University of Vermont

Information Technology

Disposal of Surplus Computers and Electronic Waste
Frequently Asked Questions

  1. Why do I need to do a secure erase or destruction of my hard disk?
  2. Isn't there a central department at UVM which erases the data before recycling my old computer?
  3. I delete files and empty my computer's Trash or Recycle Bin to remove data. Isn't that enough?
  4. I run FORMAT or ERASE or re-partition the hard disk to remove data. Isn't that enough?
  5. How do I securely erase my hard disk?
  6. How do I get Active@ KillDisk?
  7. How do I get Apple Disk Utility?
  8. What do these terms like "One-Pass," "7-Pass" or "Gutmann" really mean?
  9. Why does a secure erase seem to take so long?
  10. Where can I find "Clean Media" labels to indicate my computer has been securely erased and is ready for recycling?
  11. What do I do with my old computer once the hard drive is securely erased?
  12. What if my old computer won't power on, its hard drive has a hardware malfunction, or something else prevents me from securely erasing it?
  13. Should I securely erase my hard drive before bringing it in for destruction?


Why do I need to do a secure erase of my hard disk?

Just like throwing away your wallet without first emptying it of your personal items, disposing of your computer and the data stored on its hard disk without first performing a secure erase or destruction compromises any personal and confidential information it may contain. Discovery of information on discarded or transferred computers could have significant legal and financial consequences for the university.

Isn't there a central department at UVM which erases the data before recycling my old computer?

No. Neither the UVM Recycling and Surplus programs nor the contracted recycling vendor perform this task or guarantee the security of sensitive data. The user of the computer and original owning department are responsible for securely erasing the hard disk.

I delete files and empty my computer's Trash or Recycle Bin to remove data. Isn't that enough?

No. Deleting files by placing them in the Trash or Recycle Bin does not actually remove any data, even when emptied. This merely tells the computer that the space those files were occupying can be used by something else, though those files you just deleted are still sitting there on the hard disk. Over time they may be eventually overwritten, but they aren't truly "gone."

I run FORMAT or ERASE or re-partition the hard disk to remove data. Isn't that enough?

No. According to LSoft Technologies, the makers of Active@ KillDisk:

If you use FDISK, FORMAT utilities, or [the] DELETE standard operating system command for data removal, there is always a chance to recover deleted data (using undelete file or some data recovery software) and use[d] against the owner's will... Active@ KillDisk conforms to [the] US Department of Defense clearing and sanitizing standard DoD 5220.22-M.

Similarly, according to Apple:

Usually when you erase a disk or volume, Disk Utility only erases the information used to access the files on the disk, not the actual files. Because of this, the erased files can be recovered.

If you want to erase the files so that they cannot be recovered, you can select security options to write zeros over the disk space. To make it more difficult to recover the files on the disk, you can specify doing this once, seven times, or 35 times.

How do I securely erase my hard disk?

Special utilities can be used to overwrite the hard disk multiple times with random data, making the recovery of documents and files from it very difficult. UVM Enterprise Technology Services recommends Active@ KillDisk for Windows PCs and Apple Disk Utility for Apple Macintosh computers.

How do I get Active@ KillDisk?

Active@ KillDisk can be downloaded and run from a CD, DVD, floppy disk or USB drive.

How do I get Apple Disk Utility?

Disk Utility comes on the Mac OS X Installer CD or DVD that came with the Macintosh when purchased. You will need OS X 10.3 or later (secure erase options are not availabe on earlier versions). A generic Mac OS X 10.3 or later CD or DVD can also be used.

What do these terms like "One-Pass," "7-Pass," or "Gutmann" really mean?

For more information on how these secure erase options differ, see Apple's documentation About Disk Utility's secure erase options.

Why does a secure erase seem to take so long?

Speed of a secure erase depends on the hard disk's size (capacity) and it's speed (rotations per minute of RPMs). A secure erase process overwrites every sector of the drive, and on today's large-volume hard disks, this can be over 1 million sectors. A multi-pass secure erase (like 7-Pass/DoD or 35-Pass/Gutmann) means going over each sector multiple times. The speed at which the drive can rotate is also a factor: a 10,000 RPM hard disk will erase faster than a 5400 RPM or 7200 RPM disk.

Where can I find "Clean Media" labels to indicate my computer has been securely erased and is ready for recycling?

Templates for printable "Clean Media" labels can be found here.

What do I do with my old computer once the hard drive is securely erased?

Follow the instructions on what to do with Computers and Electronic Wastes in the Recycling and Waste Disposal Guide. Do not throw old computers into the trash.

What if my old computer won't power on, its hard drive has a hardware malfunction, or something else prevents me from securely erasing it?

In this case, you can remove the hard drive and bring it to a central location for secure destruction. See the Hard Drive Destruction page for details. If you need assistance removing the hard drive, please contact your IT support staff or the Client Services Hardware Team.

Should I securely erase my hard drive before bringing it in for destruction?

No, you do not need to erase your drive first, as the destruction process will render the data on the drive completely unrecoverable. Likewise, if you've already securely erased the drive, you do not need to bring it in for destruction, but you may if you'd like.

Last modified June 18 2013 11:01 AM

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