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NSA ICT 

ACCESSIBILITY

STANDARDS

May 31, 2021

Applicability

• These requirements apply to all web or web-interface applications, whether 

developed in-house, adopted for use, or procured for use within NSA or use by 

NSA affiliates. 

• GUI interfaces should follow the requirements where applicable.

Background

These requirements reflect the Web Content Accessibility Guidelines (WCAG) 2.1 — a stable, 

referenceable, international, technical standard. WCAG 2.1 is part of a series of accessibility 

guidelines, including the Authoring Tool Accessibility Guidelines (ATAG) and the User Agent 

Accessibility Guidelines (UAAG). These documents are developed by the Web Content 

Accessibility Guidelines Working Group (WCAG WG), which is part of the World Wide Web 

Consortium (W3C) Web Accessibility Initiative (WAI). The W3C WAI provides an international 

forum for collaboration between industry, disability organizations, accessibility researchers, 

government, and others interested in web accessibility. The W3C Web Content Accessibility 

Guidelines are the standards referenced by Section 508 of the Federal Rehabilitation for 

compliance with Federal accessibility requirements.

Exceptions

Exceptions and waivers to these requirements may only be granted by the NSA Chief 

Information Officer (CIO) in consultation with Directorate and Independent Office Heads, the 

Office of Equal Employment Opportunity and Diversity, and the Office of General Counsel.
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Principle 1: Perceivable - Information and user interface 

components must be presentable to users in ways they can 

perceive.

Guideline 1.1 Text Alternatives: Provide text alternatives for any non-text content 

so that it can be changed into other forms people need, such as large print, braille, 

speech, symbols or simpler language.

1.1.1 Non-text Content: All non-text content that is presented to the user has a text alternative

that serves the equivalent purpose, except for the situations listed below. 

• Controls, Input: If non-text content is a control or accepts user input, then it has a name

that describes its purpose. (Refer to Guideline 4.1 for additional requirements for 

controls and content that accepts user input.) 

• Time-Based Media: If non-text content is time-based media, then text alternatives at 

least provide descriptive identification of the non-text content. (Refer to Guideline 1.2

for additional requirements for media.) 

• Test: If non-text content is a test or exercise that would be invalid if presented in text, 

then text alternatives at least provide descriptive identification of the non-text content. 

• Sensory: If non-text content is primarily intended to create a specific sensory 

experience, then text alternatives at least provide descriptive identification of the nontext content. 

• CAPTCHA: CAPTCHAs should not be used.

• Decoration, Formatting, Invisible: If non-text content is pure decoration, is used only 

for visual formatting, or is not presented to users, then it is implemented in a way that it 

can be ignored by assistive technology.

Guideline 1.2 Time-based Media: Provide alternatives for time-based media.

1.2.1 Audio-only and Video-only (Prerecorded): For prerecorded audio-only and prerecorded 

video-only media, the following are true, except when the audio or video is a media alternative 

for text and is clearly labeled as such: 

• Prerecorded Audio-only: An alternative for time-based media is provided that presents 

equivalent information for prerecorded audio-only content.

• Prerecorded Video-only: Either an alternative for time-based media or an audio track is 

provided that presents equivalent information for prerecorded video-only content.
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1.2.2 Captions (Prerecorded): Captions are provided for all prerecorded audio content in 

synchronized media, except when the media is a media alternative for text and is clearly 

labeled as such. 

1.2.3 Audio Description or Media Alternative (Prerecorded): An alternative for time-based 

media or audio description of the prerecorded video content is provided for synchronized 

media, except when the media is a media alternative for text and is clearly labeled as such. 

1.2.4 Captions (Live): Captions are provided for all live audio content in synchronized media. 

1.2.8 Media Alternative (Prerecorded): An alternative for time-based media is provided for all 

prerecorded synchronized media and for all prerecorded video-only media. 

Guideline 1.3 Adaptable: Create content that can be presented in different ways 

(for example simpler layout) without losing information or structure.

1.3.1 Info and Relationships: Information, structure, and relationships conveyed through 

presentation can be programmatically determined or are available in text. 

1.3.2 Meaningful Sequence: When the sequence in which content is presented affects its 

meaning, a correct reading sequence can be programmatically determined. 

1.3.3 Sensory Characteristics: Instructions provided for understanding and operating content 

do not rely solely on sensory characteristics of components such as shape, size, visual location, 

orientation, or sound. 

