Library Environment

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. 2-22