EPUB Accessibility Metadata Examples

Preprocessing

Before working directly with the metadata we must read the metadata in the Package document (package document) inside the EPUB. This is a common starting point for all techniques that allows us to query the metadata directly.

This algorithm takes the package_document_as_text argument: a UTF-8 string representing the Package document.

To generate the internal representation, run the following steps:

1. LET package_document_content be textual representation of the Package document for the publication given package_document_as_text.
2. LET package_document be the DOM tree that results from parsing package_document_content using an XML DOM parser.
3. Return package_document.

Check for Node

Many of the techniques rely on checking for the presence or absence of metadata in the metadata section of the Package document.

This algorithm takes:

• the package_document argument: the internal representation of the Package document (output of preprocessing);
• the path argument: the XPATH of the node to check the presence of.

To check for node, run the following steps:

1. IF package_document contains path: THEN return True.
2. ELSE return False.

Join array to comma list

This function serves to concatenate an array of strings, separating each element with a comma, with the last element separated by an ", and" (this string is localizable).

For example if the input array has elements ["one", "two", "three"], then the output is going to be "one, two, and three".

This algorithm takes the string_array argument: the list of string to join.

To join the array, run the following steps:

1. LET output_string be the result of:
   • calling join on string_array with the separator ", "
   • replacing the last occurrence of ", " with ", and ".
2. return output_string.

Visual adjustments

This technique relates to Visual adjustments key information.

This algorithm takes the package_document_as_text argument: a UTF-8 string representing the Package document.

Understanding the variables

all_textual_content_can_be_modified

If true it indicates that the accessibilityFeature="displayTransformability" (All textual content can be modified) is present in the package document, otherwise if false it means that the metadata is not present.

All textual content can be modified means that the digital publication does not restrict the ability of users to modify and reflow the display of any textual content to the full extent allowed by the reading system (i.e. to change the text size or typeface, line height and word spacing, colors).

is_fixed_layout

If true it indicates that the layout="pre-paginated" (Fixed format) is present in the package document, otherwise if false it means that the metadata is not present.

Fixed format means that digital publication is in fixed format (e.g. EPUB Fixed Layout).

Variables setup

1. LET package_document be the result of calling preprocessing given package_document_as_text.
2. LET all_textual_content_can_be_modified be the result of calling check for node on package_document, /package/metadata/meta[@property="schema:accessibilityFeature" and text()="displayTransformability"].
3. LET is_fixed_layout be the result of calling check for node on package_document, /package/metadata/meta[@property="rendition:layout" and text()="pre-paginated"].

Instructions

1. Display "Visual adjustments" as heading.
2. IF all_textual_content_can_be_modified: THEN display "Appearance can be modified".
3. ELSE IF is_fixed_layout: THEN display "Appearance cannot be modified".
4. ELSE display "Appearance modifiability not known".

Supports nonvisual reading

This technique relates to Supports nonvisual reading key information.

This algorithm takes the package_document_as_text argument: a UTF-8 string representing the Package document.

Understanding the variables

all_necessary_content_textual

If true it indicates that the accessModeSufficient="textual" (all main content is provided in textual form) is present in the package document, otherwise if false it means that the metadata is not present.

All non-decorative content supports reading without sight means that all contents of the digital publication necessary to use and understanding, including text, images (via their alternative descriptions), audio and video material (via their transcripts, descriptions, captions or subtitles) are fully accessible via suitable reading devices, for example text-to-speech screen readers or tactile reading devices (‘Braille displays’), and nothing in the digital publication prevents or blocks the use of alternative reading modes. The entire publication can be navigated and ‘read’ using only text rendered via sound or touch, and does not require visual perception.

non_textual_content_images

If true it indicates that at least one of the following is present in the package document:

• accessMode="chartOnVisual" (Charts and Graphs);
• accessMode="chemOnVisual" (Chemistry);
• accessMode="diagramOnVisual" (Diagrams);
• accessMode="mathOnVisual" (Math);
• accessMode="musicOnVisual" (Music);
• accessMode="textOnVisual" (Images of text);
• otherwise if false it means that this metadata is not present.

This means that the content contains images of any type.

textual_alternative_images

If true it indicates that at least one of the following is present in the package document:

• accessibilityFeature="alternativeText" (Short alternative textual descriptions);
• accessibilityFeature="longDescription" (Full alternative textual descriptions);
• accessibilityFeature="describedMath" (Visual of math fully described));
• otherwise if false it means that this metadata is not present.

