Hard Disk Degaussing: Is It the Right Way to Wipe Data?

When it’s time to dispose of old hard drives, simply erasing  files or formatting the disk isn’t enough to keep sensitive information out of the wrong hands. One method that often comes up is degaussing - but is it really the most secure way to wipe your drives?

In this post, we’ll unpack what hard disk degaussing  is, how it works and why it may not be enough to meet today’s data protection standards. 

We’ll also explore why many organisations, including Shred-it, choose the certainty of physical hard drive destruction instead.

What is Hard Disk Degaussing?

Hard disk degaussing is a data destruction method that uses strong magnetic fields to scramble the magnetic domains on a hard disk drive, effectively erasing the data stored on it. Originally developed for wiping magnetic tapes and traditional hard drives, It’s still used  by organisations that handle sensitive information and need to render data unreadable.

When a device is degaussed, the magnetic patterns that store data are disrupted, making it nearly impossible to retrieve the original files. But while that sounds impressive, the reality is more nuanced.

For starters, degaussing only works on magnetic media like traditional HDDs or tape drives. Solid State Drives (SSDs), which rely on flash memory rather than magnetic fields, are immune to degaussing altogether. So if your organisation relies on modern storage technology, degaussing may be useless for you.

In short, degaussing is a legacy solution which can be effective for certain types of media but  not a universal solutionIt leaves the physical device intact introducing other risks - which we’ll explore next.

How Does Degaussing Work?

Degaussing works by exposing a magnetic storage device like a hard disk drive, to a high-intensity magnetic field. This field disrupts the magnetic domains on the disk platters, which are what store the data. To carry this out, organisations use a machine called a degausser. These devices vary in strength and type but all serve the same core function: to generate a magnetic force to wipe data. 

It can be a quick process, usually just a few seconds, but it requires specialised equipment and often certification to ensure it’s done correctly.

However, it’s not foolproof:

• It won’t work on solid-state drives (SSDs) which store data using flash memory rather than magnetic fields.
  
  

• The device remains physically intact which means it could still be reused or tampered with if not properly disposed of.
  
  

This is why physical destruction remains the preferred choice for many businesses seeking absolute data elimination.

Is Degaussing Enough?

While degaussing can be effective at removing data from magnetic media, it doesn’t always guarantee complete or compliant data destruction, especially in today’s evolving digital landscape.

As data security standards become more stringent and storage technologies more diverse, relying solely on degaussing may leave gaps in protection:

1. No Physical Destruction
   The hard drive remains intact. This means the hardware could potentially be reused, resold, or stolen - introducing a physical security risk.
   
   

2. Not Compatible with SSDs
   Degaussing only works on magnetic storage. SSDs, which are widely used today, are completely unaffected by magnetic fields. Trying to degauss one won’t do a thing.
   
   

3. Lack of Visual Proof
   After degaussing, there’s no obvious sign that the drive has been wiped. This makes it harder to prove that destruction has occurred, especially during audits or compliance checks.
   
   

4. Regulatory Uncertainty
   Certain data protection standards, like GDPR or HIPAA may require destruction methods that provide a clear chain of custody and proof of destruction. Degaussing alone might not tick those boxes.
   
   

For businesses requiring uncompromising data security and regulatory compliance, relying solely on degaussing poses potential risks. That's where physical destruction emerges as a more conclusive and broadly recognised solution for ensuring complete data elimination.

In fact, the National Cyber Security Centre (NCSC) in the UK recommends physical destruction of hard drives when sensitive data must be irreversibly destroyed, particularly when devices are no longer needed or being decommissioned.

Degaussing vs. Hard Drive Destruction

While degaussing can erase data from magnetic hard drives, it comes with significant limitations: it’s ineffective on SSDs; leaves the device physically intact; and provides no definitive proof that data has been fully deleted.

That’s why physical hard drive destruction, like the service Shred-it provides, is a gold standard. It destroys the device completely, works on all drive types, and gives you the peace of mind (and proof) that your data can never be recovered.

Why Shred-it Recommends Hard Drive Destruction