CSC requires all changes to Call & Authorized Lists at your central station to be submitted in writing with an authorized signature and date. You can request a CLVF from our office at any time by calling 781-321-9551, emailing us at monitoring@centralsignal.com, or via mail to Central Signal Corporation, 607 North Ave Bldg 18 Fl 2, Wakefield, MA 01880-1322 and make the changes directly on the CLVF.  You may also submit written changes without a CLVF via email or mail. Passcards will be mailed to you for any new authorized users you submit.