Information on VDU workstations
VDU (visual display unit or screen) work is hard labour for the eyes.
Here, the eyes perform very monotonously. The increasing linking between duties and EDP often requires it to spend 100 % of the daily working hours in front of the VDU.
The eye wanders freely while seeing, and the requirements are balanced. VDU work overexerts the eyes due to significantly increased and frequently changing adaptations to different levels of light and distances. The eye has to effect different performances, depending on what prevails, data input activities or dialogue activities. 12,000 to 33,000 movements of the head and the eyes between VDU, keyboard and text material and 4,000 to 17,000 pupillary reflexes per day. At the same time, VDU work sub-challenges by means of the rigid view of equally close distances, at the same angle, and on the same objects.
The consequences exact their toll:
30 – 40 % of the employees at workstations complain about frequent and permanent discomfort of the eyes, nearly 2/3 at data input workstations. Tired, burning, and watery eyes do not only impair the overall performance but also the failure rate when reading something on the screen. Further consequences may include hardenings of the neck and headaches.
Recommendations for VDU Workstations
Whenever possible, a flat screen should be used. Concerning a tube monitor, a preferably high image refresh rate can improve the image quality. The screen should be positioned crossways to the window area and ceiling lighting. The screen should not stand too high as well.
The lighting must neither result in reflexions nor in specular reflections on the screen surface.
The office chair should support the whole body, it should be adjustable in height, and it should have a swivel function. The correct distance between screen and eyes is the most important precondition for fatigue-proof vision. The proper distance is 50 to 80 centimetres.
Periodically, you should allow yourself as well as your eyes a break from the screen work. Several short breaks are more effective than one extended break.
An ophthalmologist should examine anyone who works with a screen regularly. Frequently, precisely customised glasses or contact lenses can make work considerably easier.
The less the eye can adjust itself to different distances the more decisive is it that the correction values of the eyeglass lenses are precisely tailored to the viewing distances necessary for screen work.
The ophthalmologist prescribes verifocal lenses that are specifically designed for screen work. These lenses are tailored to fit the special distances at the VDU workstation, thus ensuring the highest sharpness of vision on the monitor and at the keyboard.
Anti-reflexion coating is recommendable in any case because it reduces potential reflexes on the eyeglass lens.
Applicable law for VDU work
The increasing importance of the workplace has brought the legislator to the scene at the beginning of the year 1997:
The hitherto applicable EU Directive 90/270/EEC – display screen equipment – was transferred into national binding law on 01.01.1997.
Subsequently the main extracts of the VDU Directive laid down in law that are important with regard to vision.
Federal Law Gazette year 1996 part 1 no. 63, excerpt, Display Screen Equipment Directive (EEC) from 20.12.1996:
§ 2 par. 3:
Employees to the purposes of this directive are employees usually using a visual display unit (VDU) during a significant part of their normal work.
§ 6 par. 1:
The employer has to offer the employees an adequate examination of the eyes and of the vision by an expert before commencing work at VDU workplaces, subsequently at regular intervals as well as in case of occurrence of visual discomforts that can be attributed to the work at VDU workplaces …
§ 6 par. 2:
The employees are to be provided with special visual aids for their work at VDU workplaces if the results of an investigation according to par. 1 ensue that special visual aids are necessary and that normal visual aids are unsuitable.