The American Department of Defense standard for data erasure (DoD 5220.22-M) is used by several well-known programs for secure data erasure. It converts a 3-fold overwriting of the data.
The DoD 5220.22-M data erasure procedure is carried out as follows:
Pass 1: Overwriting the data with a zero as well as checking the writing of this character;
Pass 2: Overwriting the data with a one and checking the writing of this character;
Pass 3: Overwriting the data with a random character as well as verifying the writing of this character.
The method of extinguishing the DoD 5220.22-M is considered secure. A software or hardware-based restoration of data that has been erased with the DoD standard is generally excluded. The DoD 5220.22-M deletion standard was published by the US National Industrial Security Program (NISP).