A Guide to Ergonomics in the Office

What is ergonomic office furniture?

Ergonomics is the science of designing and arranging specific items such as furniture to ensure that human interaction with the product is performed in the most comfortable, efficient and safe way, most importantly making sure to reduce the risk of injury caused by stress or strain. Ergonomically correct and comfortable seating should ensure stable body support for a variety of postures and allow for a certain amount of movement and changing posture.

Why is it important to consider ergonomics in the office?

Both statistics and studies highlight that ergonomic seating is something that all employers should consider in their workplace. Working in an office typically involves spending the majority of your day sitting in an office chair and this position can add stress to the structures of the spine – which, over time, can lead to the development of back problems. Experts agree that your chair is perhaps the single most important component of a healthy working environment. Therefore, it is important to provide your employees with an office environment that is ergonomically designed in order to not only avoid injury and lessen the amount of lost days due to such injury, but also to increase productivity.

Choosing the Right Ergonomic Office Chair

Choosing your office chair:

A good ergonomic office chair should:

  • Promote good posture
  • Provide proper support for the body in a range of postures
  • Be suitable for the intended purpose, enabling you to work comfortably, freely and efficiently
  • Reduce the amount of strain on a number of the body’s pressure points
  • Be suited to the user or fully adjustable for each user
  • Be suitable for the workstation including the height of the desk and arrangement of equipment

No one type of office chair is necessarily the best or most ergonomic as it is partially dependant on your individual needs and working style, however, there are some things that are very important to look for when choosing a good ergonomic chair.

Seat height

Perhaps the most important feature of an ergonomic office chair is the ability to adjust the height of the seat. For the majority of users, a seat height that ranges between 16 and 21 inches from the floor will be suitable. This should ensure that when sat down, your feet rest flat on the floor with the bend in your leg forming a 90 degree angle. It is worth investing in a foot stool if this position cannot be achieved. If your desk is not adjustable, you should adjust your seat to make sure your elbows are in line with or just above the table top when resting your arms on the armrests.

If the positioning of the chair is too high, there will be too much pressure on the sensitive area of the leg behind the knee and can restrict blood circulation and cause numbness. If the seat is too low, the thighs will not be positioned horizontally causing the body weight to shift back and put pressure on the sitting bones.

Seat width and depth

The width of the chair should be enough to provide a comfortable seat, with around 17 to 20 inches being the standard. The seat needs to have enough depth to support the user comfortably, whilst allowing them to sit with their back against the backrest. A good guideline is to give 2 to 4 inches between the back of your knees and the front edge of the seat.

If the seat has too much depth, you are likely to prop yourself forward and consequently lose the all-important benefits of the backrest and cause strain on your back and legs. If you are not able to adjust the seat depth, you should make sure the chair still allows for you to sit right at the back of the seat in order to correctly use the backrest and support your lumbar.

Backrest/Lumbar support

The lower back, or more specifically, the lumbar spine has a natural curvature and so a chair that can be adjusted to best fit this curvature will provide the greatest comfort, especially when sitting for longer periods of time. To properly support the lower and middle back, it is essential that the chair is equipped with an appropriately sized backrest. However, make sure that the size and shape of the backrest doesn’t cause limited arm or shoulder movements; use 12 to 19 inches wide as a rough guide.

If the lower back is not supported properly, the user is likely to sit in a slouched position, causing the natural curve to flatten and putting strain on the structures in the lower spine. A good ergonomic chair should have lumbar adjustment features, allowing each user to alter the height and depth of the backrest to fit their size and shape accordingly.

Backrest Tilt

The backrest should be adjustable and able to tilt forward and backward with a locking mechanism to secure it once the user has adjusted the angle appropriately. For optimal comfort, the angle between your thighs and your back should be around 95 to 105 degrees. This should ensure that when sitting, your abdomen and chest are open and not compressed. Opening up this angle facilitates better breathing, sending more oxygen to your muscles and increasing blood flow to your brain. During rest breaks, a reclining chair will also help you to relax your back.

