In Part 2 of Ergonomics Essentials by Buzz Furniture in Melbourne, we go through the ins and outs of how to find the perfect ergonomic office chair for you. As mentioned in Part 1, ergonomics in office furniture simply involves matching office equipment to the user and the task to the worker. Ergonomic furniture has the ultimate aim of providing a more comfortable, safer, and more efficient working environment.
Why is an ergonomic office chair so important?
It is quite common for the humble office chair to be overlooked. For example, during the whole 6 years of my studies at university, I sat on the same cheap office chair. This chair was heavy to move around, half the wheels stopped working, and the the height adjustment on the seat did not lock properly so I often found myself craning my neck to see my laptop screen as my chair sunk slowly to its lowest height.
I upgraded this chair after my studies, but it wasn’t until I began to be interested in office furniture that I started learning about all the long-term damage that spending all those hours in that dingy chair could have done. For example, I developed a constant sore lower back from leaning forward constantly to reach my desk as the wheels on my chair were broken.
I also developed a very stiff neck (which I can still crack ferociously at will to this day) from craning my head forward into my laptop screen. Not only that, both the cheap quality and the style of the foam padding in the seat would make my buttocks sore after long periods of sitting, as well as cut off the circulation below my knees so that I would constantly cramp or get a dead leg after a long work period.
While this example is somewhat extreme and businesses tend to have more expendable income than a university student, it is still surprising to see that the ‘any chair will do’ mentality still exists in many workplaces today. If you think about it, the office chair could very well be the most used single piece of furniture that you use every day, for a lot of people even more than their own bed. And people invest a lot of money in their beds. In fact, the major American office furniture company Herman Miller observed and catalogued the movements of 40 random office workers and found that they spent approximately 93% of their time sitting in an office chair.
Features of an Ergonomic Office Chair
The term ‘ergonomics’ derives from the Greek words: Ergon (‘work’) and Nomics (‘natural law’). This term suggests that ergonomic office furniture might then consider a range of factors that help the ‘natural’ workings of things so that performance is increased. Ergonomic considerations include:
- Physical factors such as ambient conditions and physical objects
- Biological factors like body dimensions and capabilities, and physiological processes
- Psychological factors such as mental workload, information processing, motivation, and training
- Work factors such as job demands and job design
- Organisational factors like organisational climate and management regimes
Because of the enormous variety of factors that an office chair has to account for, the ideal ergonomic office chair should be adjustable in a variety of ways. Features might include:
- Adjustable seat height
- Lumbar support on backrest
- Adjustable backrest height
- Adjustable backrest tilt
- Adjustable seat pan tilt
- Rounded front edge of seat
- Adjustment controls that are easy to operate from the seated position
- Seat pan depth adjustment
- Five-point base
- Comfortable cushioning and covering on the seat and backrest
While stock standard ergonomic chairs suits the majority of users, there will be times when employees require even more specialised seating. Buzz Furniture Melbourne accommodates for a range of custom adjustments and specific seating features. These might include:
- Seat pans with greater/ smaller depths for taller/ shorter workers
- Seat pans with greater widths for workers with wider hips
- Seat height adjustments with greater height for very tall workers
- Chairs designed to tolerate high loading for large or heavy workers
- Chairs designed for greater than 8 hr shift use
Let’s take a more in-depth look at different parts of an office chair, specifically and back and armrests. Worksafe Queensland has a great guide for ergonomic chairs, which you can read in detail here.
The backrest of any office chair should be able to support the upper and lower back and be height adjustable. This is so the lumbar support on the backrest fits well against the natural curvature of the lower back.
Backrests can also be tilt adjustable, so that they can move forwards and backwards. It has been determined that an angle of 100 to 120 degrees between the trunk and thighs encourages better spinal posture. This angle can be achieved by adjusting both the backrest angle as well as the seat pan tilt if this is available.
Highly sedentary jobs might benefit from ‘free-floating’ back support mechanisms that are incorporated into the backrest. This allows the backrest to move through a pre-set range as the worker’s back moves. The user can then move through a range of acceptable postures while still remaining in a supported seated position.
Most office chairs can be purchased with or without armrests. When buying new chairs, consideration should be given to the design and actual need for armrests. Armrests offer foreatm support and help employees to rise and lower themselves into the chair. Forearms should be able to rest comfortably on the armrests, with the shoulders relaxed.
When purchasing chairs with armrests, buyers should be ensuring that the armrests are height adjustable and can be turned inwards and outwards. There are certain situations when armrests do not encourage ergonomics and should either not be purchased with the chair or removed from an office chair. These situations include:
- If they prevent the user from getting close to the desk and at a comfortable distance from the keyboard and screen.
- If they interfere with using input devices such as a keyboard or mouse
- If they prevent the user from turning or getting up from the chair easily
- If they are not adjustable
- If they result in the back bending sideways when leaning on the armrest, which means that the armrests are too low for the user.
Researchers at Herman Miller found that office workers made on average 53 changes in their posture per hour at their chair, as well as over 180 changes in their arm position per hour. While this sounds like a lot, you have to take into account that when making a phone call for example, people will play with something on their desk, or doodle on a notepad. When writing or typing they can lean on an elbow, lean forwards and backwards in their chair. In meetings, people often fidget, squirm, twist, or turn.
And even though you may have not considered it, people sitting in office chairs use various conscious and unconscious strategues to shift activity away from their tiring muscles. Have you ever shaken out your hands, changed to doing another task, or started stretching because you were tired of being in the same position? Or better still, have you suddenly felt the urge to get up from your chair and get a coffee, or make some photocopies?
Needless to say, there are almost an infinite number of ergonomic office chairs on the market for buyers to choose from. When considering a chair change, purchasers should look to good office furniture companies when seeking professional advice. This way the right range of chairs can be selected that suit your company’s budget, tasks, and style. At Buzz Furniture, all our clients get the option of trialing our great range of ergonomic chairs when deciding on the right one. Simply discuss with us what you would like, and we drop off the chair sample at your office so you and your staff can trial the chair properly before it is purchased. You can contact us at firstname.lastname@example.org.