Office, computer and remote workstations

Office work looks safe compared with lifting cases or using a jackhammer, but millions of people spend most of their working day sitting at a computer, and many develop neck, shoulder, back, wrist and eye problems. The risks come not from heavy force but from static postures held for hours, awkward reaches to keyboards and mice, screens at the wrong height or distance, poor lighting and too little movement. The rise of remote and hybrid work has moved many workstations to kitchen tables, couches and spare bedrooms, often with laptops and no adjustable furniture. This lesson explains how to set up office, computer, sit-stand and remote workstations that support comfortable, neutral postures and regular movement.

Risks of computer work

The main ergonomic risks of computer work include:

• Static postures: sitting or holding the head, shoulders and arms still for long periods, which reduces blood flow and causes muscle fatigue, especially in the neck and upper back.
• Awkward postures: reaching forward to a keyboard or mouse, bending the wrists up or sideways while typing, raising the shoulders when the desk is too high, and bending or turning the neck to view a screen or documents.
• Repetition: thousands of keystrokes and mouse clicks a day, often with little variation.
• Contact stress: resting wrists or forearms on hard desk edges.
• Visual demands: screens too close, too far, too bright or reflecting glare, small text, and long periods of focusing at one distance, leading to eye strain, dry eyes, headaches and compensating head postures.
• Prolonged sitting: long uninterrupted periods of sitting are associated with discomfort and with wider health risks; movement throughout the day is important.
• Organizational factors: heavy workloads, deadlines, electronic monitoring and few breaks, which increase muscle tension and reduce movement.

Start with the chair

A good office chair is adjustable to fit the user and supports a variety of postures. Adjust it in this order:

• Seat height: set it so that your feet rest flat on the floor with your thighs roughly horizontal and your knees at about the same height as your hips or slightly lower. If the desk is too high to allow this, raise the chair and use a footrest.
• Seat depth: you should be able to sit back against the backrest with a gap of about two to four finger widths between the front edge of the seat and the back of your knees. Use the seat slider or backrest adjustment.
• Backrest: adjust the height so the lumbar support fits the curve of your lower back, and set the tilt or recline so you can lean back slightly, which reduces load on the spine compared with sitting bolt upright.
• Armrests: set them low enough that your shoulders are relaxed, and close enough that they support your forearms lightly without pushing your elbows out. Armrests that are too high or too wide raise the shoulders; armrests that hit the desk keep you too far away. Remove or lower them if they get in the way.

Desk, keyboard and mouse

Once the chair is set, bring the work to you. The keyboard should be at about seated elbow height, so that your upper arms hang relaxed, your elbows are bent at about 90 degrees or slightly more, and your wrists are straight. Many standard desks are too high for this, which raises the shoulders and bends the wrists; an adjustable desk, a keyboard tray or raising the chair with a footrest can fix this.

• Place the keyboard directly in front of you, close enough that you do not reach forward. Use the keyboard flat or with a slight negative tilt; the small feet at the back of many keyboards bend the wrists upward and are often better left folded.
• Place the mouse right beside the keyboard at the same height. A compact keyboard without a numeric pad, or a keyboard with the number pad on the left, keeps the mouse closer. Alternate hands or use keyboard shortcuts to reduce mouse use.
• Keep wrists straight and floating while typing; palm supports are for resting during pauses, not for anchoring the wrists while typing.
• Keep frequently used items, such as the phone, documents and notepad, within easy reach, roughly within forearm reach while seated, and less frequently used items farther away.
• Use a headset for frequent phone calls instead of cradling the phone between the ear and shoulder.

Monitors

• Distance: place the monitor about an arm's length away, typically 50 to 100 cm (20 to 40 in), farther for larger screens. If you lean forward to read, enlarge the text rather than moving closer.
• Height: set the top of the screen at or slightly below eye level, so you look slightly down at the middle of the screen. People who wear bifocal or progressive lenses usually need the screen lower to avoid tipping the head back; computer glasses can help.
• Position: place the main monitor directly in front of you. With two monitors used equally, place them side by side with the join in front of you; if one is used mostly, put it in front and the other to the side.
• Tilt: tilt the screen back slightly so it faces your eyes.
• Text size and contrast: use text large enough to read comfortably without leaning forward, and dark text on a light background in a well-lit room.
• Documents: use a document holder placed beside the screen at the same height and distance, or between the keyboard and screen.

