For the purposes of this Directive, the following terms shall mean:

1. (a)

   ‘hand-arm vibration’: the mechanical vibration that, when transmitted to the human hand-arm system, entails risks to the health and safety of workers, in particular vascular, bone or joint, neurological or muscular disorders;

2. (b)

   ‘whole-body vibration’: the mechanical vibration that, when transmitted to the whole body, entails risks to the health and safety of workers, in particular lower-back morbidity and trauma of the spine.