KANBrief 2/11
Some 18 million VDU workplaces are to be found in Germany. Over 45% of the workers at these workplace report back or neck pain, or similar complaints. Only when workplaces are designed ergonomically can it be ensured that workers will be able to work at them for many years without suffering complaints. One aspect of this is that the workplaces should be free of distracting reflections.
Anyone who has worked with a laptop with a high-gloss surface knows how annoying reflections can be. Generally, users avoid the reflections by adopting a different body posture, which may often prove ergonomically disadvantageous. Attempts to design the artificial lighting of workplaces or to exploit the natural light such that glossy work equipment can be used without causing disturbing reflections are soon found to be impossible.
For this reason, the EU Display Screen Directive (90/270/EEC: Minimum safety and health requirements for work with display screen equipment) requires screens and other work equipment to be free of disturbing reflections. Since 1969, standards governing lighting such as DIN 5035-1 have recommended matt surfaces for all work equipment. For over 30 years, the German statutory accident insurance institution for the administrative sector (VBG) has recommended matt work equipment, and the results have been universally positive.
This now looks to be changing, at least where monitor cases are concerned. Industry in the USA, in particular, is seeking to have requirements concerning the gloss level of monitor cases deleted from parts 303 and 307 of the ISO 9241-3xx series of standards, “Ergonomics of human-system interaction” (EN ISO 9241-303: Requirements for electronic visual displays; EN ISO 9241-307: Analysis and compliance test methods for electronic visual displays), during their revision. The manufacturers would like to free themselves from requirements for their devices which could prove an obstacle to marketing. The result would be that in future, monitors would appear on the market with glossy cases which would no longer satisfy the European Display Screen Directive: ergonomics would be sacrificed for the sake of greater freedom for trendy design approaches, even though the purpose of these product standards is to improve the ergonomic design of work equipment.
The effects of glossy surfaces
In CIE 146:2002 (CIE Collection on Glare, CIE 146:2002), the International Commission on Illumination states that the disturbances caused by glossy surfaces are a result of two different forms of glare.
• Disability glare (CIE 17.4 – 1987, International lighting vocabulary) is the glare which impairs vision by the diffusion of light in the eye. Owing to ocular opacity, older persons are more susceptible to disability glare than their younger counterparts.
• Discomfort glare refers to disturbing and distracting effects of sources of bright light in the peripheral field of vision which do not, however, necessarily impair vision. Discomfort glare may have a considerable impact upon the feeling of well-being, performance, and the ability to concentrate, and may contribute substantially to fatigue, since the gaze is subjected to continual, undesired distraction.
The US Occupational Safety & Health Administration (OSHA) classifies glare as a potential hazard: “Reflected light from polished surfaces, such as keyboards, may cause annoyance, discomfort, or loss in visual performance and visibility. To limit reflection from walls and work surfaces around the screen, paint them with a medium colored, non-reflective paint.”
KAN position paper focuses OSH interests
In order for users of standards to be able to attain the objectives of protection of the OSH Framework Directive (89/391/EEC: Measures to encourage improvements in the safety and health of workers at work) and the Display Screen Directive and to satisfy the provisions of the national legislation transposing them, the German OSH experts are lobbying for the existing provisions in the standards concerning the gloss levels of casings to be retained. KAN has drawn up a position paper which sets out a common OSH position. Since the OSH objectives can be carried through only with the support of OSH experts elsewhere in Europe and beyond, the latter are being asked to lend active support to the German position.
Cross-border co-operation between OSH representatives is all the more important given that revision of the European Display Screen Directive is planned. Here too it is crucial to ensure that as many ergonomic requirements concerning work equipment as possible are retained.
Dr. Peter Schäfer
peter.schaefer@vbg.de