Resource directory for the Z39.98-2012 Authoring and Interchange
DIAGRAM Description Profile
version 1.0

Table of Contents


The DIAGRAM Description Profile is intended to serve as a format for authoring accessible descriptions to accompany images and graphics.

The contents of this data model were developed under a grant from the US Department of Education, #H327B100001, under the direction of the DIAGRAM Center. However, those contents do not necessarily represent the policy of the US Department of Education, and you should not assume endorsement by the Federal Government. Project Officer, Glinda Hill.

Normative References

The keywords "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this section are to be interpreted as described in RFC2119.

Version information

This resource directory represents version 1.0 of the DIAGRAM Description profile:

This release may not be the most recently published (current) version of the DIAGRAM Description profile. The current version should always be obtained from the static URI:


This profile must be identified as descriptions in Z39.98-AI document profile declarations.

The canonical identity URI is:

Specification compliance

This version of the profile is compliant with the Z39.98-2012 Specification.

Normative schemata

The normative RelaxNG schema for version 1.0 of the DIAGRAM Description profile is z3998-descriptions.rng.

Note - this schema includes embedded ISO Schematron assertions. A standalone ISO Schematron schema is provided for use in authoring tools that do not support embedded ISO Schematron.

The normative schema includes a number of modules and/or subschemas, which are listed in Appendix 1.

Supported features

The DIAGRAM Description profile supports the following features:

RDFa initial context

The URI of the initial context document is:

Refer to the context document at this location for additional information about the default vocabulary and pre-defined vocabulary prefixes.

Informative References

Schema documentation

Schema documentation is available online, and is also included in the downloadable archives.

Tutorials and Primers

Refer to the Z39.98-AI community portal for additional information on how to use this profile .

Document templates

A document template is available for use as a starting point when creating documents conforming to this profile.

Refer to Editor setup and configuration for information on how to use this template in an XML editor.

Sample documents

Sample documents conforming to this profile are available from the Z39.98-AI Working Group's source code repository.

Informative schemata

The following informative schemata are available:

An ISO Schematron schema that contains the Schematron rules extracted from the normative RelaxNG schema.
An experimental NVDL script that combines the RelaxNG and Schematron validation into a single step is also available. Tool support for this script is currently limited.

Feature-reduced schemata

These schemata are variants of the normative RelaxNG schema that have one or several features removed. They are provided for convenience during the authoring stage.

An instance document valid to a feature-reduced schema will also be valid to the normative schema.

Cascading Stylesheet (CSS)

A default CSS stylesheet is available for use with CSS-aware XML Editing applications.

Refer to for instructions on how to associate a CSS stylesheet with a document instance.


The schemas, documentation and resources referenced in this directory are available for download in the following formats:

Supporting software

Refer to the Z39.98-AI community portal for information on available software tools.

Appendix 1: Listing of modules in the normative schema

The below list represents the modules at the time of version 1.0 of this profile.

The occurrence of the keywords "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in documentation fields embedded in these modules are to be interpreted as described in RFC2119.