How to create PDF/A files for long-term archiving

PDFs are the gold standard file format for most businesses when it comes to digital documents. They are versatile, easy to use, and viewable on any device without worrying about formatting issues. But here’s the catch, not all PDF formats are the same, and some are better for long term document storage and preservation. That’s where PDF/A comes in.

PDF/A is a type of PDF designed specifically for long-term digital archiving and preservation of electronic documents. As technology evolves, digital files are increasingly replacing paper documents. This makes it crucial to have a method that ensures easy retrieval and display of documents over an extended period.

In Europe, various organizations and governments recommend or even legislate PDF/A for long-term archiving. In the U.S., recommendations exist in the fields of jurisdiction and libraries. The main goal of this format is to limit and define technologies. This helps ensure that the files display accurately in the distant future, even when users use different software. 

PDF/A compliance requires files to meet certain ISO requirements. Everything needed to accurately render the document must be contained within the file, including fonts, color profiles, images, and other elements. This ensures that any PDF viewer, now or in the future, has everything it needs to display the document correctly. While PDF files can be converted to PDF/A format, not all features of the source PDF may be transferable, nor can the converted files be encrypted. 

At first glance, these two formats are the same. The standard file is designed for sharing, editing, or forms. Meanwhile, the other format is made specifically for archiving. It locks in content, removes active elements, and ensures it stays the same over time. One is flexible; the other is built to last.

The PDF/A format exists in different variants. Each of them has different standards and conformance levels. Each standard defines the features and image compression technologies, which help to preserve the content of a file.

Moreover, the PDF/A standard supports a variety of conformance levels. Through these levels, the accessibility requirements that impact the understanding of the content are being controlled. By knowing the different options for PDF/A, you can improve the value of your documents for your viewing, printing, sharing and archiving purposes.  

• PDF/A-1 is the original PDF/A standard and comes with some restrictions regarding the use of fonts, color, annotations and some other elements. It comes in level b (basic) and level a (accessible):
• PDF/A-1b focuses on the preservation of the visual appearance of a document.
• PDF/A-1a adds features that improve the file's accessibility for physically impaired users. Its requirements include reliable text semantics and structure information to preserve the document’s natural reading order and logical structure.
• PDF/A-2: This standard has several additions, such as JPEG 2000 compression and optional content layers as well as PDF packages. It also allows file attachments, if the attached documents themselves adhere to PDF/A-1 or PDF/A-2 standards. While PDF/A-2 also comes with level b and level a conformance, a new conformance - level u (unicode) was introduced. It guarantees that the text can be reliably searched and copied.
• PDF/A-3 is almost identical to PDF/A-2. The only difference is that it allows arbitrary file formats to be embedded into PDF/A conforming files. These arbitrary file formats are CSV, CAD, XML, spreadsheet documents, word-processing documents, and more. Additionally, this is the standard that can be used with ZUGFeRD.

Now that you are more aware of what the different PDF compliance formats are and how the PDF/A standard is used. We would like to share some use cases for long-term document storage for various industries.

Now that you are more aware of what the different PDF compliance formats are and how the PDF/A standard is used. We would like to share some use cases for long-term document storage for various industries.

Governments around the world require official records, permits, and historical documents to be stored in a secure manner for permanent access. It ensures documents can still be opened and trusted far into the future, even if software changes.

Banks, insurers, and auditors use this format to secure financial statements, audit trails, and transaction histories. The format guarantees long-term accessibility and data integrity, both of which are essential for audits and regulatory reviews.

The healthcare industry has sensitive data such as patient histories and consent forms. These often need to be preserved securely for many years. With long-term archiving it ensures these documents remain readable and protected, aligning with health data regulations like HIPAA.

HR files, internal policies, contracts, employee agreements, and board meeting minutes are often archived for internal use and compliance. It is useful for any PDF document which may be needed in the future and requires a tamper-proof, self-contained solution that stands up to audits and internal reviews.