Basic 9 · Computing · Health and Safety in the Use of ICT Tools
Health Issues at Workstations
In this topic you will evaluate the potential health issues associated with computer workstations, and explore the importance of good posture, ergonomics and proper lighting.
By the end of these notes you should be able to:
- Identify health problems linked to computer use
- Explain good posture and ergonomics
- Evaluate lighting at a workstation
What you already know
- Safe use of ICT tools
Copy everything that has a blue line on its left into your notebook. The other parts are for reading.
Lesson 1
- Strand
- Introduction To Computing
- Sub-strand
- Health and Safety in the Use of ICT Tools
- Indicator
- B9.1.3.1.1 – Evaluate health issues at workstations
Introduction
A computer does not seem dangerous. Yet hours of sitting and staring at a screen can harm your eyes, back and wrists.
1. Common Health Issues
| Problem | Cause | Symptoms |
|---|---|---|
| eye strain | long screen time, glare | sore eyes, headaches |
| back and neck pain | poor posture | stiffness, pain |
| repetitive strain injury | repeated movements | pain in wrists and fingers |
| carpal tunnel syndrome | pressure on a wrist nerve | numbness, tingling |
| poor circulation | sitting for too long | swollen legs |
| weight gain | lack of exercise | lower fitness |
| sleep problems | screens at night | difficulty sleeping |
| stress | too much information | tiredness and anxiety |
2. Eye Strain
When you look at a screen, you blink less. This can make your eyes dry and sore. Bright screens, glare and small text make it worse. Doctors advise the 20-20-20 rule: every 20 minutes, look at something 20 feet (about 6 metres) away for at least 20 seconds. Keep your screen at about arm's length, and increase the text size if needed. If you often have headaches or blurred sight, you should get your eyes tested.
3. Repetitive Strain Injury
Repetitive strain injury: Damage to muscles and nerves caused by repeated movements.
Typing and using a mouse for long periods can cause RSI. Teenagers can also get it from long periods of texting and gaming. Keep your wrists straight and relaxed. Do not press too hard on the keys. Take breaks, and stretch your hands and fingers. People who do a lot of typing, such as secretaries, should take care to set up their workstation correctly.
4. Phones and Tablets
Looking down at a phone bends your neck, which puts extra strain on your spine. This is sometimes known as "text neck". Hold the phone higher and use both hands. Listening at high volume through earphones can harm your hearing, so keep the volume at a moderate level. Avoid using phones in the dark, and put them away at least an hour before you go to sleep.
5. Mental Health
Long hours online can affect your mood and sleep. Social media may lead you to compare yourself with others, and cyberbullying can cause real pain. Online games can become addictive. Balance your screen time with exercise, friends, family and study. Set time limits, and take days off from your phone. If you feel unhappy or unable to stop, speak to a parent, teacher or counsellor. Your health is worth more than any device.
New words
- eye strain
- Tiredness of the eyes.
- repetitive strain injury
- Harm from repeated movements.
- carpal tunnel syndrome
- Pressure on a nerve in the wrist.
- glare
- Bright light reflecting from a screen.
Summary
- Long computer use can harm the eyes, back and wrists.
- The 20-20-20 rule reduces eye strain.
- Balance screen time to protect physical and mental health.
Class activity: Health Audit
- Keep a record of your screen time for one day.
- List any symptoms you noticed.
- Suggest two changes.
You need: Computer chair, Keyboard, Printed workstation-posture chart
Exercises
Answer in your exercise book first, then check your answers.
1. Which is caused by long screen use?
- A. eye strain
- B. malaria
- C. cholera
- D. ringworm
Show answer
Answer: eye strainEyes.2. RSI is caused by…
- A. repeated movements
- B. dirty water
- C. loud music only
- D. too much sleep
Show answer
Answer: repeated movementsStrain.3. You blink less when looking at a screen.
- A. True
- B. False
Show answer
Answer: TrueDry eyes.4. Bright light reflecting from a screen is ______.
Show answer
Answer: glareVision.5. Explain the 20-20-20 rule.