This means that there are textual alternatives for images.

Variables setup

1. LET package_document be the result of calling preprocessing given package_document_as_text.
2. LET all_necessary_content_textual be the result of calling check for node on package_document, /package/metadata/meta[@property="schema:accessModeSufficient" and text()="textual"].
3. LET non_textual_content_images be the result of calling check for node on package_document, /package/metadata/meta[@property="schema:accessibilityFeature" and
(text()="chartOnVisual" or text()="chemOnVisual" or
text()="diagramOnVisual" or text()="mathOnVisual" or
text()="musicOnVisual" or text()="textOnVisual")].
4. LET textual_alternative_images be the result of calling check for node on package_document, /package/metadata/meta[@property="schema:accessibilityFeature" and
(text()="longDescription" or text()="alternativeText" or text()="describedMath")].

Instructions

1. Display "Supports nonvisual reading" as heading.
2. IF all_necessary_content_textual: THEN display "Readable in read aloud or dynamic braille".
3. ELSE IF non_textual_content_images AND NOT textual_alternative_images: THEN display "Not fully readable in read aloud or dynamic braille".
4. ELSE display "May not be fully readable in read aloud or dynamic braille".

Conformance

This technique relates to Conformance key information.

This algorithm takes the package_document_as_text argument: a UTF-8 string representing the Package document.

Understanding the variables

epub_accessibility_1_0

If true it indicates that the conformsTo="http://www.idpf.org/epub/a11y/accessibility-20170105.html#wcag-a" (EPUB Accessibility Specification 1.0 A) or the conformsTo="http://www.idpf.org/epub/a11y/accessibility-20170105.html#wcag-aa" (EPUB Accessibility Specification 1.0 AA) or the conformsTo="http://www.idpf.org/epub/a11y/accessibility-20170105.html#wcag-aaa" (EPUB Accessibility Specification 1.0 AAA) is present in the package document, otherwise if false it means that the metadata is not present.

This means that the publication conforms with either the requirements of EPUB Accessibility Spec 1.0, at level A, AA, or AAA.

epub_accessibility_1_1

If true it indicates that the conformsTo contains "EPUB Accessibility 1.1" (EPUB Accessibility Specification 1.1) is present in the package document, otherwise if false it means that the metadata is not present.

This means that the publication conforms with the requirements of EPUB Accessibility Spec 1.1.

wcag_20

If true it indicates that the conformsTo contains "WCAG 2.0" or conformsTo="http://www.idpf.org/epub/a11y/accessibility-20170105.html#wcag-a" (EPUB Accessibility Specification 1.0 A) or the conformsTo="http://www.idpf.org/epub/a11y/accessibility-20170105.html#wcag-aa" (EPUB Accessibility Specification 1.0 AA) or the conformsTo="http://www.idpf.org/epub/a11y/accessibility-20170105.html#wcag-aaa" (EPUB Accessibility Specification 1.0 AAA) are present in the package document, otherwise if false it means that the metadata is not present.

This means that the publication conforms with the requirements of WCAG version 2.0 or with the requirements of EPUB Accessibility Spec 1.0 (at level A, AA, or AAA). This is because being compliant with EPUB Accessibility 1.0 specification means at least being compliant with WCAG 2.0 specification.

wcag_21

If true it indicates that the conformsTo contains "WCAG 2.1" is present in the package document, otherwise if false it means that the metadata is not present.

This means that the publication conforms with the requirements of WCAG version 2.1.

wcag_22

If true it indicates that the conformsTo contains "WCAG 2.2" is present in the package document, otherwise if false it means that the metadata is not present.

This means that the publication conforms with the requirements of WCAG version 2.2.

level_a

If true it indicates that the conformsTo contains "Level A" or the conformsTo="http://www.idpf.org/epub/a11y/accessibility-20170105.html#wcag-a" (EPUB Accessibility Specification 1.0 A) are present in the package document, otherwise if false it means that the metadata is not present.

