Exactly.
SC 1.4.1 Use of Color: Color is not used as the only
visual means of conveying information, indicating an
action, prompting a response, or distinguishing a visual
element. (Level A)
Users who have color-blindness benefit when information
conveyed by color is available in other visual ways.
http://www.w3.org/TR/UNDERSTANDING-WCAG20/visual-audio-contr...