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Disposal of old computers

University policy for computer disposal

The University policy for disposal of equipment that is surplus to the requirements of the unit that originally purchased is that reasonable efforts should be made to see if any other unit is able to make use of the equipment.

Equipment that has residual value may be sold, either to University members or outside bodies, subject to the University's financial guidelines.

Where equipment has limited resale value, consideration should be given to whether it can be donated to any charitable or community project. If the equipment cannot be reused, then it should be recycled or disposed of in an environmentally-friendly manner.

Importance of data removal

An overriding consideration in any move of equipment must be to ensure that any University data on the machine, and any software licensed to the University, is removed. It is, of course, vital to satisfy the requirements of the Data Protection Act, but it must also be understood that any University data that is discovered by a later owner may cause controversy, adverse publicity, etc.

Ensuring adequate destruction of data is the responsibility of the unit that owns the equipment, and must not be delegated to any person outside the University without adequate contractual obligations being imposed.

Means of disposal

The following mechanisms have been put in place.

Where machines are to be given to charities, schools, etc., then it is necessary that someone (ie someone within the University) who is interested in the particular good cause should volunteer to take charge of the process, and act as the University's agent in ensuring that the proper steps are taken. If a department is handling this privately, eg giving a few machines to a school or selling one to a member of staff, then basically the same procedures should be followed.

Computer monitors are defined as hazardous waste, and arrangements for their disposal must be handled through the University Safety Office.

Other computer equipment that has no further use should be disposed of by an authorised contractor, who will guarantee that all data is destroyed, and that equipment will be properly recycled or disposed of. The University Safety Office provides details of the procedures that must be followed. Please see:

Questions on policy should be referred to the University Data Protection Officer or the University Safety Office, as appropriate. To learn more about the University re-use scheme please contact the Environmental Sustainability team on

Deleting data: technical aspects

Before disposing of any computer system, it is vital to remove all traces of data files. Merely deleting the visible files is not sufficient to achieve this, since data recovery software could be used by a new owner to 'undelete' such files. The disk-space previously used by deleted files needs to be overwritten with new, meaningless data - either some fixed pattern (eg binary zeroes) or random data. Similarly, reformatting the whole hard disk may not in itself prevent the recovery of old data as it is possible for disks to be 'unformatted'.

The most well-known tool for fully wiping old data files is the 'Wipe Info' module of the Norton Utilities suite for PC and Macintosh systems. This will completely wipe the contents of any specified files, or the whole of the free space on the disk. However, this approach still assumes that you have located every file that needs to be taken care of, which may not always be easy.

A better approach is to reformat the hard disk, installing a clean copy of the original operating system, and then run Wipe Info on the free space. This should leave a machine in a suitable state for disposal.

Older versions of Norton Utilities included a utility called 'WipeDisk' which could fully wipe the entire hard disk on a PC booted-up from a floppy disk. Other utilities of this type are available.

Virtually every PC is bought with a licence for the operating system supplied with it. A machine can therefore be legitimately disposed of with a freshly installed copy of the same system. However, you should not install a later copy of the system software.