The combination of a security container used for
the storage of classified material is assigned a security
classification equal to the highest category of classified
material authorized to be stored in the container.
Records of combinations are sealed in an envelope
(Standard Form 700) and kept on file in a central
location designated by the commanding officer.
Cipher locks and safe combinations are handled in
accordance with guidelines found in the Security
Manual. With the addition of electrically actuated
locks (that is, cipher and magnetic strip card locks), this
type of lock still does not afford the degree of protection
required for classified information. They may NOT be
used as the primary means to safeguard classified
material. Cipher or magnetic strip card locks are
normally used for access to an area only.
Classified documents and material must be clearly
and conspicuously marked. Special markings, such as
LIMDIS and Restricted Data, are normally placed near
the classification markings. These markings inform
and warn recipients of the classification assigned and
indicate the level of protection required. These
markings also identify the information that must be
withheld from unauthorized persons.
Top Secret, Secret, and Confidential classification
markings must be stamped, printed, or written in capital
letters larger than those used in the text of the document.
These security markings should be red in color, when
practicable, and be placed at the top and bottom center
of each page.
All reproductions or copies of classified materials,
regardless of form, must bear clearly legible security
classification markings and notations in the same
manner as on the copied or reproduced material.
Copying equipment does not always clearly reproduce
all colors of ink or marginal images. If the reproduction
process does not clearly reproduce the security
markings appearing on the original copy, all copies
must be marked in the same positions and size as on the
Paragraph markings are required for classified
documents. The appropriate security markings are
placed at the beginning of the classified paragraph. The
symbols used to indicate paragraph classification are
(TS) for Top Secret,(S) for Secret, (C)for Confidential,
and (U) for Unclassified.
It is not uncommon to see foreign-originated
classified information in U.S. messages and documents.
Paragraphs that contain foreign-originated classified
information must be properly marked; for example,
U.K.(C) or NATO(S).
At the beginning of Restricted Data and Formerly
Restricted Data paragraphs, use the appropriate
classification symbol with the abbreviation RD or
FRD, such as (S-RD), (C-FRD).
Titles and subjects are classified according to their
content, regardless of the overall classification of the
document. Normally, the symbols indicating the
classification assigned to a title or subject are placed in
parentheses immediately following the item, as in the
In addition to security classification categories,
other markings also appear on some documents and
messages. Among these markings are such
designations as Restricted Data (RD), Formerly
Restricted Data (FRD), LIMDIS, FOUO, EFTO,
SPECAT, PERSONAL FOR, NATO RESTRICTED,
and ALLIED RESTRICTED.
Restricted Data and Formerly Restricted Data
The marking Restricted Data (RD) is applied to
all data concerned with the design, manufacture, or use
of nuclear weapons. Also included in this category is
the special nuclear material used in energy production.
The marking Formerly Restricted Data (FRD)
pertains to defense information that has been removed
from the RD category but must still be safeguarded as
classified defense information. FRD material cannot be
released to foreign nationals except under specific
LIMDIS (Limited Distribution)
The LIMDIS designator is applied only to classified
messages which, because of the subject matter, require
limited distribution within the addressed activity.