2.1 · Health Hazards from ICT
Goal: identify physical and mental hazards of prolonged ICT use.
Physical hazards
| Hazard | Cause |
|---|---|
| Repetitive Strain Injury (RSI) | Repeated keyboard / mouse actions |
| Carpal Tunnel Syndrome | Nerve compression in wrist |
| Eye strain / Computer Vision Syndrome | Long screen time, blue light, low contrast |
| Neck / back / shoulder pain | Poor posture, badly designed chair |
| Dry eye | Reduced blinking when staring at screens |
| Headaches | Eye strain, dehydration, poor lighting |
| Hearing damage | Long-term high-volume headphone use |
| Obesity | Sedentary screen time |
| Sleep disturbance | Blue light + late-night use disrupts circadian rhythm |
Mental and social hazards
| Hazard | Cause |
|---|---|
| Anxiety | Constant notifications, social comparison |
| Depression | Excessive social media |
| Cyberbullying | Anonymity online |
| Addiction | Gaming, social media reward loops |
| FOMO (fear of missing out) | Real-time visibility into others' lives |
| Isolation | Substituting online for offline relationships |
Quick recommendations
- 20-20-20 rule — every 20 minutes look 20 feet (6 m) away for 20 seconds.
- Hourly micro-breaks — stand, stretch, blink.
- Volume limits on headphones (60% / 60 minutes is one guideline).
- Bedtime screen curfew — at least 30 minutes before sleep.
- Notifications off to reduce anxiety triggers.
Hong Kong context
- Many HK students report >6 hours of daily screen time.
- HK Department of Health publishes ergonomic guides for students.
- Government Smart City Blueprint mentions digital wellness.
Exam-style question
Q (5 marks): Describe three health hazards of prolonged ICT use and suggest one preventive measure for each.
Sample answer:
- RSI from continuous typing → take micro-breaks every 30 minutes; do wrist stretches; use ergonomic keyboard.
- Eye strain from screen exposure → 20-20-20 rule, adjust brightness, increase font size.
- Sleep disturbance from late-night screen use → enable night-mode (warm colour), avoid screens 30 minutes before bedtime.
Key takeaways
- Hazards are both physical (RSI, eye strain) and mental (anxiety, addiction).
- Simple habits prevent most issues.
➡️ Next: 2.2 Ergonomics