NEC 2000 Series - Manual (Page 100)

A-6 Setting Up a Healthy Work Environment
Adjust Your Input Devices
Follow these points in positioning your keyboard and mouse.
T Position your keyboard directly in front of you. Avoid reaching when
using your keyboard or mouse.
T If you use a mouse, position it at the same height as the keyboard and
next to the keyboard. Keep your wrists straight and use your entire
arm when moving a mouse. Do not grasp the mouse tightly. Grasp the
mouse lightly and loosely.
T Adjust the keyboard height so that your elbows are near your body
and your forearms are parallel to the floor, with your forearms resting
on either armrests or forearm supports, in the manner described
previously. If you do not have armrests or forearm supports, your
upper arms should hang comfortably at your sides.
T Adjust your keyboard slope so that your wrists are straight while you
are typing.