Armrests

The arms represent just over 10% of our total body weight, which can result in significant exertion in the muscles of the upper back, shoulders and neck. Therefore, a good ergonomic chair will always have armrests, and these should be adjustable (width and height) to accommodate the size range of users. You should be able to sit at your desk with your arms resting comfortably in line with your desk and your shoulders relaxed. To reduce the risk of muscle fatigue and unnecessary strain on your back, it is advised that your forearms are not resting on the armrests when typing. Adequate padding is also recommended for maximum comfort.

Seat Material

Choosing the right material is very much dependent on the amount of time spent in the seat and the operating circumstances. However, to maximise comfort, especially if the chair is to be used for a longer amount of time, opt for a permeable material such as a cloth fabric. This ensures that the seat can breathe and avoids a build-up of heat. Although leather may look sleek and feel comfortable, it is best avoided if you will be sitting for 8 hours a day as it does not dispense heat particularly well.

For most, a softer surface is preferable to a harder one, and regardless of the material used, the seat should have enough padding to be comfortable to sit in for extended periods of time. For the backrest, mesh is a good choice as it is both breathable and comfortable.

Swivel/Mobility

Office chairs that will be used at a desk should swivel/rotate so that the user can easily reach other parts of their workspace without straining or overreaching. Casters (wheels) are an essential feature necessary for the user to move freely. Before purchasing, make sure to check that the casters are appropriate for the type of flooring in the office. For carpeted floor opt for hard casters and for harder surfaces like wood choose rubber coated casters to avoid marking or scratching the floor.

To sum up...

Choosing the right ergonomic office chair is very important to the user’s overall health and work productivity, particularly in a working environment when the user is likely to be sat in the chair for long periods of time. It is important to note that no one chair is suitable for all users so you need to assess the shape and size of each user as well as their work space and the necessary requirements.

Most people will be surprised by the amount of tension and stress on the body that can be reduced just by choosing the right chair. However, once you’ve chosen your office chairs, make sure you and your staff know how to use the features properly in order to enjoy the many benefits of your ergonomic chair.

How to ergonomically organise your workspace

Keyboard

Your keyboard should ideally be positioned with a negative tilt and with the alphanumeric part of the keyboard in the centre of your desk - or better still, purchase a keyboard without a number pad. When sat in your chair, your forearms should sit at a 90 degree angle to your keyboard if possible.

Mouse

Your mouse should be placed right next to your keyboard or at least within easy reach. Keep your wrist in a natural and comfortable position when using your mouse or if you feel the need to further minimise stress on your wrists, consider using a wrist rest.

Monitor

Your monitor should be approximately an arms width away from you – any further is likely to cause eye strain or what ergonomists call “turtling” (craning your neck). In terms of height, aim for your eye level to be near to the top of your monitor. Tilt the screen down slightly if there is the need to eliminate glare/reflection.

Key objects

Keep any frequently used objects (telephone, writing equipment, books etc) close to your body to prevent excessive stretching.

Desk

As people become more aware of the negative effects on health due to prolonged sitting, they are turning to a popular solution: standing desks. Although there are some known benefits including improved posture, much like sitting all day, standing for long periods of time is not particularly healthy either. It is best to find a comfortable balance between sitting, standing and moving around. Therefore, you may want to consider a height adjustable sit-stand desk. These allow you to regularly and easily switch between sitting and standing positions and thus a range of different postures throughout the day. As well as feeling healthier, experts believe it to improve posture, focus and productivity and also to reduce or eliminate back pain.

Take regular breaks!

One final tip is to take hourly breaks away from your workstation. Get up and walk around even if it is just for a couple of minutes. Giving your body a quick stretch and briefly taking your eyes away from the screen can reduce eye strain, ease tension and help you to stay alert without reducing productivity. Getting into the habit of taking regular breaks could ultimately help to combat the health issues that arise from prolonged sitting.