This means that the publication conforms with the requirements of WCAG level A or with the requirements of EPUB Accessibility Spec 1.0 level A.

level_aa

If true it indicates that the conformsTo contains "Level AA" or the conformsTo="http://www.idpf.org/epub/a11y/accessibility-20170105.html#wcag-aa" (EPUB Accessibility Specification 1.0 AA) are present in the package document, otherwise if false it means that the metadata is not present.

This means that the publication conforms with the requirements of WCAG level AA or with the requirements of EPUB Accessibility Spec 1.0 level AA.

level_aaa

If true it indicates that the conformsTo contains "Level AAA" or the conformsTo="http://www.idpf.org/epub/a11y/accessibility-20170105.html#wcag-aaa" (EPUB Accessibility Specification 1.0 A) are present in the package document, otherwise if false it means that the metadata is not present.

This means that the publication conforms with the requirements of WCAG level AAA or with the requirements of EPUB Accessibility Spec 1.0 level AAA.

certifier

Returns the description of a11y:certifiedBy (Compliance certification by (name)) if present in the package document, otherwise if false it means that the metadata is not present.

This means that the name of the organization responsible for compliance testing and certification of the product is present.

certifier_credentials

Returns the description of a11y:certifierCredential (Compliance certification by (URL)) if present in the package document, otherwise if false it means that the metadata is not present.

This means that the the URL of a web page belonging to an organization responsible for compliance testing and certification of the product is present – typically a ‘home page’ or a page describing the certification scheme itself.

certification_date

Returns the description of dcterms:date if that date property is associated with the a11y:certifiedBy (Latest accessibility assessment date) if present in the package document, otherwise if false it means that the metadata is not present.

This means that the date of the latest assessment or re-assessment of the accessibility of the product is present.

certifier_report

Returns the description of a11y:certifierReport (Compliance web page for detailed accessibility information) if present in the OPF, otherwise if false it means that the metadata is not present.

This means that is present the URL of a compliance web page for detailed accessibility information. The web page should be maintained by an independent compliance scheme or testing organization. Note the web page may include information about specific national requirements or voluntary conformance reports.

conformance-claimed

If true it indicates that the conformsTo is present in the package document, otherwise if false it means that the metadata is not present.

This means that the publication conforms to some specification.

Variables setup

1. LET package_document be the result of calling preprocessing given package_document_as_text.
2. LET epub_accessibility_1_0 be the result of calling check for node on package_document, /package/metadata/meta[@property="dcterms:conformsTo" and contains(text(), http://www.idpf.org/epub/a11y/accessibility-20170105.html#wcag-"].
3. LET epub_accessibility_1_1 be the result of calling check for node on package_document, /package/metadata/meta[@property="dcterms:conformsTo" and contains(text(), "EPUB Accessibility 1.1")].
4. LET wcag_20 be the result of calling check for node on package_document, /package/metadata/meta[@property="dcterms:conformsTo" and contains(text(), "http://www.idpf.org/epub/a11y/accessibility-20170105.html#wcag-")] OR calling check for node on package_document, /package/metadata/meta[@property="dcterms:conformsTo" and contains(text(), "WCAG 2.0")]
5. LET wcag_21 be the result of calling check for node on package_document, /package/metadata/meta[@property="dcterms:conformsTo" and contains(text(), WCAG 2.1")].
6. LET wcag_22 be the result of calling check for node on package_document, /package/metadata/meta[@property="dcterms:conformsTo" and contains(text(), WCAG 2.2")].
7. LET level_a be the result of calling check for node on package_document, /package/metadata/meta[@property="dcterms:conformsTo" and contains(text(), Level A")] OR calling check for node on package_document, /package/metadata/meta[@property="dcterms:conformsTo" and text()=http://www.idpf.org/epub/a11y/accessibility-20170105.html#wcag-a"].
8. LET level_aa be the result of calling check for node on package_document, /package/metadata/meta[@property="dcterms:conformsTo" and contains(text(), Level AA")] OR calling check for node on package_document, /package/metadata/meta[@property="dcterms:conformsTo" and text()=http://www.idpf.org/epub/a11y/accessibility-20170105.html#wcag-aa"].
9. LET level_aaa be the result of calling check for node on package_document, /package/metadata/meta[@property="dcterms:conformsTo" and contains(text(), Level AAA")] OR calling check for node on package_document, /package/metadata/meta[@property="dcterms:conformsTo" and text()=http://www.idpf.org/epub/a11y/accessibility-20170105.html#wcag-aaa"].
10. LET certifier be the value of the node extracted from package_document, using the xpath /package/metadata/meta[@property="a11y:certifiedBy"]/text().
11. LET certifier_credentials be the value of the node extracted from package_document, using the xpath /package/metadata/meta[@property="a11y:certifierCredential"]/text().
12. LET certification_date be the value of the node extracted from package_document, using the xpath /package/metadata/meta[@property="dcterms:date" and @refines=//meta[@property="a11y:certifiedBy"]/@id]/text()].
13. LET certifier_report be the value of the node extracted from package_document, using the xpath /package/metadata/meta[@property="a11y:certifierReport"]/text()].
14. LET conformance_claimed be the result of calling check for node on package_document, /package/metadata/meta[@property="dcterms:conformsTo"].

