Acceptable visual distances at the computer monitor

The first office workplaces with VDTs installed during the 1970s have been designed following the ideas after which the workstations of military flight controllers had been designed a further decade ago. The users of these workstations have been healthy young man with controlled eyesight. And for safety reasons, they were not allowed to work longer periods of time. Thus, they did not feel a problem working at visual distances of about 330 mm – a legacy of the ophthalmologists of the 1920s who had fixed this reading distance. That this distance was not adequate, even for cutting onions in a kitchen, did not matter.

People working in offices perform different tasks than military flight controllers, their average age is much higher, and more than half of them is „visually handicapped“ – they need glasses. With a standard visual distance of 330 mm, at least half of the office workers beyond the age of 40 would need reading glasses even if they can live without in their usual environment. In addition, research from the late 1960s had revealed that the usual correction of the eyes of people wearing glasses was not adequate for at least 30% of the population. Would such people be able to work „9 to 5“ with a computer monitor?

This photo, still being cloned in various publications of all kind, has convinced even the militant ophthalmologists. It was possible to standardize the visual distance for future workplaces to 500 mm. Many physiologists would suggest a much longer distance. The newest ISO-standard on workplace design has successfully changed it to 600 mm. People shall be able to change their distance to the monitor by ± 150 mm. Thus, a comfortable range of 450 mm to 750 mm has been standardized. A dream for many millions of users who suffer from near visual work – even in one of the biggest countries of the world: Desks in the USA mostly do not support such distances. It is interesting to watch how they cope with this health hazard.

By the way, the photo made it to one of the most remarkable graphics on the development of the human being: