1 The type and scale of office chairs are related to the purpose or motive of sitting;
(2) The scales of office chairs must be matched with relative measurements of human body;
(3) The design of office chairs must provide adequate support and stability for the body sitting on it;
(4) The design of the office chair must make the person sitting on it change its posture;
(5) Backrest, especially in the waist support, can reduce the stress caused by the spine;
(6) The seat pad must have sufficient padding and proper hardness to help distribute the weight of the human body to the pressure of the sitting-bones nodule.
From the motive of sitting, the office chair can be divided into three types: rest chairs, work chairs, multi-purpose chairs.