Instructions

1. Display "Conformance" as heading.
2. IF level_aaa: THEN display "This publication exceeds accepted accessibility standards".
3. ELSE IF level_aa: THEN display "This publication meets accepted accessibility standards".
4. ELSE IF level_a: THEN display "This publication meets minimum accessibility standards".
5. ELSE IF conformance_claimed: THEN display "Conformance to accepted standards for accessibility of this publication cannot be determined".
6. ELSE: THEN display "The publication does not include a conformance statement".
7. IF certifier is NOT empty: THEN
   • display "This publication is certified by "
   • display certifier.
8. IF certifier_credentials is NOT empty: THEN
   • display "The certifier's credential is "
   • display certifier_credentials as link IF certifier_credentials is an URL.
9. display "Detailed Conformance Information" as heading.
10. IF epub_accessibility_1_0 OR epub_accessibility_1_1 OR wcag_20 OR wcag_21 OR wcag_22 OR level_aaa OR level_aa OR level_a: THEN display "This publication claims to meet ".
11. IF epub_accessibility_1_0: THEN display " EPUB Accessibility 1.0 ".
12. ELSE IF epub_accessibility_1_1: THEN display " EPUB Accessibility 1.1 ".
13. IF wcag_22: THEN display " WCAG 2.2 ".
14. ELSE IF wcag_21: THEN display " WCAG 2.1 ".
15. ELSE IF wcag_20: THEN display " WCAG 2.0 ".
16. IF level_aaa: THEN display " Level AAA".
17. ELSE IF level_aa: THEN display " Level AA".
18. ELSE IF level_a: THEN display " Level A".
19. IF certification_date OR certifier OR certifier_credentials: THEN display "The publication was certified ".
20. IF certification_date: THEN
    • display " on "
    • display certification_date.
21. IF certifier: THEN
    • display " by "
    • display certifier.
22. IF certifier_credentials: THEN
    • display " with a credential of "
    • display certifier_credentials as link IF certifier_credentials is an URL.
23. IF certifier_report: THEN
    • display "For more information refer to the certifier's report"
    • with certifier_report as link.

Pre-recorded audio

This technique relates to Pre-recorded audio key information.

This algorithm takes the package_document_as_text argument: a UTF-8 string representing the Package document.

Understanding the variables

all_content_audio

If true it indicates that the accessModeSufficient="auditory" (all main content is provided in audio form) is present in the package document, otherwise if false it means that the metadata is not present.

synchronised_pre_recorded_audio

If true it indicates that the accessibilityFeature="sychronizedAudioText" is present in the package document, otherwise, if false, it means that the metadata is not present.

This indicates that text-synchronised pre-recorded audio narration (natural or synthesised voice) is included for substantially all textual matter, including all alternative descriptions, e.g. via a SMIL media overlay.

audio_content

If true it indicates that the accessMode="auditory" is present in the package document, otherwise, if false, it means that the metadata is not present.

This indicates that pre-recorded audio content is included as part of the work.

Variables setup

1. LET package_document be the result of calling preprocessing given package_document_as_text.
2. LET all_content_audio be the result of calling check for node on package_document, /package/metadata/meta[@property="schema:accessModeSufficient" and text()="auditory"].
3. LET synchronised_pre_recorded_audio be the result of calling check for node on package_document, /package/metadata/meta[@property="schema:accessibilityFeature" and text()="sychronizedAudioText"].
4. LET audio_content be the result of calling check for node on package_document, /package/metadata/meta[@property="schema:accessMode" and text()="auditory"].

