There is a common misconception that deleting files or reformatting a drive deletes data on a computer’s hard disk. This is not the case as data never truly goes away. Disposing of a computer’s hard disk drive therefore needs to be given special consideration.
Wipe the Hard Disk
Use software that will not only wipe your hard disk clean, but overwrite it with random patterns of data. This makes it hard to recover old data (such as confidential files). Eraser, one of the most popular free tools, allows you to set the number of “passes”, i.e. the number of times it overwrites all the data on the disk. The more passes you specify, the longer the procedure will take. Generally, one or two should be enough for most people’s needs, as those with criminal intent are more likely to move on to easier targets than spend time recovering masked data.
Use a Degausser
A degausser is a machine that can erase all information stored on hard disks, floppy disks, magnetic tapes or any other magnetic storage device in a quick and thorough manner. ITSC has a degausser SIMBO XBC-01. The Center’s usual practice is:
Computer server hard disks and tapes
1. Undertake a degauss with ITSC’s own degaussing unit.
2. Use a third-party disposal service to degauss and drill a hole on to the disks and tapes.
For hard disks and tapes too large for ITSC’s degaussing unit, the Center will acquire a third-party disposal service to degauss and drill hole on to the disks and tapes.
End user computer hard disks
1. Undertake a degauss with ITSC’s degaussing unit.
2. Mark the disks as degaussed and dispose as scrap metal.
Departmental Technical Support Staff should contact ITSC to use the in-house degaussing unit or obtain more information. For third-party services, contact the Purchasing Office for details.