DIN 66399 Material Classification H refers to information on hard drives with magnetic data carriers. The Security Levels run from H-1 to H-7 with H-1 being recommended for data carriers with general data which have to made illegible, to H-7 for data carriers with top secret data where the strictest security standards must be maintained.

H1

• Recommended, for example, for data carriers holding general data to be rendered illegible
• Particle size: mechanically/electronically inoperable
• Shredded data can be reproduced without special knowledge or equipment, although the process is time-consuming

H2

• Recommended, for example, for data carriers holding general data to be rendered illegible
• Particle size: damaged
• Shredded data can be reproduced with equipment, although the process is time-consuming

H3

• Recommended, for example, for data carriers holding sensitive, confidential and personal data
• Particle size: Deformed
• Shredded data can only be reproduced with maximum effort and special equipment

H4

• Recommended, for example, for data carriers holding particularly sensitive, confidential and personal data
• Max. material particle size 2000 mm²
• Shredded data can only be reproduced utilizing equipment that is not readily available commercially

H5

• Recommended, for example, for data carriers holding confidential information
• Max. material particle size 320 mm²
• Shredded data is unlikely to be reproduced even with special equipment

H6

• Recommended, for example, for data carriers holding confidential information demanding an exceptionally high level of security
• Max. material particle size 10 mm²
• Shredded data cannot be reproduced even with special equipment

H7

• Recommended, for example, for data carriers holding strictly confidential information demanding the highest security precautions (e.g. classified and top secret)
• Max. material particle size 5 mm²
• Shredded data cannot be reproduced in any way with the current state of science and art