laboratory Division,