A  notice  usually  remains  in  effect  for  less  than  6 months, but is not permitted to remain in effect for longer than a year. A notice has a self-canceling provi- sion. The cancellation date is always stated. When the exact length of time a notice is to remain in effect cannot be determined at the time of issuance, the specific date for record purposes is set far enough in the future to allow  all  necessary  uses  of  the  notice.  Reports  and procedures covered in a notice are considered canceled when the notice is canceled, unless requirements have been  issued  in  another  document.  Cancellation  determi- nations are shown at the top right comer and/or as a last paragraph  titled  Cancellation  Contingency. Change  Transmittal A change transmittal is the medium used to transmit changes to an instruction, and under special circum- stances, to a notice. Each transmittal describes the na- ture of the change it transmits and gives directions for making the change. Drafting  Instructions  and  Notices When drafting instructions and notices use the same rules and procedures that you would if you were draft- ing any type of correspondence. Instructions and no- tices must be clear, concise, and easily understood. Clarity of language as well as neatness in appearance of the instruction or notice will promote increased under- standing by recipients and greater efficiency within your   organization. The elements of a directive, both as to content and format, generally in the order that they appear in a directive, are contained in table 1, Preparation of Let- ter-Type Directives, and table 2, Preparation of Special- Type  Directives,  of  SECNAVINST5215.1C.  The  Navy Correspondence  Manual,   SECNAVINST    5216.5C, provides  additional  guidance  on  the  preparation  of  di- rectives. FILING  DIRECTIVES Instructions  normally  should  be  filed  according  to (1) subject identification number, (2) consecutive num- ber,  and  (3)  issuing  authority,  Checklists  of  directives issued  by  Washington  headquarters  organizations should be organized in this manner. If local conditions require,  however,  directives  may  be  filed  primarily  by issuing authority or by a combination of subject identi- fication  number  and  issuing  authority.  You  should action,  you  may  file  them  on  your  office’s  general subject  files,  pertinent  case  files,  or  other  appropriate correspondence   files. FILES As an LN, you must be able to file correspondence correctly and retrieve it quickly. The amount of time it takes you to locate a certain piece of correspondence depends on how well you know the Navy’s filing sys- tem. This section introduces you to the Navy way of filing. You are introduced to various procedures that will help you to perform your duties efficiently. You are also instructed in using the numerical subject identifi- cation coding system that was addressed previously and contained in the  Department  of  the  Navy  Standard Subject Identification Codes (SSIC),  SECNAVINST 5210.11D. The SSIC contains the numerical codes that provide the basic classification structure for identifying and filing records. These codes cover most subjects found in  general  correspondence  and  other  files.  Since  these numbers are used for numbering other naval documents such as reports, forms, and directives by subject cate- gory, they also provide the basis for a single Navywidc subject numbering system. 1-7 disregard alphabetic prefixes (C and S showing security classification)  to  the  subject  designation  in  determining the numerical filing sequence. Because of their brief duration, you need not file notices in the master file. If it is necessary to interfile them with instructions temporarily, the notices should be tabbed so each may be easily and promptly removed as soon as its cancellation date is reached. Copies may be  filed  in  separate  binders  when  necessary. File  cross-reference  sheets  for  instructions  perma- nently or temporarily removed from your office with these  instructions.  Insert  locator  sheets  in  normal  se- quence in place of the removed instructions they refer- ence.  You  should  place  a  subject  cross-reference  sheet in front of those instructions that carry the same subject identification  number.  A  second  copy  of  the  cross-ref- erence sheet should be placed in a suspense file for temporarily loaned instructions. An instruction should be returned within 5 days, unless the borrower is still using it. When you need copies of directives to complete a record or to support or further document a specific