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.
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.
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.
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)
