ISO 9241 Part 3: Visual display requirements


ISO 9241-3:1992 Ergonomic requirements for office work with visual display terminals (VDTs) -- Part 3: Visual display requirements.


International Standard. Wil be replaced by the ISO 9241-300 subseries.

Lifecycle Phase

Build the context of use.

Type of Guidance

Principles and general recommendations.

Application Area

  • Equipment
  • User testing


This part of ISO 9241 sets image quality requirements for the design and evaluation of monochrome and colour visual displays.  In the UK, the Health and Safety (Display Screen Equipment) Regulations 1992 require displays to be clear, legible and stable under normal working conditions. Displays that meet the requirements in this part of ISO 9241 are deemed by the Health and Safety Executive to satisfy this design requirement. The requirements in this part of ISO 9241 are stated as performance specifications and the standard provides test methods and conformance measurements. The specifications cover: design viewing distance; line-of-sight angle; angle of view; character height; stroke width; character width-to-height ratio; raster modulation and fill factor; character format; character size uniformity; between-character spacing; between-word spacing; between-line spacing; linearity; orthogonality; display luminance; luminance contrast; luminance balance; glare; image polarity; luminance uniformity; luminance coding; blink coding; temporal instability (flicker); spatial instability (jittter); and screen image colour. There are four annexes. The first provides analytical techniques for predicting screen flicker. The second describes an empirical method for assessing temporal and spatial instability (flicker and jitter) on screen. The third describes a comparative user performance test method: this annex has since been updated and re-issued as a separate document (ISO 9241-3:1992/Amd 1:2000). The final annex is a bibliography.


Manufacturers of visual displays (especially CRT displays) and people that need to evaluate the quality of visual displays. This is a technical standard that requires some knowledge of display design and human vision.

See Also

ISO 9241-3:1992/Amd 1:2000 Visual performance and comfort test.

ISO 13406-1:1999 Ergonomic requirements for work with visual displays based on flat panels -- Part 1: Introduction.

ISO 13406-2:2001 Ergonomic requirements for work with visual displays based on flat panels -- Part 2: Ergonomic requirements for flat panel displays.

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ISO 9241 for Beginners

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