Conventional drawing boards in design offices have mostly been replaced by CAD workstations. However some of them do still exist.
Conventional design work requires elevated illuminance levels of 750 lx on a plane, e.g. inclined by 75% from the horizontal. This illuminance corresponds to a horizontal illuminance Eh of about 1.500 lx. Furthermore, good uniformity, shadow detail and plenty of daylight is required on the drawing board.
Regarding daylight and high illuminance, such conventional design workstations differ significantly from CAD workstations, where illuminance as well as daylight are distinctly reduced.
The (conventional) design office is illuminated by continuous lines composed of suspended direct-indirect-distribution specular louvre luminaires parallel to the windows.