Note: For requirements related to color, refer to Guideline 1.4.

1.3.4 Orientation: Content does not restrict its view and operation to a single display 

orientation, such as portrait or landscape, unless a specific display orientation is essential.

Note: Examples where a particular display orientation may be essential are a bank check, a 

piano application, slides for a projector or television, or virtual reality content where binary 

display orientation is not applicable.

1.3.5 Identify Input Purpose: The purpose of each input field collecting information about the 

user can be programmatically determined when:

• The input field serves a purpose identified in the Input Purposes for User Interface 

Components section; and
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• The content is implemented using technologies with support for identifying the 

expected meaning for form input data.

Guideline 1.4 Distinguishable: Make it easier for users to see and hear content 

including separating foreground from background. 

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. 

Note: This success criterion addresses color perception specifically. Other forms of perception 

are covered in Guideline 1.3 including programmatic access to color and other visual 

presentation coding.

1.4.2 Audio Control: If any audio on a Web page plays automatically for more than 3 seconds, 

either a mechanism is available to pause or stop the audio, or a mechanism is available to 

control audio volume independently from the overall system volume level. 

Note: Since any content that does not meet this success criterion can interfere with a user's 

ability to use the whole page, all content on the Web page (whether or not it is used to meet 

other success criteria) must meet this success criterion. See Conformance Requirement 5: NonInterference.

1.4.3 Contrast (Minimum): The visual presentation of text and images of text has a contrast 

ratio of at least 4.5:1, except for the following: 

• Large Text: Large-scale text and images of large-scale text have a contrast ratio of at 

least 3:1;

• Incidental: 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.

• Logotypes: Text that is part of a logo or brand name has no minimum contrast 

requirement.

1.4.4 Resize text: Except for captions and images of text, text can be resized without assistive 

technology up to 200 percent without loss of content or functionality. 

1.4.5 Images of Text: If the technologies being used can achieve the visual presentation, text is 

used to convey information rather than images of text except for the following: 

• Customizable: The image of text can be visually customized to the user's requirements;
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• Essential: A particular presentation of text is essential to the information being 

conveyed.

Note: Logotypes (text that is part of a logo or brand name) are considered essential.

1.4.10 Reflow: Content can be presented without loss of information or functionality, and 

without requiring scrolling in two dimensions for:

• Vertical scrolling content at a width equivalent to 320 CSS pixels;

• Horizontal scrolling content at a height equivalent to 256 CSS pixels.

Except for parts of the content which require two-dimensional layout for usage or meaning.

Note: 320 CSS pixels is equivalent to a starting viewport width of 1280 CSS pixels wide at 400% 

zoom. For web content which are designed to scroll horizontally (e.g. with vertical text), the 256 

CSS pixels is equivalent to a starting viewport height of 1024px at 400% zoom.

Note: Examples of content which require two-dimensional layout are images, maps, diagrams, 

video, games, presentations, data tables, and interfaces where it is necessary to keep toolbars 

in view while manipulating content.

1.4.11 Non-text Contrast: The visual presentation of the following have a contrast ratio of at 

least 3:1 against adjacent color(s):

• User Interface Components - Visual information required to identify user interface 

components and states, except for inactive components or where the appearance of the 

component is determined by the user agent and not modified by the author;

• Graphical Objects - Parts of graphics required to understand the content, except when a 

particular presentation of graphics is essential to the information being conveyed.

1.4.12 Text Spacing: In content implemented using markup languages that support the 

following text style properties, no loss of content or functionality occurs by setting all of the 

following and by changing no other style property:

• Line height (line spacing) to at least 1.5 times the font size;

• Spacing following paragraphs to at least 2 times the font size;

• Letter spacing (tracking) to at least 0.12 times the font size;

• Word spacing to at least 0.16 times the font size.

Exception: Human languages and scripts that do not make use of one or more of these text 

style properties in written text can conform using only the properties that exist for that 

combination of language and script.
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1.4.13 Content on Hover or Focus: Where receiving and then removing pointer hover or 

keyboard focus triggers additional content to become visible and then hidden, the following are 

true:

• Dismissable - A mechanism is available to dismiss the additional content without 

moving pointer hover or keyboard focus, unless the additional content communicates 

an input error or does not obscure or replace other content;

• Hoverable - If pointer hover can trigger the additional content, then the pointer can be 

moved over the additional content without the additional content disappearing;

• Persistent - The additional content remains visible until the hover or focus trigger is 

removed, the user dismisses it, or its information is no longer valid.

