Understanding PDF Standards – PDF/A

With its release as an open standard in 2008, the PDF format received a special treatment. Now, it is owned by the International Organization for Standardization (ISO). Thus, the PDF format has to follow certain standards that ensure that everyone can open and view PDF files.

In addition to the ISO standard, three different subsets of standards for PDFs were created and every PDF must adhere to one of these standards. Today, we’ll have a look at one of them: PDF/A 

The PDF/A Standard

This standard was established for PDFs that serve the purpose of long-term archiving.

For PDFs that should be preserved over a very long period of time, this standard should be used. It ensures that PDF documents of this standard can still be opened and read in the future when PDF technology has developed further.

This might also interest you: All about the PDF 2.0 Standard

In order to comply with this standard, the documents mustn’t contain any external media or content such as images, fonts, audio or video files, encryption, javascript, among others. This means that a PDF document using this standard is self-contained to 100%.

For a full list of external sources prohibited in PDF/A files, check out the wiki page.

Proper PDF/A viewers also have to adhere to these standards.

Problems With PDF/A

While PDF/A standardized PDF documents might be perfect for archiving, they also come with a few disadvantages:

  • large file size due to embedded fonts and images
  • in earlier versions, transparency was removed from the PDF and embedded images
  • conversion from “normal” PDFs to PDF/A can contain faulty glyphs, especially when using OCR

When To Use PDF/A

There are some purposes and common reasons why mainly businesses use or should use PDFs saved in this standard. Below is a short, by no means complete, list.

  • archiving scanned legal documents
  • migrating archives
  • storing important office or business documents
  • turning database entries into documents
  • collaborating with a team