Instructions

1. Display "Pre-recorded audio" as heading.

   This heading can be hidden if metadata is missing.

2. IF all_content_audio: THEN display "Audio only".
3. ELSE IF synchronised_pre_recorded_audio: THEN display "Synchronized audio and text".
4. ELSE IF audio_content: THEN display "Complementary audio and text".
5. ELSE either omit this key informtion if metadata is missing or display "No information about pre-recorded audio is available.".

Navigation

This technique relates to Navigation key information.

This algorithm takes the package_document_as_text argument: a UTF-8 string representing the Package document.

Understanding the variables

table_of_contents_navigation

If true it indicates that the accessibilityFeature="tableOfContents" (Table of contents navigation) is present in the package document, otherwise if false it means that the metadata is not present.

This means that the resource includes a table of contents that provides links to the major sections of the content.

index_navigation

If true it indicates that the accessibilityFeature="index" (Index navigation) is present in the package document, otherwise if false it means that the metadata is not present.

This means that there is an index that provides direct (eg hyperlinked) access to uses of the index terms in the document body.

page_navigation

If true it indicates that the accessibilityFeature="pageNavigation" (Page Navigation) is present in the package document, otherwise if false it means that the metadata is not present.

This means that the e-publication includes a means of navigating to static page break locations.

next_previous_structural_navigation

If true it indicates that the accessibilityFeature="structuralNavigation" (Next / Previous structural navigation) is present in the package document, otherwise if false it means that the metadata is not present.

This means that all levels of heading and other structural elements of the content are correctly marked up and (if applicable) numbered, to enable fast next heading / previous heading, next chapter / previous chapter navigation without returning to the table of contents.

Variables setup

1. LET package_document be the result of calling preprocessing given package_document_as_text.
2. LET table_of_contents_navigation be the result of calling check for node on package_document, /package/metadata/meta[@property="schema:accessibilityFeature" and text()="tableOfContents"].
3. LET index_navigation be the result of calling check for node on package_document, /package/metadata/meta[@property="schema:accessibilityFeature" and text()="index"].
4. LET page_navigation be the result of calling check for node on package_document, /package/metadata/meta[@property="schema:accessibilityFeature" and text()="pageNavigation"].
5. LET next_previous_structural_navigation be the result of calling check for node on package_document, /package/metadata/meta[@property="schema:accessibilityFeature" and text()="structuralNavigation"].

Instructions

1. Display "Navigation" as heading.

   This heading can be hidden if metadata is missing.

2. IF table_of_contents_navigation OR index_navigation OR print_equivalent_page_numbering OR next_previous_structural_navigation: THEN LET navigation be an empty array.
   1. IF table_of_contents_navigation: THEN APPEND "table of contents" to navigation.
   2. IF index_navigation: THEN APPEND "index" to navigation.
   3. IF page_navigation: THEN APPEND "supports page navigation" to navigation.
   4. IF next_previous_structural_navigation: THEN APPEND "headings" to navigation.
   5. LET navigation_string be the result of:
      • calling join array to comma list given navigation
      • concatenating "Navigation by " to the beginning of the string.
   6. display navigation_string.
3. ELSE either omit this key informtion if metadata is missing or display "No information about navigation is available.".

Charts, diagrams, math, and formulas

This technique relates to Charts, diagrams, math, and formulas key information.

This algorithm takes the package_document_as_text argument: a UTF-8 string representing the Package document.

Understanding the variables

contains_charts_diagrams

If true it indicates that the accessibilityFeature="chartOnVisual" (charts encoded in visual form) is present in the package document, otherwise if false it means that the metadata is not present.

This means that there is a positive indication that the product has some information conveyed via some form of illustration, such as a graph, a chart, a diagram, a figure, etc).

long_text_descriptions

If true it indicates that the accessibilityFeature="longDescriptions" (Full alternative textual description) is present in the package document, otherwise if false it means that the metadata is not present.

This means that there is a positive indication that a full alternative textual description has been supplied for all of the graphs, charts, diagrams, or figures necessary to understand the content.

contains_chemical_formula

If true it indicates that the accessibilityFeature="chemOnVisual" (Chemical content) is present in the package document, otherwise if false it means that the metadata is not present.

