What is Data Sanitization?

Data sanitization is the umbrella term for all methods used to ensure that data stored on electronic media cannot be recovered by any known technique. Unlike simple file deletion — which only removes the file system pointer — sanitization renders the actual data unreadable.

There are several sanitization methods, each appropriate for different situations. Software-based overwriting (data wiping) writes patterns over the entire storage surface multiple times. Cryptographic erasure destroys the encryption keys that protect self-encrypting drives. Degaussing uses powerful magnetic fields to erase magnetic media. Physical destruction (shredding, crushing, or disintegration) renders the media physically unusable.

The choice of sanitization method depends on the sensitivity of the data, the type of storage media, and whether the device will be reused or recycled. NIST 800-88 provides a decision framework for selecting the appropriate method. Regardless of method, proper data sanitization always includes verification and documentation.