Priority, Immediate, and Flash. Figure 2-13 shows examples  of  the  different  types  of  precedence. complete  information  concerning  message  pre- cedence is contained in Naval Telecommunica- tions Procedures (NTP), Telecommunications Users  Manual,  NTP  3(H). Routine. —Routine is the precedence assigned to all   types   of   traffic   that   justify   electrical transmission but are not of sufficient urgency to require  a  higher  precedence.  The  Routine  pre- cedence is identified by the prosign  R. Priority.  —Priority  is  the  precedence  reserved for  messages  that  furnish  essential  information for the conduct of operations in progress. That is  the  highest  precedence  normally  authorized  for administrative  messages.  Priority  precedence  is identified by the prosign  P. Immediate.    —Immediate   precedence   is reserved for messages relating to situations that gravely  affect  the  national  forces  or  populace  and require  immediate  delivery  to  addressees.  Im- mediate  precedence  is  identified  by  the  prosign  O. Flash. —Flash  precedence  is  reserved  for  initial enemy contact reports or operational combat messages  of  extreme  urgency.  Message  brevity  is mandatory  in  Flash  messages.  Flash  precedence is identified by the prosign  Z. Another  precedence  is  the  Emergency  Com- mand. The Emergency Command precedence (ECP)  is  not  commonly  used  but  preempts  all other precedence. Its use is limited to the National Command  Authority,  certain  designated  com- manders of unified and specified commands, and specifically  designated  emergency  action  com- mand and control messages. When used, ECP is identified by the prosign Y. Messages  having  both  action  and  information addressees  may  be  assigned  a  single  precedence or a dual precedence. A dual precedence exists when a higher precedence is assigned to action addressees  than  to  information  addressees.  The assignment  of  a  dual  precedence  must  be  con- sidered on all messages with information ad- dressees  when  other  than  routine  precedence  is assigned  to  the  action  addressee(s). REACTION   TIME.   -The  precedence assigned to a message has no direct effect on the time by which a reply must be sent or on the precedence  assigned  to  that  reply.  Each  activity must  establish  its  own  requirements  concerning the  acknowledgment  of  messages.  The  following factors  should  be  considered  when  submitting  a reply  to  a  message: 1.  Does  the  message  have  a  reply  due  date? 2.   Must   the   reply   be   forwarded   by telecommunication  message,  or  can  it  be sent by naval letter or NAVGRAM? Regardless  of  the  reaction  times  established locally, Flash and Emergency Command pre- cedence messages requiring a reply must always be handled as quickly as possible. In some cases, you may be required to forward a reply to the originator  in  less  than  30  minutes. Date-Time  Group The date-time group (DTG) is assigned to messages  for  identification  purposes  only.  The DTG  consists  of  six  digits  followed  by  a  time-zone suffix (for example, 021930Z). The first pair of digits (02) denotes the day of the month; the second  pair  (19)  indicates  the  hour;  and  the  third pair (30), the minutes. All DTGs are expressed in  Greenwich  Mean  Time  (Z)  unless  otherwise directed by higher authority. In addition, the abbreviated month and year of origin are ap- pended  to  the  DTG.  Therefore,  the  DTG  021930Z JAN  91  would  be  identified  as  a  message  being officially released from a communications facility for transmission at 1930 hours, Greenwich Mean Time, on the 2nd of January 1991. Although  not  considered  as  part  of  the  date- time  group,  the  originator’s  name  must  be included  in  the  identification  of  a  specific message.  For  example,  NETPMSA  Pensacola  FL 032115Z  MAY  91  indicates  a  specific  message originated by Naval Education and Training Program  Management  Support  Activity,  Pensa- cola,  Florida.  However,  a  message  identified  only by the DTG 032115Z MAY 91 is not properly identified since any command in the Navy could have  released  a  message  with  the  same  DTG. Message  Format Figure 2-14 shows the Joint Message Form (DD-173/2).  Naval  Telecommunications  Pro- cedures  (NTP),  Telecommunications   Users Manual,   NTP  3(H),  and  U.S.   Navy   Plain Language  Directory,  NTP  3,  SUPP-1  (K),  give  the fundamental  format  and  procedures  for  preparing the naval message. ADDRESS COMPONENTS.  —The  address consists of the plain language address (PLA); the message  originator;  and  the  action,  information, 2-33