http://colorvisiontesting.com/ishihara.htm
285 million people are estimated to be visually impaired worldwide: 39 million are blind and 246 have low vision
http://www.who.int/mediacentre/factsheets/fs282/en/
Over 5% of the world’s population – 360 million people – has disabling hearing loss (328 million adults and 32 million children). Disabling hearing loss refers to hearing loss greater than 40 decibels (dB) in the better hearing ear in adults and a hearing loss greater than 30 dB in the better hearing ear in children.
http://www.who.int/mediacentre/factsheets/fs300/en/
Universal design (often inclusive design) refers to broad-spectrum ideas meant to produce buildings, products and environments that are inherently accessible to older people, people without disabilities, and people with disabilities.