This means that there is a positive indication that the publication contains chemical notations, formulae.

chemical_formula_as_chemml

If true it indicates that the accessibilityFeature="ChemML" (Accessible chemistry content as ChemML) is present in the package document, otherwise if false it means that the metadata is not present.

This means that there is a positive indication that the chemical formulae are presented using ChemML and works with compatible assistive technology.

contains_math_formula

If true it indicates that the accessibilityFeature="describedMath" (Mathematical content) is present in the package document, otherwise if false it means that the metadata is not present.

This means that there is a positive indication that the publication contains mathematical notation, equations, formulae.

math_formula_as_latex

If true it indicates that the accessibilityFeature="latex" (Accessible math content as LaTeX) is present in the package document, otherwise if false it means that the metadata is not present.

This means that there is a positive indication that the math is presented using LaTeX and works with compatible assistive technology.

math_formula_as_mathml

If true it indicates that the accessibilityFeature="MathML" (Accessible math content as MathML) is present in the package document, otherwise if false it means that the metadata is not present.

This means that there is a positive indication that all mathematical content is presented using MathML and works with compatible assistive technology.

Variables setup

1. LET package_document be the result of calling preprocessing given package_document_as_text.
2. LET contains_charts_diagrams be the result of calling check for node on package_document, /package/metadata/meta[@property="schema:accessibilityFeature" and text()="chartOnVisual"].
3. LET long_text_descriptions be the result of calling check for node on package_document, /package/metadata/meta[@property="schema:accessibilityFeature" and text()="longDescriptions"].
4. LET contains_chemical_formula be the result of calling check for node on package_document, /package/metadata/meta[@property="schema:accessibilityFeature" and text()="chemOnVisual"].
5. LET chemical_formula_as_chemml be the result of calling check for node on package_document, /package/metadata/meta[@property="schema:accessibilityFeature" and text()="ChemML"].
6. LET contains_math_formula be the result of calling check for node on package_document, /package/metadata/meta[@property="schema:accessibilityFeature" and text()="describedMath"].
7. LET math_formula_as_latex be the result of calling check for node on package_document, /package/metadata/meta[@property="schema:accessibilityFeature" and text()="latex"].
8. LET math_formula_as_mathml be the result of calling check for node on package_document, /package/metadata/meta[@property="schema:accessibilityFeature" and text()="MathML"].

Instructions

1. Display "Charts, diagrams, math, and formulas" as heading.

   This heading can be hidden if metadata is missing.

2. IF (contains_charts_diagrams AND long_text_descriptions): THEN display "Charts and diagrams have extended descriptions".
3. IF chemical_formula_as_chemml: THEN display "Accessible chemistry content".
4. IF math_formula_as_latex OR math_formula_as_mathml: THEN display "Accessible math content".
5. IF (contains_charts_diagrams OR contains_chemical_formula OR contains_math_formula) AND NOT (long_text_descriptions OR chemical_formula_as_chemml OR math_formula_as_latex OR math_formula_as_mathml): THEN display "accessibility of formulas, charts, math, and diagrams not identified as being accessible".

Hazards

This technique relates to Hazards key information.

This algorithm takes the package_document_as_text argument: a UTF-8 string representing the Package document.

Understanding the variables

no_hazards_or_warnings_confirmed

If true it indicates that the accessibilityHazard="none" (no accessibility hazards) is present in the package document, otherwise if false it means that the metadata is not present.

This means there is a positive indication in the accessiblity metadata within the EPUB confirming there are no associated hazard warnings with this product.

flashing_hazard

If true it indicates that the accessibilityHazard="flashing" (WARNING - Flashing hazards) is present in the package document, otherwise if false it means that the metadata is not present.

This means that there is a positive indication in the accessiblity metadata within the EPUB confirming that the product has a flashing hazard which must be displayed.

no_flashing_hazards

If true it indicates that the accessibilityHazard="noFlashingHazard" (No flashing hazard warning necessary) is present in the package document, otherwise if false it means that the metadata is not present.

This means there is a positive indication in the accessiblity metadata within the EPUB confirming there are no flashing hazards associated with this product.

motion_simulation_hazard

If true it indicates that the accessibilityHazard="motionSimulation" (WARNING - Motion simulation hazard) is present in the package document, otherwise if false it means that the metadata is not present.

