VMS Help SET, BROADCAST, Examples  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    1.$ SET BROADCAST=(NOMAIL, NOPHONE)
         .
         .
         .
      $ SET BROADCAST=MAIL

      In this example, the first SET BROADCAST command screens out
      all mail and phone messages. Later the second SET BROADCAST
      command restores mail messages. Phone messages are still
      screened.

    2.$ SET BROADCAST=NONE
         .
         .
         .
      $ SET BROADCAST=(SHUTDOWN, URGENT, DCL, OPCOM)

      In this example, the first SET BROADCAST command screens out
      all messages. Later the second SET BROADCAST command restores
      shutdown, urgent, DCL, and OPCOM messages. General, phone,
      mail, queue, and user messages are still screened.