Colorblind Traffic Signals, USA

Industrialization has caused our infrastructure around the world to become dependent on machine-powered transportation, most commonly cars. When driving, traditional red, yellow, and green traffic lights pose challenges for colorblind individuals, especially those who are red-green colorblind. 

In response to this, the first Convention on the Unification of Road Signals was signed in 1931. This caused traffic lights to use standardized positions of red on top and green on the bottom for vertical oriented lights, or red to the right and green to the left for horizontal oriented lights. This makes it so drivers can recognize signals based on placement rather than color. Certain traffic lights also have distinct shapes such as arrows or borders to distinguish colors more effectively. 

These adaptations reflect the importance of design focused on inclusivity and universal accessibility. It remains important to ensure that those with color vision impairments can stay safe in a diverse population.