Recommended Formats Statement FAQ
How does the Library of Congress evaluate digital formats for the Recommended Formats Statement?
Digital file formats included in the Recommended Formats Statement (RFS) are evaluated by content teams comprised of Library of Congress staff with specific domain expertise. Each year, the content teams review entries in the RFS and document their findings on an evaluation matrix. A template of the matrix with sample data is available for download. The criteria in the matrix is updated as needed, for example accessibility support was added in 2024. A full list of all changes is shared in the Change Log available on the RFS home page.
What do "preferred" and "acceptable" formats mean in the context of the RFS?
The key underpinning to the RFS remains a focus on both global/community criteria and local/institutional criteria as key to preservation and long-term access. The global/community criteria have been based on the seven sustainability factors developed for the Library’s Sustainability of Digital Formats website: Disclosure, Adoption, Transparency, Self-documentation (including accessibility feature support), External dependencies, Impact of patents and Technical protection mechanisms. Each of these factors may have different emphasis or importance depending on the community of practice and content type. Some may not be applicable or essential for every format. The local/institutional factors estimate the level of resources at The Library of Congress available to preserve and manage the content over time. These include Staff experience and expertise, Software/Hardware/Operating System availability, Representation/extent in LC collections/storage, Established workflow/functionality and Access options including support on the Library’s website, loc.gov. The outcome of this analytical structure are clearer definitions of ‘Preferred’ and ‘Acceptable’ when categorizing digital file formats in the RFS.
Preferred formats:
- Global/community: Meets or exceeds benchmarks for all relevant sustainability factors
- Local/institutional: The Library of Congress has the skills, experience, workflows, tools and systems to manage and preserve these formats in current systems with confidence.
Acceptable formats:
- Global/community: Meets minimum acceptability across benchmarks or does not meet all relevant sustainability factors.
- Local/institutional: The Library of Congress can manage this format at a basic level of acquisition, management and preservation; and a greater ability for management and preservation is within the Library’s capacity with further investment.
The success in using this model opens the possibility of adapting it to apply to those other characteristics of creative works, both physical and digital, which the RFS covers in its remit to address all types of creative works.
What is the scope of the RFS?
Primarily, the RFS is geared towards published content as opposed to personal papers or archival acquisitions. The RFS is especially helpful for collections development plans and recommending officer who seek and acquire content so that they can be mindful of the Library's preferences and capabilities for specific file formats. If, for example, published content was available in more than one format, the recommendation would be to select the content in a preferred or acceptable format.
How does the RFS incorporate inclusive language?
Following the lead of the Federal Agencies Digital Guidelines Initiative (FADGI), it has been decided that the RFS will consider the term primary is an acceptable substitute for the term master and that the two convey the same intentions and meanings. Except for where master is part of a format's formal name (such as in IMF, Interoperable Master Format in Moving Image Works) or an industry standard use (such as gold master file for Software and Video Games), the RFS prefers the term primary.
For print material, such as textual works, series and musical scores, how is mass deacidified paper addressed?
The RFS is a guideline for publishers and manufacturers, and documents what materials and formats are preferred for the Library’s collections to facilitate preservation, but the Recommended Formats Statement does not document the Library’s entire preservation strategy. As book manufacturers and publishers do not use mass deacidified paper in the production of their materials, mass deacidified acidic material is not appropriate for the Recommended Formats Statement.
What is the review schedule for the RFS?
The RFS is updated yearly. Content teams first gather early in the year to discuss potential updates and changes. A public comment period is held for six to eight weeks in late winter, early spring. Comments then are adjudicated by the content teams and a new version is published in mid-summer.
Does the RFS cover all aspects of preserving and providing long-term access to creative content?
No. The Recommended Formats Statement is not intended to serve as an answer to all the questions raised in preserving and providing long-term access to creative content. It does not provide instructions for receiving material into repositories, managing that content or undertaking the many ongoing tasks which will be necessary to maintain this content so that it may be used well into the future. Tackling each of those aspects is a project in and of itself as each form of content has a unique set of facets and nuances. The RFS provides guidance on identifying sets of formats which are not drawn so narrowly as to discourage creators from working within them, but will instead encourage creators to use them to produce works in formats which will make preserving them and making them accessible simpler. The Library hopes that the RFS will help make it realistic to build, grow and save creative output for our individual and collective benefit for generations to come.
How to submit comments or questions
Comments and questions are always welcome, including outside the formal public review period. Send them to [email protected] or the appropriate content team lead.
