Very few of us these days escape the need to use a computer screen or visual display unit attached to a machine. Those using a PC or VDU on a regular basis, not necessarily full time but doing a regular weekly or daily task are covered by the Health and Safety Act on VDU display workers. Click here for information on VDU legislation. VDUs will not damage your eyes but if used incorrectly can cause tiredness in the eyes and muscle and skeletal problems in the body if the work station is positioned incorrectly.
These are caused by focusing problems for some, but in the main much is created by dry eyes which is exacerbated by those suffering from a little recognized Dry Eye Condition. When the mind is concentrating on a visual task, the body’s blink rate slows to as little of 40% of the norm, and this causes the tear film covering the eye to dehydrate and break up. As it’s necessary for good vision images then become slightly blurred and more difficult to focus. It is laid down in the legislation that VDU workers must take adequate breaks, but you can help your eyes by following the 20:20:20 blink rule. This means that every 20 minutes you should look away from your screen to a distant object for 20 seconds and make an effort to blink 20 times. Probably not a good idea to fix focus on your boss or the good looking person you admire! If eyes still feel tired, itchy or have a burning or dry feeling you can try eye drops to alleviate the problem. Click here for Dry eye information.
The work station should where possible be set near or facing a window to allow for a change of focus, setting it in a position with a window behind will cause far too many reflections and will require a good screening system. Facing a blank wall immediately behind the screen will necessitate turning around to re-focus on long distance.
The work station must legally be fit for work with a reasonable surface to put papers on or a paper carrier for copy typing, as well as a multiple adjustable chair, in height, back slope and squab slope. Your arms should be at least parallel to the keyboard and have wrist support where required. The screen should be at eye level for PCs but this is not possible for a laptop. In order to accommodate working documents, screens are often placed higher but this means the eyes are being used in an uncharacteristic fashion looking upwards, which can produce eyestrain and a lack of blinking.
Those who find focusing a strain should ask for a VDU screening test or a full sight test to be provided by their employer. Spectacles that are specifically required for the VDU work should be paid for by the company and some companies will make a contribution even if specs are needed for other activities including the VDU usage.
We recommend anti reflection coated aspheric lenses as these will give the best definition of image with an added coating of UV blocking coating offering the eye protection against harmful UV rays.
For those of you presbyopes where you need two focusing lens powers, distance being different from close work, you will find reading copy and seeing the key board as well as looking at the screen a bit of a nightmare with bifocals and your head will need to be tilted to accommodate this problem. Rather than a crick in the neck there are special lenses in varifocal form called degressives which will solve the problem.
We’ve all experienced trying to view our monitor or somebody else’s screen with our varifocals, or bifocals and whilst these a great for reading books which you can place in the right position they are literally a “pain in the neck” for static viewing of screens or machinery. Often spectacle wearers are unaware of the reason of their bad posture at work but take a look at your colleague and you will soon spot craning neck postures and a tendency to always want the seat at its highest position.
The answer is in specialist varifocal lenses which are designed to give comfortable viewing above the normal level of reading set at your VDU screen distance. In our view too little information is provided to spectacle wearers about these lenses and admittedly they are an extra purchase but you can gain great comfort and they make work a lot more bearable.