The History and Science of Degaussers

November 6, 2019 at 7:15 pm by Paul Falcone

Degaussing is a familiar word to those who work in the data destruction industry, military, or who work with magnetic media, but the science and history behind these machines may be lost to many. The truth is the concept of degaussing has been toyed with since the late 1800’s, and its implementation and uses have stretched around the world, across numerous world wars, and is currently used across a variety of industries and fields.

With the introduction of iron ships in the late 1800s, scientists and crew members began to take notice of the effects that new metal ships were having on compasses. Over the years, this was experimented with and explored until the first “degausser” system was installed on a warship by a Canadian chemist, Commander Charles F. Goodeve, for the British in World War II.

The discovery came after a counter measure was required to stop German mines from detonating in the water. In 1939, a poorly targeted German mine hit a beach in Britain that specialists were able to disarm and research. It was discovered that the mines had a device that would trigger detonation based on the surrounding gauss level, which is a unit of measuring magnetic density and named after Carl Fredrick Gauss. This meant that once a magnetically dense and charged metal ship entered the radius of the mine, it would automatically detonate and cause catastrophic damage to the ship. It was this discovery that Goodeve and his team used to develop and coin the term “degausser” which was then used on naval ships against the Germans for the rest of the war.

Carl Gauss

To degauss the ships, a system was implemented that installed electrical cables around the circumference of the ship’s hull all the way from the bow to the stern. Then an electrical current was sent through the cables that neutralized the magnetic field on the ship, rendering the ship degaussed. This discovery allowed the ships to pass by the enemy mines without them sensing a gauss level and detonating. They could also “wipe” a ship, which would remove its magnetic field for a few months, until a magnetic field was built up again.

After the war, the technology was expanded upon and used to “erase” data that was stored on tape and magnetic devices. Once computers and rotational hard drives became prevalent, degaussing became the de-facto way to ensure that sensitive data is erased and cannot be recovered. After this history, it makes sense that degaussing removes a magnetic field, but how does this affect the data that is stored on a device?

The magnetic field that is created by these storage devices is actually what also holds the data and information. The information saved is placed in a certain pattern within the magnetic field, allowing large quantities of information to be stored and accessed at the request of the user. This is why a degausser is such a trusted way to ensure data has been completed erased. When a magnetic hard drive is degaussed, the magnetic field around the drive is completely scrambled. The data that existed on the drive is split, rearranged, and stitched back together multiple time as the field that comes out of the degausser is completely unknown from the one that entered.

To give an idea of how much energy is actually used in some of these degaussers, a SEM Model EMP1000-HS will zap a drive with 2.0 Tesla (20,000 gauss), the mandated amount by the NSA to securely and confidently destroy HDDs with top secret and classified information. After putting a drive in one of these machines, the field can be completely destroyed in just seven seconds, making sure that no information can ever be stored or accessed again.

emp 1000HS
SEM’s NSA listed Model EMP1000-HS degausser is an ideal solution for rotational hard drives.

Today, degaussing equipment is still used on naval warships to evade enemy detection by gauss level. Media degaussers are also equipped on many of these same ships, but it doesn’t stop there. Other military branches, executive branches, data centers, and hospitals around the world will all often house some form of data destruction for these devices, and if it’s being done safely and securely, a degausser is present. Thanks to Charles Goodeve, his team, and a poorly launched German mine, degaussing now exists, and its technology and effectiveness will continue to be used for a long, long time.

NIST Guidelines vs. the NSA EPL on Hard Drive Destruction: Clearing Up Confusion

February 5, 2019 at 5:44 pm by Heidi White

hard drive destructionOver the 20 years I have been working for SEM, I have explained to customers and former military colleagues about the requirements for classified destruction. Lately these requirements have become stricter due to the ever-changing technologies. It’s not as easy as just putting your paper in a shredder or disintegrator and walking away knowing your classified is destroyed. Your classified now comes on many types of media. With so many types of media, a requirement had to be set forth by the National Security Agency (NSA) as to how these needed to be destroyed. We will discuss destroying hard drives as it relates to the National Institute of Standards and Technology (NIST) 800-88 and NSA Evaluated Products List (EPL) for Hard Drive Destruction.

For this blog, I will only discuss a brief overview for the destruction of hard disks (SCSI, ATA, SATA). NIST 800-88 explains on page 16, table 5-1 there are three methods of destroying hard disks. The first is to CLEAR. This method uses software to overwrite the storage space on the media with non-sensitive data (unclassified) and gives you the option to reuse your hard drive. The second is to PURGE. This method uses degaussing and the Secure Erase command present on some ATA drives. This method is very effective again for unclassified drives. The third method is PHYSICAL DESTRUCTION. This method is the standard for classified data and it destroys the drive by using disintegration, pulverization, melting, or incineration.

emp 1000HS
SEM’s NSA listed Model EMP1000-HS degausser is an ideal solution for rotational hard drives; however, degaussing has NO effect on solid state media.

