The new Available on shelf facet allows patrons and staff to limit to items that are currently available in the library. The facet uses the item's Current Library and excludes items that are checked out, in transit, or waiting on the hold shelf, as well as items with one of the Not for loan, Lost, or Damaged statuses. Accordingly, if your library owns two items that appear in a list of search results, but one of those items is checked out, only the item that is not checked out will appear in the Available on shelf facet.
To generate a list of items owned by a particular library, regardless of status, use the Advanced Search and choose a library from the Location and availability drop-down list. To limit the search to only items available on shelf click the Only items currently available for loan or reference checkbox.