Visual display requirements: on standards and their users

A new ISO standard for visual displays: "Ergonomic requirements and measurement techniques for electronic visual displays" is soon to be released as a Draft International Standard. The core of the new standard is the part with generic ergonomic requirements for visual displays. Three parts of the standard describe three types of measurements: electro-optical ones, to be used in general; user performance test methods, for innovative displays for which no electro-optical methods exist; and field assessment methods, to be used outside of the laboratory, under the conditions of use at the workplace. The last part of the standard describes five compliance routes and procedures for five different display technologies and contexts of use. A number of choices and problems that standard writers have to face are mentioned. Should a visual display standard be written primarily for young users, with mostly a high visual acuity and in possession of their full accommodative power, wanting to use tiny hand-held displays featuring very small characters ? Or should the standard be focused on the elderly, with their reduction in visual faculties, barring the use of small characters that may irritate or disable such older users ? The question how to put human factors principles in standards sometimes seems a battle between idealists and realists. It therefore is important to strike a balance between different attitudes, backgrounds and interests in a standards writing committee - as indeed happens in ISO/TC 159/SC 4/WG 2, "Visual Display Requirements". The author is convener of this Working Group.