Why PDF/A?
The feature-rich nature of PDF can create difficulties in preserving information over the
long-term, and some useful features of the PDF file format are incompatible with the
demands of long-term preservation. For example, PDF documents are not necessarily
self-contained, drawing on system fonts and other content stored external to the original
file. As time passes, and especially as technology changes, these external connections can
be broken, and the dependencies cause information to be lost. Additionally, because of
the lack of standardization among the many PDF development tools on the market, there
is inconsistency in the implementation of the file format. This lack of standardization
could be chaotic for the information managers of the future, especially as
it would be difficult (if not impossible) for them to “get under the hood” of the PDF files
unless a format specification were put in place that specifically addressed long-term
preservation needs.
What is PDF/A?
ISO 19005-1, Document management — Electronic document file format for long-term
preservation — Part 1: Use of PDF 1.4 (PDF/A-1) is the first in a new family of ISO
Standards to address the growing need to maintain information in electronic documents
over archival time spans.
Because this initial version of PDF/A is based on PDF 1.4, the standard is being
published in parts so that new parts can be added without obsolescing previous parts. For
example: PDF/A-1 refers to the format defined by Part 1 (ISO 19005-1) of the standard
(or PDF 1.4) while Part 2 (ISO 19005-2) and later parts may be based on a later version
of PDF and/or may define archiving requirements for more complex content types.
