<Li> Enhanced overwriting involves three passes; each sector is overwritten first with 1s, then with 0s, and then with randomly generated 1s and 0s . </Li> <P> Regardless of which level is used, verification is needed to ensure that overwriting was successful . </P> <P> Apart from overwriting, other methods could be used, such as degaussing, or physical destruction of the media . With some inexpensive media, destruction and replacement may be cheaper than sanitisation followed by reuse . ATA Secure Erase is not approved . Different methods apply to different media, ranging from paper to CDs to mobile phones . </P> <P> The choice of method affects reusability . Four different outcomes are considered: </P>

Hmg ia standard no. 5 - secure sanitisation version 5.0 or later cesg