The PREL website has been designed to be highly accessible to persons
visiting our site through the use of assistive technologies. Visitors
who need to make use of these features may include:
with visual impairments who use text-to-speech converters (programs
which convert webpages directly to text)
People with hearing impairments who may need phonetic equivalents
for audio materials
with impaired mobility who have difficulty using a conventional mouse
The following provides information for
visitors to help make the most of these accessibility features.
Images are provided with text equivalents which describe the content of
the image. Images without visual content (e.g., an image which supports
page layout) are provided with zero-length text equivalents.
This site contains content in Adobe Acrobat format, also known as “Portable
Document Format” or PDF. There is currently no available direct
text-to-speech converter for Acrobat documents, as Adobe is currently
developing this software.
However, this site does provide a link to a text-only version of each
Acrobat document. The accessible link is always adjacent to the link which
references the original PDF document. The text-only version is provided
by executing a service on the Adobe website. This service then retrieves
the document from the PREL website, converts it to HTML and displays the
For persons who are not using a speech-to-text
converter, the Acrobat reader may be downloaded from the Adobe website
Portions of this website were developed under federally funded programs.
The site has been designed to comply with federal standards for website
accessibility as defined in Section 508 of the Rehabilitation Act of 1973.
The pages on this site have been tested
for compliance against guidelines adopted by the World Wide Web Consortium
(also known as the W3C). The site complies with all Priority 1 checkpoints
as defined in the Web Content Accessibility Guidelines 1.0 W3C Recommendation
Cascading Style Sheets conform to W3C Specifications for Cascading Style
Sheets. The site is also fully accessible without the application of its
style sheets. The site conforms to requirements for Bobby Approval per
the guidelines of the Center for Applied Special Technology (CAST).
Federal Access Board - Accessibility Guidelines and Standards [www.access-board.gov/gs.htm]
World Wide Web Consortium - Accessibility Initiative [www.w3.org/wai/]
National Institute on Disability and Rehabilitation Research [www.ed.gov/about/offices/list/osers/nidrr/index.html]
Information on Alternative Web Browsers [www.w3.org/WAI/References/Browsing]