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Sicherheitsstufe H-5
"Destruction in accordance with DIN 66399, security level H-5" – this requirement appears in many data protection concepts and tenders. What exactly is behind the abbreviation, for which data is it sufficient, and where are its limits? This glossary entry puts H-5 in context.
In brief
Security level H-5 is a destruction level of the DIN 66399 standard for hard drives with a magnetic storage medium. The hard drive is divided and deformed several times so that the particles are at most 320 mm² in size, about as large as a postage stamp. H-5 is suitable for hard drives with sensitive and confidential data and covers protection classes 2 and 3.
What does H-5 mean?
DIN 66399 describes how data carriers are physically destroyed. It works with three building blocks: the protection class for the protection requirement of the data, the material class for the type of data carrier, and the security level for the degree of shredding. The "H" stands for the material class H, that is, hard drives with a magnetic storage medium (HDD). The "5" is the security level on a scale from 1 to 7.
| Level | Requirement for hard drives (simplified) |
|---|---|
| H-3 | Data carrier deformed |
| H-4 | Deformed and divided several times, particles ≤ 2,000 mm² |
| H-5 | Divided and deformed several times, particles ≤ 320 mm² |
| H-6 | Particles ≤ 10 mm² |
| H-7 | Particles ≤ 5 mm² |
The complete overview of all levels and classes can be found in the entry Security level (DIN 66399) and in our guide DIN 66399: Which safety level your hard drives need.
For which data is H-5 suitable?
The standard assigns each Protection class a range of security levels. Protection class 2 stands for high protection requirement and covers levels 3 to 5. Protection class 3 stands for very high protection requirement and covers levels 4 to 7. H-5 lies in both ranges. The level is therefore suitable for hard drives with personnel and customer data, contract documents, or confidential business data.
Which protection class applies is decided by your company, not the service provider. The basis is an assessment of the protection requirement of your data.
Key takeaway: H-5 applies to magnetic hard drives. For SSDs, USB sticks, and memory cards, a level of material class E is needed.
H-5 and SSDs
An SSD stores data in small flash chips. A particle of 320 mm² can contain an entire memory chip. That is why DIN 66399 assigns SSDs to material class E, with significantly smaller particle sizes. Anyone who has mixed stocks of HDDs and SSDs destroyed should have the levels for both material classes stated separately. How the size of the particles is determined is explained in the entry Particle size.
Destroying is not always the best way. Functional hard drives can be erased with certification and continue to be used. When erasing and when destroying is worthwhile is shown by our guide Hard drive destruction: costs and alternatives.
Security level H-5 at Second IT
Second IT destroys data carriers in-house in accordance with DIN 66399 and is certified for security level H-5 for this. The destruction is under video surveillance around the clock and takes place without transport to external sites. Before destruction, the data carriers are stored in security zones with controlled access. Every data carrier is registered by serial number, and you receive a certificate of destruction. The residues are separated and recycled. More on the in-house data carrier destruction.
Frequently asked questions about security level H-5
How large are the particles at H-5?
At most 320 mm² per particle. That corresponds roughly to the area of a postage stamp. The hard drive is then divided and deformed several times.
Is H-5 enough for personal data?
For hard drives with personal data, protection class 2 is usually appropriate. It covers levels 3 to 5, so H-5 meets it. With very high protection requirement (protection class 3), H-5 also lies within the permitted range.
Does H-5 also apply to SSDs?
No. SSDs belong to material class E and need an E level with smaller particles. Have the levels for hard drives and flash storage confirmed separately.
Who decides which protection class applies to my data?
Your company decides that, not the service provider. The basis is an assessment of the protection requirement of your data. Only then can the appropriate security level be chosen, for example H-5 for hard drives with high or very high protection requirement.
Does every hard drive have to be destroyed to H-5?
No. Functional hard drives can be erased with certification and continue to be used. Mainly data carriers that cannot be erased securely, or for which your requirements demand it, are destroyed. When what is worthwhile depends on your erasure concept.
Destroy hard drives to H-5 – in-house, with a certificate per serial number.
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