Securely Deleting Electronic and Paper Records

University of Florida Privacy Policy and Security Policy requires the secure destruction of paper and electronic records and media containing Restricted Data. Note that destruction of Primary Records are subject to UF Records Retention requirements, and must follow the UF process for Disposal of Records. Secondary Records may be destroyed as soon as they become obsolete, superseded or administrative value is lost (OSA).

Different media types require different destruction methods which also vary by the intended re-use of the media. Be aware that deleting a file, even using a method described below, will not remove other copies of the file, including duplicates or backups on the same drive, copies on other media, and copies stored in backup systems or drives.

Media that will be re-used within the same unit can either be Cleared or Purged.

Media that will be transferred to another unit, disposed of, or otherwise removed from control of the unit can either be Purged or Destroyed.

Purge and Destroy methods are acceptable when Clear is specified, and Destroy is acceptable when Purge is specified.

Media type Clear Purge Destroy Notes
Paper NA Shred, pulverize or incinerate Use either a cross-cut shredder, or use a certified shredding service
Individual Files stored on a hard drive Overwrite using a secure erase utility NA PGP Shredder (installed as part of PGP Desktop), Heidi Eraser, Windows ‘sdelete‘, OSX ‘Secure Empty Trash
Individual files stored on an encrypted hard drive or encrypted flash drive Normal OS file delete is sufficient NA Must be encrypted according to the Mobile Computing and Storage Devices Standard.
CD (including R and RW) and DVD (including R and RW) NA Incinerate or shred
Mobile phones, smartphones, tablets Use the ‘Erase All Content’ feature Shred or incinerate Verify with manufacturer that the feature securely erases data or performs a complete Cryptographic Erase (all storage is encrypted and the erase function destroys the encryption key). Apple iOS, Blackberry, and most versions of Android support secure erase.
Magnetic tape, floppy disks, ZIP disks Overwrite data Degauss Shred or incinerate
Magnetic hard drives Single-pass overwrite ATA Sanitize, ATA Secure Erase, SCSI Sanitize or degauss Shred or incinerate Single-pass overwrite using utility such as DBAN or Heidi Eraser. ATA Sanitize and Secure Erase supported by HDDErase or hdparm. SCSI Sanitize supported by sg_sanitize. Secure Encrypted Drives may be cleared or purged using Cryptographic Erase.
Damaged or non-functional magnetic hard drives NA Degauss Shred or incinerate
ATA Solid State Drives Single-pass overwrite or ATA Secure Erase  ATA Secure Erase or Cryptographic Erase  Shred, pulverize or incinerate
 Flash-based removable media (USB flash drives, SD cards, etc) Multi-pass overwrite manufacturer supported Purge functionality, or destroy.

References:

UF Information Privacy Policies and Procedures

UF Records Management

UF Media Sanitization Standard

NIST SP800-88