If ever there were any particular types of office chair that need to be especially comfortable it would be draughtsman and laboratory chairs. Most people are familiar with these stool height chairs that facilitate sitting behind tall tilted drafting tables. What you may not realize is that these chairs all have a very high center of gravity and as such can topple easily.
A quality draughtsman chair remedies the situation by having a wider than average five point base. In fact very often the bases of laboratory chairs are even weighted so as to provide further stability. Another important feature that is obviously needed for this type of chair is the foot ring that you will see on all of these chair designs. The foot ring must be adjustable so that as the height of the chair is increased the foot rest rises with it. Also because of the raised center of gravity seat backs on draughtsman chairs should not be allowed the risk of a tilting adjustment.