Even in our small East African town more and more people are sitting in front of a computer day in day out, either because they must to get a day’s work done, or because they are hopelessly addicted to the stream of information available over the internet. These people do not realise they are in DANGER! Sitting in front of a computer all day is a hazardous activity. I am not talking about hackers, spyware or even the danger of electric shock. You are in danger simply by sitting in front of that monitor. Common problems include headaches, neck strain, back ache and wrist and forearm pain. Clearly using a computer is not as dangerous as your daily dalladalla journeys, but taking action to avoid the risks can improve the quality of your working life.
If you aren’t lucky enough to sit in front of a flat LCD monitor you will be using some kind of Cathode Ray Tube (CRT) monitor. These work by a beam (the cathode ray) scanning across the screen many times a second. The image on the screen changes with each scan. This causes the screen to flicker. The number of times per second that this happens is known as the Refresh Rate, and is measured in hertz (Hz). The lower the refresh rate, the more it is possible to notice the flickering of the screen. Many people find flickering lights bring on headaches and even nausea. A combination of fluorescent lighting (which also flickers) and CRT monitors can make things even worse. What is the solution besides popping down to the local computer store and buying a fancy LCD monitor? Increase the refresh rate of course!
To change the refresh rate click on the windows desktop with the right hand mouse button, and select Properties. In the window that pops up select the Settings tab, and then click the Advanced button. Another window will pop up. Click the Monitor tab on this window and you will see information about your monitor. There is a drop down list of Refresh Rates that your computer can use. By default, Windows uses 60 Hertz. Most monitors support rates of 75 or higher. If you change the setting and the screen goes blank, hit the Esc key to return to the previous setting. Increasing the refresh rate can make a noticeable difference to flickering, and can reduce headaches in some computer users.
Assume the position
Many computer users sit with their keyboards parallel with the edge of their desk, and the monitor sitting at an angle to the left or right. When typing the user has to twist their head to one side in order to see the screen. This can cause neck strain, especially when using the computer for long periods of time. Ideally, the monitor should be positioned directly in front of the keyboard.
Staring into space
Eye strain can also lead to headaches. You should avoid looking at the screen continuously for long periods of time. If possible you should look away from the screen for a minute for every fifteen minutes you are working. It has been suggested that this can reduce the risks of eyesight deterioration later in life. Regular breaks for your hands are also useful in preventing Repetitive Strain Injuries (RSI).
Basking in radiation
A lot of people use special filters which hang over the front of the monitor screen. These screens are supposed to filter out radiation from monitors. From what I have read there is no real risk from this radiation. It is a lot less than given out by mobile phones. So do you need a filter? If you use one, try using your computer both with and without. I have found that a lot of filters increase reflections, making it harder to read what is on the screen. This is another cause of headaches. Your filter may reduce reflections, in which case use it.
Using computers of course is very safe. You aren’t about to fall out of an open door at 80 kph, but you can make it safer and more enjoyable.
- www.yale.edu/oehs/vdtguide.htm – lots of tips on how to set up your computer so you are working safely
- www.workrave.com – free software that reminds you to take regular breaks from your computer
- del.icio.us/dunxd – my regularly updated list of links
And the winner is…
We have a winner for the competition to win a Microsoft 32Mb data key. Congratulations to Gervase Mlola, whose vision of Arusha in ten years time includes security guards in control towers monitoring the activity in the streets using cameras and mirrors. Big brother is watching you! Special mention to Georgette Byela, whose vision included robots directing traffic around Arusha’s streets. Thanks to everyone who entered. Look out for another competition very soon.
Originally published in Arusha Times 312