This means that there is a positive indication in the accessiblity metadata within the EPUB confirming that the product has a motion simulation hazard which must be displayed.

no_motion_hazards

If true it indicates that the accessibilityHazard="noMotionSimulationHazard" (No motion simulation hazard warning necessary) is present in the package document, otherwise if false it means that the metadata is not present.

This means there is a positive indication in the accessiblity metadata within the EPUB confirming there are no motion simulation hazards associated with this product.

sound_hazard

If true it indicates that the accessibilityHazard="Sound" (WARNING - Sound hazard) is present in the package document, otherwise if false it means that the metadata is not present.

This means that there is a positive indication in the accessiblity metadata within the EPUB confirming that the product has a sound hazard which must be displayed.

no_sound_hazards

If true it indicates that the accessibilityHazard="noSoundHazard" (No sound hazard warning necessary) is present in the package document, otherwise if false it means that the metadata is not present.

This means there is a positive indication in the accessiblity metadata within the EPUB confirming there are no sound hazards associated with this product.

unknown_if_contains_hazards

If true it indicates that the accessibilityHazard="unknown" (unknown hazards) is present in the package document, otherwise if false it means that the metadata is not present.

This means that the product has not been assessed for hazards and there is no information about potential hazards.

Variables setup

1. LET package_document be the result of calling preprocessing given package_document_as_text.
2. LET no_hazards_or_warnings_confirmed be the result of calling check for node on package_document, /package/metadata/meta[@property="schema:accessibilityHazard" and text()="none"].
3. LET flashing_hazard be the result of calling check for node on package_document, /package/metadata/meta[@property="schema:accessibilityHazard" and text()="flashing"].
4. LET no_flashing_hazards be the result of calling check for node on package_document, /package/metadata/meta[@property="schema:accessibilityHazard" and text()="noFlashingHazard"].
5. LET motion_simulation_hazard be the result of calling check for node on package_document, /package/metadata/meta[@property="schema:accessibilityHazard" and text()="motionSimulation"].
6. LET no_motion_hazards be the result of calling check for node on package_document, /package/metadata/meta[@property="schema:accessibilityHazard" and text()="noMotionSimulation"].
7. LET sound_hazard be the result of calling check for node on package_document, /package/metadata/meta[@property="schema:accessibilityHazard" and text()="sound"].
8. LET no_sound_hazards be the result of calling check for node on package_document, /package/metadata/meta[@property="schema:accessibilityHazard" and text()="noSoundHazard"].
9. LET unknown_if_contains_hazards be the result of calling check for node on package_document, /package/metadata/meta[@property="schema:accessibilityHazard" and text()="unknown"].

Instructions

1. Display "Hazards" as heading.

   This heading can be hidden if metadata is missing.

2. IF no_hazards_or_warnings_confirmed OR (no_flashing_hazards AND no_motion_hazards AND no_sound_hazards): THEN display "No hazards".
3. ELSE IF flashing_hazard OR motion_simulation_hazard OR sound_hazard: THEN LET hazards be an empty array.
   1. IF flashing_hazard: THEN APPEND "flashing" to hazards.
   2. IF motion_simulation_hazard: THEN APPEND "motion simulation" to hazards.
   3. IF sound_hazard: THEN APPEND "sound" to hazards.
   4. LET hazards_string be the result of:
      • calling join array to comma list given hazards
      • uppercasing the first character
      • concatenating " hazards" to the end of the string IF (length of hazards) > 1 ELSE concatenating " hazard" to the end of the string.
   5. display hazards_string.
4. ELSE IF unknown_if_contains_hazards: THEN display "The presence of hazards is unknown".
5. ELSE either omit this key informtion if metadata is missing or display "No information about possible hazards is available.".

Accessibility summary

This technique relates to Accessibility summary key information.

This algorithm takes the package_document_as_text argument: a UTF-8 string representing the Package document.

Being human-written, the accessibility summary will appear in the original language of the publication. Therefore it is necessary to take care of setting up the correct language tag information.

Accessibility summaries were necessary when no systems exposed computed accessibility metadata. With more systems now displaying this information, much of the accessibility summary may be redundant. Publishers should focus on adding information not provided within the computed metadata, such as specifying where in a video file a flashing hazard exists, or noting the reason why they failed to meet WCAG-AA due to color contrast issues in the Appendix.

