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Notes around contrast ratio and web accessibility standards
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DaVita must follow WCAG AA 2.0 guidlines to stay in compliance
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In order to meet the guidelines at Level AA, text or images of text must have a contrast ratio of at least 4.5:1 or 3:1 for large text.
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Success Criterion (SC)
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The visual presentation of text and images of text has a contrast ratio of at least 4.5:1, except for the following:
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Large Text
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Large-scale text and images of large-scale text have a contrast ratio of at least 3:1;
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Incidental
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Text or images of text that are part of an inactive user interface component, that are pure decoration, that are not visible to anyone, or that are part of a picture that contains significant other visual content, have no contrast requirement.
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Logotypes
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Text that is part of a logo or brand name has no contrast requirement.
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Infographics/Text Images
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The contrast requirements for text also apply to images of text (text that has been rendered into pixels and then stored in an image format)
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Inactive User Interface Components
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User Interface Components that are not available for user interaction (e.g., a disabled control in HTML) are not required to meet contrast requirements. An inactive user interface component is visible but not currently operable. An example would be a submit button at the bottom of a form that is visible but cannot be activated until all the required fields in the form are completed.
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Tool used to measure contrast ratios in this document
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https://www.whocanuse.com/
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