Provide an alternative to each CAPTCHA that is only a sound or only a visual test
For each CAPTCHA (anti-spam system) that is only a sound or only a visual test, an alternative must be provided.
- A sound alternative.
- A text alternative in the form of a simple or mathematical question.
For each CAPTCHA, it is highly recommended to provide a way to refresh its content because it happens very regularly that the CAPTCHA cannot be deciphered at the first reading.
Good practice is to provide, in addition to the reload solution, information on how to contact the website manager, if the CAPTCHA cannot be typed in (a link to the “Contact” page, a phone number, etc.).
CAPTCHAs are designed to block spambots that use more and more sophisticated techniques to circumvent them.
CAPTCHAs are therefore more and more complicated to decipher.
By definition, a CAPTCHA will never be fully accessible, so the best solution to ensure accessibility is to do without it or to prefer security tests presented as logical tests.