VMS Help SET, VOLUME, Qualifiers, /FILE_PROTECTION  *Conan The Librarian (sorry for the slow response - running on an old VAX)

       /FILE_PROTECTION=(ownership[:access][,...])

    Sets the default protection to be applied to all files on the
    specified disk volume. Specify the ownership parameter as system
    (S), owner (O), group (G), or world (W) and the access parameter
    as read (R), write (W), execute (E), or delete (D). A null access
    specification means no access.

                                   NOTE

       This attribute is not used while the volume is in use on an
       OpenVMS system, but the attribute is provided to control
       the process use of the volume on RSX-11M systems. The
       OpenVMS system always uses the default file protection;
       the protection can be changed with the DCL command SET
       PROTECTION/DEFAULT.