Preservation Recording, Copying, and Storage Guidelines for Audio Tape Collections
Source: Lyrisis – Preservation Services Leaflet
Magnetic media (audiocassettes, audiotape, videotape, computer disks, etc.) are inherently unstable, with an approximate shelf life of 25 years. This does not mean that every tape will selfdestruct in 25 years, but rather that the signs of deterioration begin to appear by this time.