Exception: The visual presentation of the additional content is controlled by the user agent and 

is not modified by the author.

Note: Examples of additional content controlled by the user agent include browser tooltips 

created through use of the HTML title attribute.

Note: Custom tooltips, sub-menus, and other nonmodal popups that display on hover and focus 

are examples of additional content covered by this criterion.
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Principle 2: Operable - User interface components and 

navigation must be operable.

Guideline 2.1 Keyboard Accessible: Make all functionality available from a 

keyboard. 

2.1.1 Keyboard: All functionality of the content is operable through a keyboard interface

without requiring specific timings for individual keystrokes, except where the underlying 

function requires input that depends on the path of the user's movement and not just the 

endpoints. 

Note 1: This exception relates to the underlying function, not the input technique. For example, 

if using handwriting to enter text, the input technique (handwriting) requires path-dependent 

input but the underlying function (text input) does not.

Note 2: This does not forbid and should not discourage providing mouse input or other input 

methods in addition to keyboard operation.

2.1.2 No Keyboard Trap: If keyboard focus can be moved to a component of the page using a 

keyboard interface, then focus can be moved away from that component using only a keyboard 

interface, and, if it requires more than unmodified arrow or tab keys or other standard exit

methods, the user is advised of the method for moving focus away. 

Note: Since any content that does not meet this success criterion can interfere with a user's 

ability to use the whole page, all content on the Web page (whether it is used to meet other 

success criteria or not) must meet this success criterion. See Conformance Requirement 5: NonInterference.

2.1.4 Character Key Shortcuts: If a keyboard shortcut is implemented in content using only 

letter (including upper- and lower-case letters), punctuation, number, or symbol characters, 

then at least one of the following is true:

• Turn off - A mechanism is available to turn the shortcut off;

• Remap - A mechanism is available to remap the shortcut to use one or more nonprintable keyboard characters (e.g. Ctrl, Alt, etc.);

• Active only on focus - The keyboard shortcut for a user interface component is only 

active when that component has focus.
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Guideline 2.2 Enough Time: Provide users enough time to read and use content. 

2.2.1 Timing Adjustable: For each time limit that is set by the content, at least one of the 

following is true: 

• Turn off: The user is allowed to turn off the time limit before encountering it; or 

• Adjust: The user is allowed to adjust the time limit before encountering it over a wide 

range that is at least ten times the length of the default setting; or

• Extend: The user is warned before time expires and given at least 20 seconds to extend 

the time limit with a simple action (for example, "press the space bar"), and the user is 

allowed to extend the time limit at least ten times; or

• Real-time Exception: The time limit is a required part of a real-time event (for example, 

an auction), and no alternative to the time limit is possible; or

• Essential Exception: The time limit is essential and extending it would invalidate the 

activity; or 

• 20 Hour Exception: The time limit is longer than 20 hours. 

Note: This success criterion helps ensure that users can complete tasks without unexpected 

changes in content or context that are a result of a time limit. This success criterion should be 

considered in conjunction with Success Criterion 3.2.1, which puts limits on changes of content 

or context as a result of user action.

2.2.2 Pause, Stop, Hide: For moving, blinking, scrolling, or auto-updating information, all of the 

following are true: 

• Moving, blinking, scrolling: For any moving, blinking or scrolling information that (1) 

starts automatically, (2) lasts more than five seconds, and (3) is presented in parallel 

with other content, there is a mechanism for the user to pause, stop, or hide it unless 

the movement, blinking, or scrolling is part of an activity where it is essential; and

• Auto-updating: For any auto-updating information that (1) starts automatically and (2) 

is presented in parallel with other content, there is a mechanism for the user to pause, 

stop, or hide it or to control the frequency of the update unless the auto-updating is 

part of an activity where it is essential.

Note 1: For requirements related to flickering or flashing content, refer to Guideline 2.3.

Note 2: Since any content that does not meet this success criterion can interfere with a user's 

ability to use the whole page, all content on the Web page (whether it is used to meet other 

success criteria or not) must meet this success criterion. See Conformance Requirement 5: NonInterference.
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Note 3: Content that is updated periodically by software or that is streamed to the user agent is 

not required to preserve or present information that is generated or received between the 

initiation of the pause and resuming presentation, as this may not be technically possible, and 

in many situations could be misleading to do so. 

