the data your command processes (Unclassified,
Confidential, Secret, Top Secret), you must ensure that
the library is secure.
Another security requirement is fire control. Smoke
and fire alarm systems are necessary. Sprinkler systems
that react immediately to any threat of fire area must.
Insulated vaults (safes) and storage cabinets like the
ones shown in figure 2-13 are extremely helpful in
preventing magnetic media and paper records from
being destroyed in the early moments of a fire before it
can be put out. They can also help reduce the heat to
which the storage media are exposed. Heat can be
particularly harmful and damage the data even if the
medium itself is not destroyed, because plastic melts,
and metal warps.
If the storage devices are insulated, this will further
protect against water damage, either from natural
accidents, such as floods, the sprinkler system, or
personnel putting out a fire. Some commands prefer to
use an inert-gas extinguishing system, or chemical fire
extinguishers rather than the conventional water
sprinklers. These help to eliminate the damage and
contamination that would otherwise be caused by water.
Another safety feature is the lead-strip vault door hinge.
The lead strip will melt at 150°F and automatically close
the vault door (see figure 2-14).
LIBRARY ENVIRONMENT
The library is usually located in the same
functional area as the computer room it is supporting.
This is especially true aboard ship. Magnetic tape,
disk, and other media must be maintained within the
same environment, or the same type environment, as the
Figure 2-13.—Media storage vault and cabinet
(with doors open).
Figure 2-14.—A lead strip bolted in the vault
door hinge.
computer facility. If not, the media should be placed in
the proper environment for a minimum of 24 hours
before using; otherwise, the operators may encounter
problems using the media. Temperature and relative
humidity tolerances should be maintained within
specified limits. In the absence of other instructions,
maintaining a 30 to 60 percent relative humidity at 70°F
to 80°F is considered an acceptable environment.
In the library, especially the tape cleaning area, the
elimination of dust, lint, and foreign matter on
equipment is necessary for efficient operation. In short,
the cleanliness of equipment, floors, and contact areas
and the control of humidity and temperature are
essential.
Traffic in and out of the library should be kept to a
minimum. Smoking, eating, and drinking should be
prohibited at all times.
The library should be vacuumed and/or cleaned
with a damp mop. A dry mop, fox tail, or dust broom
should never be used, as they tend to kick up more dust
than they take up. Aerosols should never be used in the
library environment, because the oily, dust-collecting
moisture settles and eventually finds its way onto the
equipment as well as the surfaces of the media.
The use of air-conditioning filters in the library
should be given special attention, because fiber glass
filters often fail to prevent the penetration of fine silts
and tend to deposit particles of fiberglass on magnetic
media.
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