A restricted retention period has been established to prevent permanent physical damage to magnetic tapes, especially tapes that are stored for long periods of time, such as history tapes. This provides for all magnetic tapes to be cleaned, possibly certified, and repacked at prescribed time intervals. This procedure eliminates such problems as oxide sticking, debris embedment, and edge deformation caused by tape pack shifts inside the reel. Initially, an on-site save tape retention period should be restricted to a maximum of 90 days, with only one 90-day extension. After 180 days, you should notify the user indicating that the tape should be copied (and verified) onto a recently cleaned tape, thus freeing the original tape to be tested for accuracy. The retention period for off-site tapes should initially be 180 days, with one 30-day extension.