Note 4: An animation that occurs as part of a preload phase or similar situation can be 

considered essential if interaction cannot occur during that phase for all users and if not 

indicating progress could confuse users or cause them to think that content was frozen or 

broken.

Guideline 2.3 Seizures and Physical Reactions: Do not design content in a way that 

is known to cause seizures or physical reactions.

2.3.1 Three Flashes or Below Threshold: Web pages do not contain anything that flashes more 

than three times in any one second period, or the flash is below the general flash and red flash 

thresholds. 

Note: Since any content that does not meet this success criterion can interfere with a user's 

ability to use the whole page, all content on the Web page (whether it is used to meet other 

success criteria or not) must meet this success criterion. See Conformance Requirement 5: NonInterference.

Guideline 2.4 Navigable: Provide ways to help users navigate, find content, and 

determine where they are. 

2.4.1 Bypass Blocks: A mechanism is available to bypass blocks of content that are repeated on 

multiple Web pages. 

Note: This section shall not apply to any content required for legal or compliance reasons (i.e. 

consent to monitor, user agreements, etc...).

2.4.2 Page Titled: Web pages have titles that describe topic or purpose. 

2.4.3 Focus Order: If a Web page can be navigated sequentially and the navigation sequences 

affect meaning or operation, focusable components receive focus in an order that preserves 

meaning and operability. 
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2.4.4 Link Purpose (In Context): The purpose of each link can be determined from the link text 

alone or from the link text together with its programmatically determined link context, except 

where the purpose of the link would be ambiguous to users in general. 

2.4.5 Multiple Ways: More than one way is available to locate a Web page within a set of Web 

pages except where the Web Page is the result of, or a step in, a process. 

2.4.6 Headings and Labels: Headings and labels describe topic or purpose. 

2.4.7 Focus Visible: Any keyboard operable user interface has a mode of operation where the 

keyboard focus indicator is visible. 

Guideline 2.5 Input Modalities: Make it easier for users to operate functionality 

through various inputs beyond keyboard.

2.5.1 Pointer Gestures: All functionality that uses multipoint or path-based gestures for 

operation can be operated with a single pointer without a path-based gesture, unless a 

multipoint or path-based gesture is essential.

Note: This requirement applies to web content that interprets pointer actions (i.e. this does not 

apply to actions that are required to operate the user agent or assistive technology).

2.5.2 Pointer Cancellation: For functionality that can be operated using a single pointer, at least 

one of the following is true:

• No Down-Event: The down-event of the pointer is not used to execute any part of the 

function;

• Abort or Undo: Completion of the function is on the up-event, and a mechanism is 

available to abort the function before completion or to undo the function after 

completion;

• Up Reversal: The up-event reverses any outcome of the preceding down-event;

• Essential: Completing the function on the down-event is essential.

Note: Functions that emulate a keyboard or numeric keypad key press are considered essential.

Note: This requirement applies to web content that interprets pointer actions (i.e. this does not 

apply to actions that are required to operate the user agent or assistive technology).

2.5.3 Label in Name: For user interface components with labels that include text or images of 

text, the name contains the text that is presented visually.
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Note: A best practice is to have the text of the label at the start of the name.

2.5.4 Motion Actuation: Functionality that can be operated by device motion or user motion 

can also be operated by user interface components and responding to the motion can be 

disabled to prevent accidental actuation, except when:

• Supported Interface: The motion is used to operate functionality through an 

accessibility supported interface;

• Essential: The motion is essential for the function and doing so would invalidate the 

activity.
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Principle 3: Understandable - Information and the operation 

of user interface must be understandable.

Guideline 3.1 Readable: Make text content readable and understandable. 

3.1.1 Language of Page: The default human language of each Web page can be 

programmatically determined. 

3.1.2 Language of Parts: The human language of each passage or phrase in the content can be 

programmatically determined except for proper names, technical terms, words of 

indeterminate language, and words or phrases that have become part of the vernacular of the 

immediately surrounding text. 

Note: In addition to the general exception for collected content, this requirement will not apply 

to any content derived from collected content.

Guideline 3.2 Predictable: Make Web pages appear and operate in predictable 

ways. 