Lighting and eyes

Visual comfort affects posture: people lean toward screens they cannot read and twist away from glare. Typical recommendations for general office lighting are in the range of roughly 300 to 500 lux, with lower levels near screens than for paper-based tasks, and task lights for reading documents. Position monitors at right angles to windows to avoid glare from behind the screen or reflections on it, use blinds to control daylight, and avoid bright light sources in the field of view. Use the monitor brightness and contrast settings to match the room.

Focusing at a fixed distance for long periods tires the eyes and reduces blinking, leading to dry eyes. A common rule of thumb is the 20-20-20 rule: every 20 minutes, look at something about 20 feet (6 m) away for 20 seconds. Workers who use computers should have regular eye examinations and tell the eye care professional about their screen distance; some benefit from glasses prescribed for computer distance.

Sit-stand workstations and movement

Adjustable sit-stand desks let workers alternate between sitting and standing. Standing all day is not the goal: prolonged standing has its own risks, including leg and back discomfort and venous problems. The benefit comes from changing posture regularly. Practical guidance suggests changing position at least every 30 to 60 minutes, building up standing time gradually, and moving around when possible. When standing, set the desk so the keyboard is at standing elbow height and the monitor is raised accordingly; wear supportive footwear and consider an anti-fatigue mat.

Movement breaks and task variety are important whatever the furniture. Get up for phone calls, walk to talk to colleagues, use printers away from the desk, stretch, and vary tasks between screen work and other work. Many people find software reminders helpful. Employers can support movement by designing work and meetings to include it and by avoiding constant monitoring of keystrokes and idle time that discourages breaks.

Laptops, tablets and phones

Laptops are designed for portability, not for long periods of use. Because the screen is attached to the keyboard, either the screen is too low, bending the neck, or the keyboard is too high, raising the shoulders and bending the wrists. For regular use of more than about an hour or two a day, use a laptop stand or docking station to raise the screen to eye level, with a separate keyboard and mouse, or connect the laptop to an external monitor. Tablets and phones encourage looking down for long periods and gripping with the thumbs; use stands, keep sessions short, and switch to a full workstation for longer tasks.

Remote and hybrid work

Remote workers often use dining chairs, kitchen tables, couches and beds as workstations, with laptops and no separate keyboard or monitor. They may work longer hours with fewer natural breaks, such as walking to meetings. A good remote work program includes a home workstation self-assessment checklist with photographs reviewed by a trained person, guidance on setting up the space, provision or reimbursement of key equipment such as an adjustable chair, external monitor, keyboard, mouse and laptop stand, training, a way to report discomfort, and follow-up assessments when needed. Hybrid workers who share desks at the office need to know how to adjust each workstation quickly.

In Canada, employers' OHS duties generally extend to employees working from home, although the details vary. The Canada Labour Code Part II applies to federally regulated employees working remotely, and provincial regulators such as WorkSafeBC state that employers have responsibilities for the health and safety of workers at home. In some provinces, the OHS act excludes certain work in private residences, so check how your jurisdiction treats telework. Workers' compensation boards generally accept claims for injuries at home that arise out of and in the course of employment. CSA Z412-2024 now includes guidance for home offices.

Office workstation standards

CSA Z412-2024, the fourth edition of the Canadian office ergonomics standard, sets out a process for applying ergonomics to office work, including workstation design and adjustment, the visual and acoustic environment, work organization and home offices, and is aligned with the management approach of CSA Z1004. It is not law unless referenced, but it is widely used as the benchmark for good practice in Canadian offices.

Checking a workstation

A quick workstation check covers the following points. Can the user sit back in the chair with feet supported and thighs roughly horizontal? Are the shoulders relaxed and the elbows close to the body at about 90 degrees? Are the wrists straight while typing and using the mouse? Is the mouse beside the keyboard? Is the top of the monitor at or slightly below eye level and at about arm's length? Is there glare on the screen? Are frequently used items within easy reach? Does the user take regular breaks and change position? Does the user report any discomfort? Problems found in the check should be fixed and the user asked about their comfort after a week or two.