Published at Saturday, October 26th 2019, 22:15:53 PM by Sinta Sinta. Chair. On some chairs, the user can adjust the height, while on other chairs the height is fixed. Some chairs allow the user to recline backward or to adjust and fix the back support angle. Think about the tasks performed by the employee who will be using the chair. For example, those typing on keyboard should always be provided with armrests.