3.2.1 On Focus: When any component receives focus, it does not initiate a change of context. 

3.2.2 On Input: Changing the setting of any user interface component does not automatically 

cause a change of context unless the user has been advised of the behavior before using the 

component. 

3.2.3 Consistent Navigation: Navigational mechanisms that are repeated on multiple Web 

pages within a set of Web pages occur in the same relative order each time they are repeated, 

unless a change is initiated by the user. 

3.2.4 Consistent Identification: Components that have the same functionality within a set of 

Web pages are identified consistently. 

Guideline 3.3 Input Assistance: Help users avoid and correct mistakes. 

3.3.1 Error Identification: If an input error is automatically detected, the item that is in error is 

identified and the error is described to the user in text. 
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3.3.2 Labels or Instructions: Labels or instructions are provided when content requires user 

input. 

3.3.3 Error Suggestion: If an input error is automatically detected and suggestions for 

correction are known, then the suggestions are provided to the user, unless it would jeopardize 

the security or purpose of the content. 

3.3.4 Error Prevention (Legal, Financial, Data): For Web pages that cause legal commitments or 

financial transactions for the user to occur, that modify or delete user-controllable data in data 

storage systems, or that submit user test responses, at least one of the following is true: 

• Reversible: Submissions are reversible.

• Checked: Data entered by the user is checked for input errors and the user is provided 

an opportunity to correct them.

• Confirmed: A mechanism is available for reviewing, confirming, and correcting 

information before finalizing the submission.
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Principle 4: Robust - Content must be robust enough that it can 

be interpreted reliably by a wide variety of user agents, 

including assistive technologies.

Guideline 4.1 Compatible: Maximize compatibility with current and future user 

agents, including assistive technologies.

4.1.1 Parsing: In content implemented using markup languages, elements have complete start 

and end tags, elements are nested according to their specifications, elements do not contain 

duplicate attributes, and any IDs are unique, except where the specifications allow these 

features. 

Note: Start and end tags that are missing a critical character in their formation, such as a closing 

angle bracket or a mismatched attribute value quotation mark are not complete.

4.1.2 Name, Role, Value: For all user interface components (including but not limited to: form 

elements, links and components generated by scripts), the name and role can be 

programmatically determined; states, properties, and values that can be set by the user can be 

programmatically set; and notification of changes to these items is available to user agents, 

including assistive technologies. 

Note: This success criterion is primarily for Web authors who develop or script their own user 

interface components. For example, standard HTML controls already meet this success criterion 

when used according to specification.

4.1.3 Status Messages: In content implemented using markup languages, status messages can 

be programmatically determined through role or properties such that they can be presented to 

the user by assistive technologies without receiving focus.
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Additional Guidelines

These are additional guidelines drawn from WCAG. They are considered good practice, but are 

not mandatory. (For ease of reference, the original WCAG numbering has been retained.)

1.2.5 Audio Description (Prerecorded): Audio description is provided for all prerecorded video

content in synchronized media. 

1.2.6 Sign Language (Prerecorded): Sign language interpretation is provided for all prerecorded

audio content in synchronized media. 

1.2.7 Extended Audio Description (Prerecorded): Where pauses in foreground audio are 

insufficient to allow audio descriptions to convey the sense of the video, extended audio 

description is provided for all prerecorded video content in synchronized media. 

1.2.9 Audio-only (Live): An alternative for time-based media that presents equivalent 

information for live audio-only content is provided. 

1.3.6 Identify Purpose: In content implemented using markup languages, the purpose of User 

Interface Components, icons, and regions can be programmatically determined.

1.4.6 Contrast (Enhanced): The visual presentation of text and images of text has a contrast 

ratio of at least 7:1, except for the following: 

• Large Text: Large-scale text and images of large-scale text have a contrast ratio of at 

least 4.5:1;

• Incidental: 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.

• Logotypes: Text that is part of a logo or brand name has no minimum contrast 

requirement.

1.4.7 Low or No Background Audio: For prerecorded audio-only content that (1) contains 

primarily speech in the foreground, (2) is not an audio CAPTCHA or audio logo, and (3) is not 

vocalization intended to be primarily musical expression such as singing or rapping, at least one 

of the following is true: 

• No Background: The audio does not contain background sounds.

• Turn Off: The background sounds can be turned off.

