When it comes to secure data destruction, establishing Trust and adhering to E-E-A-T (Experience, Expertise, Authoritativeness, and Trustworthiness) principles are the foundations of corporate data security. Whether you are handling IT Asset Disposition (ITAD), upgrading your corporate infrastructure, or selling legacy tech, the physical destruction of data storage devices is a critical step in maintaining GDPR compliance and protecting sensitive information.
But how small is small enough? Today, we are looking at the great debate in physical data destruction standards: 6mm vs. 20mm shred sizes. Does that 14mm difference actually matter for your data security? Let’s break down the physical destruction standards and what they mean for your business.
Why Physical Data Destruction Matters
In the age of sophisticated cybercrime, simply deleting files or formatting a hard drive is no longer sufficient. Physical destruction via industrial shredders ensures that hard disk drives (HDDs), solid-state drives (SSDs), and magnetic tapes are rendered entirely unrecoverable.
Choosing the right shred size is not just a logistical decision; it is a legal one. Adhering to recognised standards demonstrates to your clients and stakeholders that you take data security seriously, thereby reinforcing your brand’s trustworthiness.
The 20mm Standard: Commercial-Grade Shredding
A 20mm shred size is the industry standard for general commercial data destruction. In the context of the DIN 66399 standard, a 20mm particle size typically aligns with security level H-4 (for hard drives with magnetic data carriers).
Pros:
-
High Throughput: Industrial shredders can process high volumes of electronic waste (e-waste) quickly at this size.
-
Cost-Effective: Less wear and tear on machinery means lower operational costs.
-
Adequate for Standard HDDs: For traditional spinning hard disk drives, a 20mm shred shatters the platters enough to make data recovery practically impossible for standard threats.
Cons:
-
Inadequate for SSDs: Modern Solid State Drives store data on microchips that can be smaller than 20mm. A 20mm shred might leave entire flash memory chips intact, making data recovery highly possible.
The 6mm Standard: High-Security & SSD Shredding
A 6mm shred size is classified as high-security data destruction. Under DIN 66399, this aligns with security level H-5 (or E-5 for electronic data media like SSDs and USBs).
Pros:
-
SSD and Microchip Safe: Because flash memory chips are small, the 6mm shred guarantees that the individual data-storing chips are physically pulverised.
-
Maximum Security: Ideal for top-secret, financial, government, or highly classified corporate data.
-
Ultimate Trust: Utilising a 6mm shredder provides the highest level of E-E-A-T in your data handling protocols.
Cons:
-
Slower Processing: Achieving a smaller particle size requires more time and energy.
-
Higher Equipment Costs: Machinery must be highly robust, and the cutting shafts wear out faster, requiring more maintenance.
The Verdict: Does Shred Size Matter?
Absolutely. The leap from 20mm to 6mm is the difference between standard compliance and bulletproof data security.
If your company primarily disposes of older, magnetic HDDs, a robust 20mm industrial shredder will meet your GDPR obligations and keep your data safe. However, as the world pivots entirely to SSDs, NVMe drives, and microchip-based storage, upgrading to a 6mm shredding capability is becoming a mandatory requirement to maintain trust and protect against data breaches.
At Surplex UK Limited, we understand that having the right machinery is the backbone of industrial operations and IT asset recycling. Whether you need high-torque twin-shaft shredders for 20mm commercial processing or granulators for 6mm high-security destruction, sourcing quality used industrial equipment can help you scale your operations cost-effectively.
Frequently asked questions
It matters for solid-state media and matters less for spinning hard drives. A platter broken into large fragments is unreadable; NAND flash chips are small enough to survive a coarse shred intact.
So the right question is not which size is best in general, but which size is right for the media you are destroying.
The particle size the material is reduced to. 20mm is commercial-grade and appropriate for traditional hard drives. 6mm reduces media to a particle small enough to destroy the individual memory chips in solid-state drives.
Surplex UK Limited shreds to 6mm where solid-state media is involved.
A particle size small enough to destroy the NAND chips themselves rather than merely separating them from the board. In practice that means 6mm.
A coarse shred can leave a chip physically intact, and an intact chip is a recoverable one.
BS EN 15713:2023 is the British and European code of practice for secure destruction, covering how material is collected, transported, destroyed and evidenced. NIST 800-88 defines Destroy and Purge as sanitisation methods.
Surplex UK Limited works to both, and issues a certificate of destruction against each device serial number.
Focused Disposal & Data Security
Comprehensive IT Solutions

Get in Touch About Your IT Recycling Needs
We provide IT recycling services for organisations of all sizes across England, Wales and Scotland.
Whether you’re recycling a few old laptops, decommissioning a data centre, or need secure data destruction, our team will help you dispose of IT equipment compliantly and responsibly.
Prefer to speak with us directly?
Call: +44 (0)1684 252583
Email: info@surplex.co.uk
Monday-Friday, 9am-5pm




