The New Zealand standard for data erasure (NZSIT 402) is used by many data destruction programs. It serves to overwrite existing information on a hard drive or other storage medium once and constitute, therefore, a software-based method for data erasure. The NZSIT 402 data erasure standard is the New Zealand government standard.
The NZSIT 402 data erasure process is generally implemented in the following manner:
Pass 1: Overwriting the data with a random character as well as verifying the writing of this character
By erasing a hard disk by means of the data erasure method NZSIT 402, the software-based restoration of data is generally prevented. A hardware-based data recovery also fails as a rule. The NZSIT 402 data erasure method was first published by the Communications Security Bureau in the Communications Technology Security Manual by the New Zealand government.