• 20 dB: The background sounds are at least 20 decibels lower than the foreground 

speech content, with the exception of occasional sounds that last for only one or two 

seconds.
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Note: Per the definition of "decibel," background sound that meets this requirement will be 

approximately four times quieter than the foreground speech content. 

1.4.8 Visual Presentation: For the visual presentation of blocks of text, a mechanism is available 

to achieve the following: 

1. Foreground and background colors can be selected by the user.

2. Width is no more than 80 characters or glyphs (40 if Chinese, Japanese, Korean).

3. Text is not justified (aligned to both the left and the right margins).

4. Line spacing (leading) is at least space-and-a-half within paragraphs, and paragraph 

spacing is at least 1.5 times larger than the line spacing.

5. Text can be resized without assistive technology up to 200 percent in a way that does 

not require the user to scroll horizontally to read a line of text on a full-screen window.

Note: This does not apply to any text where white-space conveys information, or a contextappropriate style guide clearly specifies where whitespace and line-breaks should be used.

1.4.9 Images of Text (No Exception): Images of text are only used for pure decoration or where 

a particular presentation of text is essential to the information being conveyed. 

Note: Logotypes (text that is part of a logo or brand name) are considered essential.

2.1.3 Keyboard (No Exception): All functionality of the content is operable through a keyboard 

interface without requiring specific timings for individual keystrokes. 

2.2.3 No Timing: Timing is not an essential part of the event or activity presented by the 

content, except for non-interactive synchronized media and real-time events. 

2.2.4 Interruptions: Interruptions can be postponed or suppressed by the user, except 

interruptions involving an emergency. 

2.2.5 Re-authenticating: When an authenticated session expires, the user can continue the 

activity without loss of data after re-authenticating. 

2.2.6 Timeouts: Users are warned of the duration of any user inactivity that could cause data 

loss, unless the data is preserved for more than 20 hours when the user does not take any 

actions.

2.3.2 Three Flashes: Web pages do not contain anything that flashes more than three times in 

any one second period. 

2.3.3 Animation from Interactions: Motion animation triggered by interaction can be disabled, 

unless the animation is essential to the functionality or the information being conveyed.
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2.4.8 Location: Information about the user's location within a set of Web pages is available. 

2.4.9 Link Purpose (Link Only): A mechanism is available to allow the purpose of each link to be 

identified from link text alone, except where the purpose of the link would be ambiguous to 

users in general. 

2.4.10 Section Headings: Section headings are used to organize the content. 

Note 1: "Heading" is used in its general sense and includes titles and other ways to add a 

heading to different types of content. 

Note 2: This success criterion covers sections within writing, not user interface components. 

User Interface components are covered under Success Criterion 4.1.2.

2.5.5 Target Size: The size of the target for pointer inputs is at least 44 by 44 CSS pixels except 

when:

• Equivalent - The target is available through an equivalent link or control on the same 

page that is at least 44 by 44 CSS pixels;

• Inline - The target is in a sentence or block of text;

• User Agent Control - The size of the target is determined by the user agent and is not 

modified by the author;

• Essential - A particular presentation of the target is essential to the information being 

conveyed.

2.5.6 Concurrent Input Mechanisms: Web content does not restrict use of input modalities 

available on a platform except where the restriction is essential, required to ensure the security 

of the content, or required to respect user settings.

3.1.3 Unusual Words: A mechanism is available for identifying specific definitions of words or 

phrases used in an unusual or restricted way, including idioms and jargon. 

3.1.4 Abbreviations: A mechanism for identifying the expanded form or meaning of 

abbreviations is available. 

3.1.5 Reading Level: When text requires reading ability more advanced than the lower 

secondary education level after removal of proper names and titles, supplemental content, or a 

version that does not require reading ability more advanced than the lower secondary 

education level, is available. 

3.1.6 Pronunciation: A mechanism is available for identifying specific pronunciation of words 

where meaning of the words, in context, is ambiguous without knowing the pronunciation. 
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3.2.5 Change on Request: Changes of context are initiated only by user request or a mechanism

is available to turn off such changes. 

3.3.5 Help: Context-sensitive help is available. 

3.3.6 Error Prevention (All): For Web pages that require the user to submit information, at least 

one of the following is true: 

1. Reversible: Submissions are reversible.

2. Checked: Data entered by the user is checked for input errors and the user is provided 

an opportunity to correct them.

3. Confirmed: A mechanism is available for reviewing, confirming, and correcting 

information before finalizing the submission.