The HSE explains that hand-arm vibration (HAV) is a painful and disabling condition that affects the nerves, blood vessels, muscles and joints of the hands and arms. It causes tingling and numbness in the fingers, reduces grip strength and the sense of touch, and affects the blood circulation (vibration white finger, also known as VWF). It can be caused by operating hand-held power tools, such as road breakers; operating hand-guided equipment, such as powered lawnmowers; and holding materials being processed by hand-fed machines, such as pedestal grinders.