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Web Standard: Audio files Use MP3


  • Audio files play sound.  There are no images.
  • Max file size limit is 1000MB.

Content Requirements:

  • Audio files are MP3.
  • Will need a transcript for the information in the MP3 to meet 508 requirements.
  • Audio files should be technology agnostic and played by the browser.  This means you should not use proprietary products such as AIFF or WAV.
  • You may only use file types for applications which EPA has Terms of Service agreements.  Individuals may not accept most standard on-line terms of service agreements. Terms of Service is negotiated at the Agency or federal level.


Public Service Announcements

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: 04/08/2015
Last approved on: 03/11/2020
Web Council review by: 03/11/2023 (or earlier if deemed necessary by the Web Council)