Sofa Ergonomics & Anthropometrics

According to Allsteel’s Ergonomics and Design Reference Guide, anthropometrics (anthropos = human; metron = measure) is “the scientific study of the measurements and proportions of the human body” as well as the differences between individuals and groups. Anthropometrics is an important first step in designing or choosing a living room sofa which is best for you and any family or guests who may use it.

Anthropometrics uses a percentile range with most furniture being designed to suit everyone from the 5th percentile to the 95th percentile. This means that “the 5th% female value for a particular dimension (e.g. sitting height) usually represents the smallest measurement for design in a population. Conversely, a 95th% male value may represent the largest dimension for which one is designing.

The Ergonomics and Design reference Guide explains that "the 5th% to 95th% range accommodates approximately 90% of the population.”

Ergonomics (from the Greek ergo meaning work and nomos meaning laws) is the “science focused on the study of human fit, and decreased fatigue and discomfort through product design” explains Allsteel. Ergonomics can only exist by understanding the rules of anthropometrics.

The Furniture Industry Research Authority also explains, “Ergonomics is the application of scientific information concerning humans to the design of objects, systems and environment for human use. Ergonomics comes into everything which involves people. Work systems, sports and leisure, health and safety should all embody ergonomics principles if well designed.”

Ergonomics is vastly important in furniture design, particularly chair and sofa design. (It has been said that chair design is the “acid test” for designers.) That's because sitting for extended periods of time affects our bodies dramatically. The pressure is channeled downwards which puts a lot of strain on our lower backs leading to back pain, body aches and overall muscle fatigue. Blood flow is also affected. Poor posture whilst sitting may also cause the discs in the spine to compress and hip flexors to become short and tight, limiting their range of motion.

So it’s no surprise that what we choose to sit in is of major consequence. Your choice will directly impact your health and the health of your family and guests. Finding the most ergonomic sofa you can find is the goal. Convinced yet?

Place your sofa facing the direction you intend to focus the sitter’s attention. If the purpose of your formal seating arrangement is to encourage conversation, have the sofa face the other sofa or armchairs and try not to have too many seats off centre.

Similarly, if the sofa is one which the family sits in to watch TV, position it facing and central to the TV and at an appropriate distance. Offsetting it, setting it at an angle or having it too close to the TV, will result in neck straining and twisting which are detrimental to back and neck health.