DECLARE
        bBlobContent  blob;
        sFileName       varchar2(100) := "Файл";
        sMime            varchar2(100) := 'text/csv';
        sLength          varchar2(20);
BEGIN
 
        SELECT bload_std    ,  TO_CHAR(dbms_lob.getlength(some_blob))
        INTO   blob_content ,  sLength
        FROM   some_table
        WHERE  some_id = :another_id   ;

        OWA_UTIL.mime_header (NVL (sMime, 'application/octet'), FALSE);
        HTP.p ('Content-length: ' || sLength);

        if INSTR(UPPER(OWA_UTIL.GET_CGI_ENV('HTTP_USER_AGENT')), 'MSIE') > 0 then
           HTP.P ('Content-Disposition:  attachment; filename="' 
           || UTL_URL.ESCAPE( sFileName, FALSE, 'UTF-8' ) || '"');
        else
           HTP.P('Content-Disposition:  attachment; filename*=UTF-8'''''||UTL_URL.ESCAPE( sFileName, FALSE, 'UTF-8' ));
        end if;

        OWA_UTIL.http_header_close;
        WPG_DOCLOAD.download_file(blob_content); 
END;