The second paragraph of the NSA/CSS EPL for Hard Drive Destruction Devices states, “Hard drive destruction devices on their own DO NOT SANITIZE magnetic and/or solid-state storage devices; use of these machines is only authorized in conjunction with degaussing for routine magnetic hard disk drive sanitization or by themselves only in extreme emergency situations. Sanitization guidance for classified storage devices is located in the NSA/CSS PM 9-12 Storage Device Sanitization Manual.” This leads you to believe that degaussing could be used on a solid state drive (SSD). This is misleading! A magnetic field created by a degausser will cause no damage to an SSD. A degausser will only destroy information on a standard rotational magnetic drive.

ssd shredder
Classified SSDs must be disintegrated to a 2mm particle size.

In the third paragraph it states; “All shredders designed for hard drives are approved for deformation of magnetic hard drive platters. Shredding alone will NOT SANITIZE magnetic and/or solid state storage devices unless a two-millimeter particle size or less of the magnetic disk or solid-state memory chip is accomplished in accordance with NSA/CSS PM 9-12 Storage Device Sanitization Manual.” This states that if you have a hard drive or SSD, you can shred it to a 2mm particle to sanitize the drive. This is confusing. Although the NSA guidelines REQUIRE you to reduce a classified SSD to a two-millimeter particle to render the device sanitized, the machine that does this may not be able to shred a standard magnetic hard disk drive to this two-millimeter particle. This is due to the size and materials used in the manufacturing of a magnetic hard disk.

In conclusion, in order to completely destroy the information in a hard drive is a two-step process for a magnetic hard drive and a single step process for a SSD.

A magnetic disk MUST BE degaussed using an NSA approved degausser THEN physically destroyed. This second step of physical destruction is left up to the end user and can vary greatly. It can be as simple as drilling a hole in the drive, hitting it several times with a hammer, or using a hydraulic punch or hard drive shredder. A solid state drive MUST be shredded to a two-millimeter particle and cannot be degaussed.

If you have any questions or would like to talk to a security professional, feel free to reach out to me or any SEM representative.

Karl Lotvedt, DC Region Sales Support, has over 20 years of experience with SEM, including targeted expertise in understanding military procedures and requirements. Prior to joining SEM, Karl spent 20 years in the United States Air Force including over five years in procurement. Now retired from the Air Force, Karl currently serves as an Air Force resource advisor. Karl received his AA and CIS from National College in Rapid City, SD.

Non-Government Organizations – Are You Required to Destroy Magnetic Media?

November 29, 2018 at 3:53 pm by SEM

Many organizations or companies, that have no connection with state or federal government agencies, possess large amounts of information that reside on hard drives, backup tapes, and a variety of other magnetic media that contains extremely sensitive information. Depending on the nature of your business, much of this data requires complying with strict industry standards. It is difficult to mention all of the industry standards that are out there, but here are a few that may apply to your business: HIPAA (Health Insurance Portability and Accountability Act), FERPA (applies mostly to colleges and universities), FACTA (Credit Transactions Act), and Sarbanes Oxley Act and PCI DSS (Payment Card Industry- Data Security). Non-compliance on the part of your organization could result in fines or expose your company to criminal and civil liabilities.

Growing Need for Proper Media Sanitization & Destruction: Why Degauss?

emp 1000HS
SEM’s NSA listed Model EMP1000-HS degausser is an ideal solution for rotational hard drives; however, degaussing has NO effect on solid state media.

Media sanitation and destruction is the one thing you can control internally to guarantee total confidentiality for your organization. Computer technologies are changing every day, creating more powerful computers with track densities that make previous methods of destruction totally obsolete. Degaussing is a method that exposes the magnetic media, like hard drives and backup tapes, to a powerful magnetic field. This method not only destroys the media but also the firmware that manages the device. Some of the more prominent high security IT organizations and test facilities in the U.S. prefer this method of destruction over all others.

Is Physical Destruction Really Necessary?

Some people consider physical destruction the ultimate form of media destruction. Physical destruction of hard drives can be accomplished by shredding, crushing, or using a device that bores a hole in the center of the drive creating severe damage to the housing and internal workings of the drive. Incineration and melting will also destroy media, but these methods may be impractical or unavailable to your average company. Most physical destruction devices have a relatively small footprint and can be located in your IT department or in a designated area within the company. Depending on the importance or security categorization of your data, you might consider a two-step process where degaussing and physical destruction go hand-in-hand. Most government agencies are dealing with extremely sensitive data, which requires degaussing and some form of physical destruction. This is something to seriously consider with the increasingly sophisticated level of encryption that is out there today.