An ergonomic chair means that the seating matches both the person’s physical needs and job responsibilities so, to do this, it has to be adjustable.
Imagine the user – tall, short, thin, overweight, disabled in some way – adjustments need to be made to the ergonomic chair, to suit that particular worker.
The seat needs to be height-adjustable, both for leg length and body / back length. The chair should have an in-built lumbar support panel which, with adjustment, both height and tilt-wise, can be positioned to meet the person’s lumbar region and also support the natural curve of the spine. The seat itself will have a 16 to 20 inch height adjustment range, to make the average person’s feet comfortably touch the floor and pneumatic height adjustment allows for effortless change to the seat requirement. For people who have restricted growth, an ergonomic footstool will make feet to base contact successful, as the height of the chair needs to tally with the desk height.
The seat base itself should also allow for tilt and an ideal angle is for the front to slope downwards a little, as this takes any pressure off the knee joint area and thus supports continued good circulation in the lower legs. The seat density should not be too soft, as its purpose is to support your weight firmly and comfortably.
Arm height adjustment is also an ergonomic necessity, so support can be given to the lower arms, as they reach to meet the desk or keyboard. Getting this height right will go a long way to preventing hand / wrist problems, such as repetitive strain injury (RSI) and carpal tunnel syndrome. There is also an item called a wrist rest, a light-weight article which helps get that angle between wrist and keyboard right, again supporting joints and prolonging comfort.
Getting the chair right for the user will involve trial and error and, after a few days of usage, perfect settings can be reached, making sure that the ergonomic chair does what it is supposed to do. Consider, however, that after a holiday or a long period away from work, someone else may have made use of the chair, and possibly adjusted the settings.
Buying an ergonomic chair is an investment in both health and work performance. Sitting, with correct support given where it is needed, will make for a more comfortable and satisfying day of work.