Module 1 – Computer Essentials

Lesson 5 – Health, Safety and the Environment

Computers are used for long periods in homes, schools and workplaces. To work safely and comfortably, users must
understand ergonomics, good workstation setup, posture, screen health, environmental considerations, accessibility
and safe digital habits. This lesson covers key aspects of responsible computer use.

Learning outcomes

By the end of this lesson, you should be able to:

• Set up a workstation using basic ergonomic guidelines.
• Describe good seating posture and common health risks such as RSI and eye strain.
• Apply safe working practices around equipment, cables and power.
• Identify common accessibility tools that support different user needs.
• Explain how to reduce environmental impact when using computers.
• Describe simple cyber safety and responsible use behaviours.

Quick warm-up

Think about where you usually use a computer. Ask yourself:

• Is your screen at eye level?
• Are your feet flat on the floor?
• Do you take regular breaks?

1. Ergonomics and workstation setup

Ergonomics is the science of designing a workplace to suit the user. Good ergonomics prevents
strain, discomfort and long-term injury.

Correct workstation layout

• Chair – adjustable height, supportive backrest, feet flat on the floor or on a footrest.
• Desk – stable surface with enough space for keyboard, mouse and monitor.
• Monitor – top of the screen at eye level, at arm’s length distance.
• Keyboard – positioned so arms are at 90 degrees; wrists kept straight.
• Mouse – kept close to the keyboard to avoid reaching.
• Lighting – should minimise screen glare.

Seating posture

• Sit upright with back supported.
• Keep shoulders relaxed.
• Place feet flat on the floor.
• Avoid slouching or leaning forward.
• Keep wrists straight when typing.

2. Avoiding common health problems

Repetitive Strain Injury (RSI)

RSI is caused by repeated movements such as typing or mouse use.

• Take short breaks every 30–45 minutes.
• Use an ergonomic keyboard or wrist support if needed.
• Relax fingers and hands regularly.

Eye strain

Long screen use can cause dry eyes, headaches and blurred vision.

• Follow the 20-20-20 rule (every 20 minutes look at something 20 feet away for 20 seconds).
• Position the screen at the correct distance.
• Reduce glare with good lighting.
• Adjust brightness and contrast.

Back and neck pain

• Adjust chair height and backrest.
• Keep monitor at eye level.
• Avoid twisting your body while working.

3. Safe computer working practices

• Take regular breaks.
• Keep liquids away from computers.
• Tidy cables to prevent tripping hazards.
• Do not overload power sockets.
• Use surge protectors.
• Lock your screen when leaving your desk.

4. Accessibility and inclusive computing

Accessibility tools help people with disabilities or additional needs use computers effectively.

• Screen readers – read text aloud.
• High contrast mode – increases visibility.
• Magnifier – zooms in on screen areas.
• On-screen keyboard – enables typing without physical keys.
• Speech recognition – control the computer with voice.
• Closed captions – support hearing-impaired users when watching videos.

5. Environmental considerations

Energy saving

• Use sleep mode when not using your computer.
• Shut down your device at the end of the day.
• Lower screen brightness.
• Use energy-efficient devices and power settings.

Reducing printing and waste

• Think before printing.
• Print double-sided where possible.
• Use recycled paper.
• Store files digitally instead of printing.

Recycling electronic waste (e-waste)

• Do not throw electronics in general waste.
• Use certified recycling centres.
• Follow local laws and guidance.
• Wipe or securely remove data before recycling devices.

6. Workspace cleanliness and computer care

• Clean keyboard, mouse and screen regularly with suitable cleaning materials.
• Keep air vents free of dust to avoid overheating.
• Use a surge protector to protect devices from power surges.
• Store devices safely and avoid dropping or knocking them.
• Keep food and drink away from equipment.

7. Cyber safety and responsible use

• Do not share passwords.
• Use strong, unique passwords.
• Avoid unsafe websites and downloads.
• Be cautious with public Wi-Fi.
• Log out of accounts on shared devices.
• Follow organisational online behaviour rules and policies.

8. Practical Activity

Try these tasks to apply what you have learned:

• Adjust your workstation following ergonomic guidelines.
• Enable one accessibility feature (for example, Magnifier or High Contrast mode).
• Perform the 20-20-20 eye-break method during a work session.
• Set your computer to sleep after a suitable period of inactivity.
• Organise your workspace and secure or tidy cables.
• Create a simple recycling plan for old devices and printer cartridges.