Evaluating Task Seating

Despite all the options and available adjustments, learn 

how to make an informed decision on task seating

To most ergonomists and health and safety officers, a well-designed task chair is 
considered to be one of the most important components of an ergonomic workstation.
But, with so many types of task chairs available today, how should you make an informed 
decision when the time comes to make a purchase? What types of adjustments are 
critical for maintaining the health and  comfort of computer users? These are among the 
most common questions being raised by today’s facility managers with respect to
evaluating task seating. 

To begin, consider the functional goals of a task chair.

A well-designed chair should offer sufficient adjustability to accommodate at least 90
 percent of the working population (the chair should fit a fifth-percentile female through
a 95th-percentile male). Chairs that offer adjustable seat height, seat pan depth,
backrest height/lumbar support, and armrest height are often successful in 
accommodating most users if they adjust within recommended adjustment
 ranges (see sidebar). Adjustments beyond those mentioned often complicate the
 operation of the chair and have received little, if any, validation from an ergonomics
 perspective.

EVOLUTION OF TASK SEATING 

A chair should promote movement of the spine. Fixed, upright postures, no matter

how close to optimal, will generate static muscle contractions and subsequent
discomfort. Spinal discs lack a direct blood supply and are nourished through 
osmosis, a process that is best facilitated through movement. It is critical, 
therefore, that the backrest allows a person to move freely throughout a range of
supported postures. This concept is often referred to as “dynamic sitting.”
Difficult-to-adjust tension-control knobs and back locks are barriers to movement 
and can complicate the ergonomic operation of the chair. Today’s newer chairs 
are equipped with self-adjusting recline mechanisms that automatically adjust 
the amount of backrest tension  based on body weight. This technology dramatically
simplifies the operation of the chair while maintaining a user’s spinal health and comfort.

A well-designed chair must be intuitive to use. Chairs of the ‘80s and ‘90s became so 
complicated to adjust that few users could correctly identify a single chair adjustment. A 1995 
study conducted by Martin Helander, a renowned professor of ergonomics at Nanyang 
Technological University in Singapore, found that less than 2 percent of the population surveyed 
was able to correctly identify the purpose of the tension-control knob. All adjustments should be 
possible while the user is sitting in the chair. The controls should be positioned within reach and
 should never require excessive force to operate.

The biggest mistake facility managers tend to make when evaluating task seating is to allow
 employees to make decisions based on short-term usage. Decisions in this case are more likely
 to be made based on the aesthetics of the chair rather than on the comfort of the chair. Workers
 should be given an opportunity to compare each chair over a period of several days.

At Humanscale, we believe that the highest level of functionality is achieved through simplicity. 
With our ergonomic home and office chairs, we replace heavy, complex mechanisms with the 
sitter’s own body weight and the laws of physics to encourage movement, providing the most
 comfortable chair available.

Contact Us

For More Information: https://scube-ergo.com/

Email – humanscale.india@scube-ergo.in

Bangalore: +91 88613 02352 (Sathish)

Hyderabad: +91 9885051419 (Sandeep)

Mumbai: +91 9742329159 (Ravi)