Eye-related complaints are one of the main problems cited by computer users. The most common of these are eye strain, eye fatigue, eye irritation and blurred vision. Computer users also complain of tired, burning, itching and watering eyes, headaches, flickering sensations and double vision.
People who spend a lot of time at computers can take preventive steps to minimise their effects on the eyes. An adjustable chair will allow the user to set the chair for most comfortable height and back support.
The top of the VDU screen should be approximately 10 degrees and the centre of the screen 20 degrees below the user's straight-ahead seeing position. The appropriate distance from the viewer's eyes to the screen should be about 35 to 40 centimeters.
Reference material should be placed as close as possible to the VDU screen. This avoids large head and eye movements, which are tiring. Where possible, reference material and the VDU should be placed the same distance away from the eyes, reducing the need for frequent changes of focus, which can contribute to visual discomfort.
Lighting is important but needs vary depending on individuals, the nature of the task and the layout of the office. It is usually desirable for the VDU screen brightness to be three to four times greater than ambient office lighting and there should be a high degree of contrast between the characters on the screen and the background.
Try to minimize reflected glare on VDU screens by positioning them so that windows and other sources of bright light are not behind the user. Do not sit facing an unshaved window or other source of bright light. Small hoods can be attached above the screen to shield it from excessive overhead light and special monitor shields are available, which can be fastened to the front of the screen, to eliminate glare and reflection.
Vision and Driving
Good vision is essential for safe driving - if you cannot see properly, you cannot drive safely.
Statistics show that one driver in 14 has a vision defect that may affect their driving. If you think your eyesight may not be adequate, visit your optometrist and get it checked. In Australia eye exams are covered by Medicare.
- Distance Vision
Even the simplest reactions can take 0.4seconds. If your distance vision is poor, you may not see hazards until it is too late to react safely.
The faster you travel, the less time you have to see things and react to them. Poor distance vision and excessive speed can have disastrous results.
Distance vision can also be affected by the state of your windscreen and spectacles. These should be kept clean and free of dust and scratches.
- Peripheral Vision
The ability to see to both sides without moving your eyes or head is important. You need to be able to see cross traffic, pedestrians and animals at the roadside, without looking away from the road ahead. Make the best use of your side and rear-view mirrors.
- Depth perception
You need to be able to judge distances will and pass other vehicles and change lanes, especially in busy traffic.
When you are driving, you often need to look from the road to the dashboard and back again. This ability to change focus from far to near is called accommodation. Over the age of 45 years, most people have increasing difficulty with near vision and may need spectacles to see the dashboard clearly.
- Night Vision
You need to be able to see in low and variable light conditions, and recover quickly from the glare of oncoming headlights. Glare recovery is best in drivers under the age of 30 years, and night vision can deteriorate after the age of 40.
Eyes are much slower to adapt to night-time light levels after they have been exposed to bright light. Being outside in the sun for only a few hours can slow your eyes' adaptation speed, so you might not have your normal night vision for several hours after dark. You can avoid this by wearing sunglasses during the day.
- Color vision
Drivers must instantly recognize traffic lights, indicator signs, hazard warning lights and stop lights, and people with color vision defects may react slower to them. Medium or dark blue sunglasses can seriously interfere with some people's ability to distinguish traffic signal colors.
Keeping your eyes safe
It is estimated that 95 per cent of eye injuries treated in the casualty departments of Australian hospitals are the result of carelessness and lack of attention to basic safety precautions.
The vast majority of eye injuries are preventable and can be avoided by taking a common sense approach to potentially hazardous activities.
Nearly half of all eye injuries occur around the home or during leisure activities. If you are aware of potential hazards and follow a few safety precautions, you may save your own or someone else's sight.
- At home
- Take special care when using cleaning products or harsh chemicals. Read all the instructions before use and wash hands well after use.
- Wear safety goggles when using powerful chemicals to protect your eyes from splashes and fumes.
- Make sure that you point spray nozzles away from you
- In the workshop
- Always wear goggles or safety glasses.
- Read the instructions for all tools and chemicals before using and follow directions for proper usage, observing any special precautions.
- Keep all tools and power equipment in good repair.
- Extinguish cigarettes or matches before working around flammable materials or opening the bonnet of a car.
- Around the yard
- Pick up rocks and twigs before moving the lawn.
- Keep others away from the area where you are mowing
- Wear safety glasses or goggles, especially when chopping wood or trimming bushes and trees.
- When securing objects with octopus straps, pull the strap to the side of your body rather than towards your face.
- When playing sports
- Observe safety rules when you play
- Wear safety glasses, especially for racquet sports.
- Wear protective helmets or face protectors, when appropriate.
Ask your optometrist minimizing risks for different activities.