Maps for the colour-blind are a real eye opener

08 October 2009, 7:10am

For many people map reading can be a struggle, but for the hundreds of thousands that are colour-blind it can be an even more arduous experience.

The traditional rainbow of cartographic colours – green for grass-land and trees, red for main roads and public footpaths, and blue for motorways and rivers – can become indistinguishable, therefore making map reading extremely difficult.

Help may be on the way though, thanks to a new product from mapping agency Ordnance Survey that can be specifically styled to make mapping easier on the colour-blind eye.

Colour blindness is the result of damage to the specialised “cone” cells in the eye which make colour vision possible. It is the most common genetic disorder among humans, afflicting mostly men, with around 8% unable to tell the difference between reds and greens. Instead these colours appear as shades of grey or brown, making it difficulty to interpret the colour coded features shown on maps.

The new Ordnance Survey digital mapping has been developed to be customisable, allowing for the creation of colour-blind-friendly styles, which to most people will look very strange but could help avoid future confusion for those with the condition.

Paul Beauchamp, Ordnance Survey spokesman, comments: “Cartography is a fine art, but the colours that have become so familiar to most of us are actually among the worst possible choices for those with colour blindness. By using our new mapping product, called OS VectorMap Local, councils and businesses will be able to create styles especially for colour-blind people that we hope will make life easier.”

Colour vision deficiency can have an impact on many everyday tasks that most people take for granted – from reading maps, using the Internet and rewiring a plug to knowing when traffic lights change. It can even affect career choices, with pilots and coastguards requiring excellent colour vision.

Geo: International