The growing number of discarded computer systems has been accompanied by a similar trend in the number of discarded hard drives. A discarded hard drive however, is a unique form of waste because it carries large quantities of information that is closely related to its user. Consequently, the treatment of waste hard drives is an important issue in the context of data security, privacy, sustainable development and environmental conservation. With so many hard drive treatment options available, average computer users are often left clueless about which option is most suitable for their needs. This article will examine the currently available methods for hard disk destruction with a particular focus on their benefits, draw backs and suitability.
Degaussing – An overview
Degaussing is a procedure that involves the removal or elimination of an unwanted magnetic field. Since storage devices such as cassettes, hard disks and diskettes require magnetic fields to store data, degaussing is an effective way to erase data as it neutralises the magnetic fields present within the storage media. To comprehend how this process works, one must first understand how data is recorded onto hard drives, tapes and other magnetic media. Magnetic tape is composed of three major components: a tape recorder operates by moving the tape past a group of small metal blocks known as heads, at a constant speed. A tape recorder contains both playback and record heads. During recording, the record heads induce a magnetic field that repositions the coating of iron oxide into a digital recording pattern. The playback heads interpret this pattern and convert it into meaningful information. Hard drives work in the same way the only difference being that they are faster and more reliable. Instead of tape, a flat circular disk of metal, known as a platter is used. The platter is coated with a thin layer of chromium or iron oxide. The disc spins under a read/write head which magnetises the platter. A degausser will destroy this information by creating a magnetic field powerful enough to permanently nullify the magnetic properties of the chromium/iron -ore coating.
Consequences of Degausers:
Though degaussers are effective, they are often expensive and the performance of different models may vary according to the maximum strength of the magnetic field that can be achieved and on the coercivity of the storage media to be wiped. Shredding on the other hand is a highly effective and reliable method for hard drive destruction. A hard drive shredder will completely destroy the hard disk’s circuitry and its platter rendering it useless. Compared to degaussing, shredding is more reliable because it is not dependent on variable factors such as coercivity. It is also cheaper for individuals who routinely need to destroy their hard drives.