6000 Series—Medicine and Dentistry 7000 Series—Financial   Management 8000 Series—Ordnance   Material 9000  Series—Ships  Design  and  Material 10000  Series—General  Material 11000 Series—Facilities and Activities Ashore 12000  Series—Civilian  Personnel 13000  Series—Aeronautical   and   Astronautical Material These major groups are subdivided into primary, secondary, and sometimes tertiary breakdowns. The last three digits (the hundred group) of the code number designate   primary   subjects,   the   last   two   digits secondary  subjects,  and  the  final  digit  tertiary  subjects. For example, the 5000 series, General Administration and  Management,  could  be  further  broken  down  as follows: 5000 General Administration and Management 5 200 Management Programs and Techniques 52 10 Office Methods and Paperwork Management 521 1 Files and Records Systems Some  of  the  smaller  subject  groups  are  not subdivided below the primary breakdown. Other larger subject groups are divided into many secondary and tertiary subjects, the extent depending upon the scope and complexity of the major subject. SSICs are used to number and identify directives. For example, the first SECNAV-issued instruction on the files system is SECNAVINST 5211.1, and the subject  is  “Mail  and  File  Practices.”  Subsequent revisions  to  this  instruction  are  numbered  5211.1A, 5211.1B, and so forth When additional instructions on the subject of the files system are written, they are numbered 5211.2, 5211.3, and so forth. MISCELLANEOUS FILING PROCEDURES Most of the correspondence that you are required to file should have as SSIC. Even with an SSIC, you may have some difficulty deciding exactly where some correspondence should be filed because in some cases in may be filed under one or more SSICs. This is where your   experience   is   needed.   All   incoming correspondence should be screened and classified. Classifying Classifying, as the term is used here, is the process of determining the correct subject group or name title symbol under which correspondence should be filed and  subordinate  subjects,  if  any,  that  should  be cross-referenced. Classifying is the most important filing  operation  because  it  determines  where  papers should be filed. The proper way to classify a document is to read it carefully while you consider the following factors: The  most  important,  definite,  or  concrete  subject that is mentioned in the document The  purpose  or  general  significance  of  the document The manner in which similar documents are requested The subject identification code under which previous documents of a similar nature are filed The  SSIC  that  is  placed  on  the  letter  by  the originator may not be appropriate for every office; therefore, the text of the letters should be thoroughly screened and the letters filed correctly. Parts of a document (enclosures or attachments) should be filed with the basic document, if feasible. Cross-Reference Filing Although official letters usually are confined to one subject, they often may be properly classified under two or more file subjects; therefore, they may be filed under more than one file number. In such cases, a system of cross-referencing (indexing) is desirable. Cross-referencing  serves  a  useful  purpose  in locating material but should not be overdone. Not every document needs to be cross-referenced. It is a waste of time to list every cross-reference you can possibly think of. Try to select only those that will likely be of use. An endorsement should not be cross-referenced unless it contains subjects that are not covered by the basic correspondence. Charging  Out  Materials The  maintenance  officer,  division  officers,  or others  in  your  activity  use  the  correspondence maintained in your files. In many cases, they will only need to see the files on particular subjects and may not need  to  remove  the  files  from  the  maintenance administration office. On other occasions, they may 2-21