Magnetic tape that has contained classified information and is no longer useful should be destroyed. It is good practice to subject the tape to an approved degaussing procedure before releasing for destruction. The tape should then be removed from the reel and destroyed by incineration or disintegration. The reel should be divested of all labels or markings which indicate previous use or classification.Disks:
Disk packs or single disk platters that contain or have contained classified information and are no longer useful should be declassified and disposed of by the following methods of destruction, after labels have been removed:Core:
It is good practice to subject disk platters to an approved degaussing procedure before releasing for destruction.
- a. If available, make use of an approved metal destruction facility.
- b. Incineration.
- c. Apply an emery wheel or disk sander to the magnetic disk recording surface. Make certain that the entire surface is completely removed before disposal.
- d. Gamma ferric oxide disk surfaces can also be completely removed (i.e., chemically destroyed) by application of concentrated hydriodic acid (55% to 58% solution). Acid solutions should be used in a well-ventilated area only by qualified personnel.
Magnetic core memory which has contained classified information and is no longer useful should be declassified and disposed of by destruction. This should be accomplished by such methods as pulverizing, smelting, incinerating or by disintegration with a dry disintegrator such as the Security Engineering Disintegrator (model X22) with filter screen (3/32 inches) and sound enclosure.