There are many kinds of media formats. The PSAP was designed to assess audiovisual formats most commonly found in American institutions. As comprehensive as the PSAP is, there may be many formats in your collections that don't fit into the format types we've listed in this resource. If you find you have a media type that the Collection ID Guide doesn't cover, there are resources to which you may turn to find out more about that media type's care. Following is a list of professional organizations and their email listservs. If you find you have a format that you can't identify, posting a message to these lists can usually put you in touch with a professional who can help you learn more about it.
Society of American Archivists (SAA)
Listserv subscription: http://www.archivists.org/listservs/
Additionally, you can visit sites like the Museum of Obsolete Media to help identify whatever problem or obscure format facing you.
Museum of Obsolete Media