Show answer
Answer: Every 20 minutes, look 20 feet away for 20 seconds.Eye care.6. State two ways that heavy phone use can affect a teenager.
Show answer
Answer: It causes neck strain and poor sleep, and can affect mood.Effects.
Lesson 2
- Strand
- Introduction To Computing
- Sub-strand
- Health and Safety in the Use of ICT Tools
- Indicator
- B9.1.3.1.1 – Evaluate health issues at workstations
Introduction
Your computer should fit you, not the other way round. This is the idea behind ergonomics.
1. Ergonomics
Ergonomics: Designing work and equipment to fit the human body.
Ergonomics aims to make work comfortable, safe and efficient. Good ergonomics reduces injury and increases productivity. It does not always cost money. Sometimes you can raise a laptop on books, adjust a chair or simply move a screen away from a window.
2. Setting Up a Workstation
| Item | Correct position |
|---|---|
| top of screen | at or just below eye level |
| distance from screen | about an arm's length |
| chair | supports the lower back |
| feet | flat on the floor or a footrest |
| knees | at about a right angle |
| elbows | close to the body, at a right angle |
| wrists | straight, not bent |
| keyboard and mouse | close, at the same level |
3. Good Posture
- Sit back fully in your chair.
- Keep your back straight and your shoulders relaxed.
- Keep your head level.
- Keep your forearms parallel to the floor.
- Stand up and move every hour.
Short, regular breaks are better than long, occasional ones. Stretch your neck, shoulders and wrists. A school with old furniture may not have adjustable chairs, but learners can still sit properly, and teachers can adjust where screens are placed.
4. Proper Lighting
Good lighting reduces eye strain. Light should be bright enough to read paper easily but not so bright that it washes out the screen. Natural light is pleasant, but a window behind the screen makes you squint, and a window behind you causes reflections. Position the screen at a right angle to windows, and use blinds or curtains to control sunlight. Do not work in a dark room with a bright screen, because the contrast tires the eyes.
| Problem | Solution |
|---|---|
| glare on screen | move the screen, use blinds |
| dim room | add a lamp |
| very bright screen | lower the brightness |
| flickering lights | replace the tube |
| strong sunlight | use curtains |
5. Comfort and Temperature
Stuffy, hot computer rooms are unpleasant and cause tiredness, and they can damage equipment. Fans, air conditioners and good ventilation keep rooms comfortable. Keep noise low to reduce stress. Drink water, and don't eat at your computer. A comfortable environment helps you to think clearly and to produce better work. Employers in Ghana have a duty under the Labour Act to provide a healthy workplace.
New words
- ergonomics
- Designing work to fit the human body.
- posture
- How a person holds their body.
- workstation
- A desk area with a computer.
- ventilation
- The flow of fresh air.
Summary
- Ergonomics makes work safer and more comfortable.
- Set your screen, chair and keyboard at correct positions.
- Good lighting prevents glare and eye strain.
Class activity: Workstation Check
- Check a workstation against the table.
- Measure the height and distance of the screen.
- Suggest three improvements.
You need: Computer monitor, Desk lamp, Printed glare-safe workstation chart
Exercises
Answer in your exercise book first, then check your answers.
1. Ergonomics fits work to the…
- A. human body
- B. printer
- C. router
- D. weather
Show answer
Answer: human bodyDefinition.2. The top of a screen should be…
- A. at or just below eye level
- B. far above the head
- C. on the floor
- D. behind you
Show answer
Answer: at or just below eye levelPosition.3. Breaks reduce strain.
- A. True
- B. False
Show answer
Answer: TrueHealth.4. A desk area with a computer is a ______.
Show answer
Answer: workstationSetup.5. Describe how to sit at a computer.
Show answer
Answer: Keep your back straight, your feet flat and your elbows at a right angle.Posture.6. How should a screen be placed relative to a window?
Show answer
Answer: At a right angle to the window, to reduce glare.Lighting.
Homework
- Improve your study or computer space and describe the changes.