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Web Standard: Standard Web Formats and Proprietary File Formats


The EPA standard formats for publishing information on the Web are HTML and PDF. Many programs create file formats with unique file extensions (e.g.; .doc, .pptx, .zip). Proprietary formats (e.g.;  .docx, .xls, .ppt, .exe) should be used only when necessary e.g., when providing forms or other documents that users may need to edit or files for installing software. These files are rarely updated and are more likely to become redundant, outdated or trivial. Consider carefully before publishing these types of files.

Content Requirements

  • Scan files for viruses before loading.
  • When linking to other file formats, follow this format: <link>Document Title (DOCX)</link> 
  • ​Video and audio files should include run time. Examples:
    • Podcast Title (MP3) (03:35, 256K)
    • Video Title (WMV) (02:25, 3.4MB)
  • You may only use file types for applications which EPA has a Terms of Service agreement. Terms of Service are negotiated at the Agency or federal level.

About this Standard

All EPA public web content must adhere to the EPA Web Standards, the U.S. Web Design System guidelines, and the 21st Century Integrated Digital Experience Act.

Original effective date: 09/12/2012
Last approved on: 08/12/2020
Web Council review by: 08/12/2023 (or earlier if deemed necessary by the Web Council)