Understanding the variables

accessibility_summary

If true it indicates that the accessibilitySummary is present in the package document, otherwise if false it means that the metadata is not present.

This means there is a human-written text containing a short explanatory summary of the accessibility of the product or the URL of a web page comprising such a summary. Summarizes the already existent information and may add information that the publisher could not express with the other codes.

lang_attribute_accessibility_summary

Returns the lang attribute of the node containing the accessibility_summary, or the lang attribute of the nearest anchestor.

This is the language code in which the text of the Accessibility summary was written.

language_of_text

Returns the value of nearest "language" (Language of content) if present in the package document, otherwise if false it means that the metadata is not present.

This indicates the main language of the content and therefore the most probable language of accessibility summary.

Variables setup

1. LET package_document be the result of calling preprocessing given package_document_as_text.
2. LET accessibility_summary be the result of calling check for node on package_document, /package/metadata/meta[@property="schema:accessibilitySummary"].
3. LET lang_attribute_accessibility_summary be the result of calling check for node on package_document, /package/metadata/meta[@property="schema:accessibilitySummary"]/(@lang|ancestor::*/@lang)[last()].
4. LET language_of_text be the result of calling check for node on package_document, /package/metadata/dc:language[1]/text().

Instructions

1. Display "Accessibility summary" as heading.

   This heading can be hidden if metadata is missing.

2. IF lang_attribute_accessibility_summary is NOT empty: THEN LET language_accessibility_summary be the value of lang_attribute_accessibility_summary.
3. ELSE LET language_accessibility_summary be the value of language_of_text.
4. ELSE IF accessibility_summary is NOT empty: THEN display the content of accessibility_summary with language_accessibility_summary as language.
5. ELSE either omit this key informtion if metadata is missing or display "No accessibility summary is available.".

Legal considerations

This technique relates to Legal considerations key information.

This algorithm takes the package_document_as_text argument: a UTF-8 string representing the Package document.

Understanding the variables

eaa_exemption_micro_enterprises

If true it indicates that the a11y:exemption="eaa-microenterprise" (EEA exception 1 – Micro-enterprises) is present in the package document, otherwise if false it means that the metadata is not present.

This means that the digital product falls under European Accessibility Act exemption for Micro-enterprises (as defined by current regulations). The product may not have to comply with requirements of the EAA if the publisher is a micro-enterprise.

eaa_exception_disproportionate_burden

If true it indicates that the a11y:exemption="eaa_disproportionate_burden" (EAA exception 2 – Disproportionate burden) is present in the package document, otherwise if false it means that the metadata is not present.

This means that the digital product falls under European Accessibility Act exception for Disproportionate burden (as defined by current regulations). The product may not have to comply with requirements of the EAA if doing so would financially overburden the publisher.

eaa_exception_fundamental_modification

If true it indicates that the a11y:exemption="eaa_fundamental_modification" (EAA exception 3 – Fundamental modification) is present in the package document, otherwise if false it means that the metadata is not present.

This means that the digital product falls under European Accessibility Act exception for Fundamental modification (as defined by current regulations). The product may not have to comply with requirements of the EAA if doing so requires a fundamental modification of the nature of the product or service.

Variables setup

1. LET package_document be the result of calling preprocessing given package_document_as_text.
2. LET eaa_exemption_micro_enterprises be the result of calling check for node on package_document, /package/metadata/meta[@property="a11y:exemption" and text()="eaa-microenterprise"].
3. LET eaa_exception_disproportionate_burden be the result of calling check for node on package_document, /package/metadata/meta[@property="a11y:exemption" and text()="eaa-disproportionate-burden"].
4. LET eaa_exception_fundamental_modification be the result of calling check for node on package_document, /package/metadata/meta[@property="a11y:exemption" and text()="eaa-fundamental-alteration"].

Instructions

1. Display "Legal considerations" as heading.

   This heading can be hidden if metadata is missing.

2. IF eaa_exemption_micro_enterprises OR eaa_exception_disproportionate_burden OR eaa_exception_fundamental_modification: THEN display "TBD".
3. ELSE either omit this key informtion if metadata is missing or display "No legal considerations".

Additional accessibility information

This technique relates to Additional accessibility information key information.

This algorithm takes the package_document_as_text argument: a UTF-8 string representing the Package document.