Skip to content 
Sicherheitsstufe (DIN 66399)
In brief
The security level under DIN 66399 indicates how thoroughly a data carrier is shredded during destruction. The standard has seven levels from 1 (general data) to 7 (top secret data); the higher the level, the smaller the particles and the greater the effort required for reconstruction. Which level fits results from the protection requirement of the data and the type of data carrier.
The seven security levels at a glance
- Levels 1 to 3: for general, internal, and sensitive data. Reconstruction is to be made difficult or possible only with considerable effort.
- Levels 4 and 5: for particularly sensitive and confidential data. Reconstruction is to be possible only with extraordinary effort or with special equipment.
- Levels 6 and 7: for secret and top secret data with the highest requirements.
The level is stated together with the Material class , for example H-5 for hard drives. The permitted particle size differs depending on the material class.
How to find the right level
| Protection class | Need for protection | Permitted security levels |
|---|---|---|
| 1 | normal | 1 to 3 |
| 2 | High | 3 to 5 |
| 3 | very high | 4 to 7 |
First you determine the Protection class , then the level results from the material class. For hard drives with personal data, Security level H-5 is often chosen. The complete table with particle sizes can be found in our guide DIN 66399: protection classes and security levels.
Second IT destroys data carriers in-house in accordance with DIN 66399, certified for security level H-5, and documents every destruction with a certificate.
Frequently asked questions about the security levels
How many security levels are there in DIN 66399?
Seven, from level 1 for general data to level 7 for top secret data.
Which security level do I need for personal data?
Usually protection class 2 with levels 3 to 5. Many companies choose level 4 or 5 for hard drives.
Does the same level apply to hard drives and SSDs?
The number can be the same, the requirement not. SSDs belong to material class E and require smaller particles at the same level.
What does security level H-5 mean under DIN 66399?
The H stands for the material class hard drives, the 5 for the security level. Level 5 is intended for particularly sensitive and confidential data. Reconstruction is to be possible only with special equipment. H-5 is often chosen for hard drives with personal data.
What is the difference between protection class and security level?
The protection class describes the protection requirement of the data: normal, high, or very high. The security level indicates how thoroughly the data carrier is shredded during destruction. You first determine the protection class. The permitted security levels follow from it.
Destroy data carriers in accordance with DIN 66399 – in-house, with a certificate per serial number.
Send us your device list. You will receive your offer in 48 hours on average.