> The United States is the only country that prints all denominations of currency in the same size. The US and Switzerland are the only two countries that use the same colors for all of their various bills. Needless to say, this sameness of size and color make it impossible for a blind person to locate the correct bills to make a purchase without some sort of assistance, or confirm that he or she has been given the correct change by the sales clerk. Even people with partial sight may have trouble distinguishing a $1 bill from a $10, especially if the bill is old and worn.
https://afb.org/blindness-and-low-vision/using-technology/ac...