The Secure Erase data sanitization method is implemented in the following way:
- Pass 1: Writes a binary one or zero
No verification is needed because the writing occurs from within the drive, meaning the drive's write fault detection prevents any misses. This makes Secure Erase very fast compared to other data sanitization methods.
Once a hard drive has been erased with a program that utilizes Secure Erase firmware commands, no file recovery program, partition recovery program, or other data recovery method will be able to extract data from the drive.
Some specific Secure Erase commands include SECURITY ERASE PREPARE and SECURITY ERASE UNIT.
Several free hard drive erasing programs work via the Secure Erase command. See this list of Free Data Destruction Software Programs for more information.
Using Secure Erase to erase the data from a hard drive is often considered the best way to do so because the action is accomplished from the drive itself, the same hardware that wrote the data in the first place. Other methods of removing data from a hard drive may be less effective because they rely on more standard ways of overwriting data.
According to National Institute of Standards and Technology Special Publication 800-88 [PDF], the only method of software-based data sanitation must be one that utilizes a hard drive's Secure Erase commands.
It's also worthwhile to note that the National Security Administration worked with the Center for Magnetic Recording Research (CMMR) at the University of California, San Diego, to research hard drive data sanitation. A result of that research was HDDErase, a freely available data destruction software program that works by executing the Secure Erase commands.
Secure Erase is not available on SCSI hard drives.
Note: You can not run firmware commands on a hard drive like you can run commands in Windows from the Command Prompt. To execute Secure Erase commands, you must use some program that interfaces directly with the hard drive and even then, you probably won't be running the command manually.
Important: Some programs exist that have the words secure erase in their names or advertise that they securely erase data from a hard drive, but unless they specifically note that they use a hard drive's Secure Erase commands, they likely do not.