Cleanroom Services

Cleanroom Classes

Cleanrooms are divided into cleanroom classes (or purity classes) depending on the particle density. They are subject to strict, standardised requirements for the maximum permissible particle concentration (particles per m3) and are classified according to the degree of air purity. The limit values are specified in the relevant standards and guidelines DIN EN ISO 14644-1 and EC-GMP Guide, Annex 1.

To determine the cleanroom class, particle measurements are taken after the construction of a cleanroom. Even during operation, the systems must be checked on regular basis. We carry out qualifications or requalifications and provide proof that your cleanroom meets the relevant limit values.

Cleanroom classes according to DIN EN ISO 14644-1

Classification of purity classes according to DIN EN ISO 14644-1:2015

Purity Classes ISO-14644-1
The ISO standard is frequently used within medical, optical and laser technology as well as micro-electronics and micro-mechanics, automotive and other industrial sectors.

The standard DIN EN ISO 14644-1 divides cleanrooms into classes ISO 1 to 9. Purity class 1 is the purest, meaning the maximum permitted particle concentration is at the lowest possible level. Class 9, on the other hand, denotes high impurity. For most applications in the ISO range, cleanroom classes 7 and 8 are sufficient. ISO Class 5 complies with purity class A according to the EC-GMP guideline and meets particularly high purity requirements.


Cleanroom classification according to the EC GMP Guide, Annex 1

Purity Classes GMP-Guideline
The EC GMP Guide, Annex 1, is mainly used in sectors where "Good Manufacturing Practice (GMP)" is of central importance. These include pharmacy, biotechnology, medical technology, the food and cosmetics industries and several others.

The EC-GMP Guide, Annex 1 defines the cleanroom classes A, B, C and D. Class A has the highest/purest level while cleanroom class D allows the largest maximum permissible particle concentration and is therefore the lowest. Up to class A, no purity classes may be skipped. Class D must pass through class C and B to operate in cleanroom class A.


You would like to have your cleanroom classified or have questions about the cleanroom classes?

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Read more about cleanroom qualifications