Cleanroom technology

I. Cleanroom systems in hospitals and medical technology

Extension of the HVAC technology

HVAC systems for hospitals and for employment in medical technology are an extension of the classical HVAC technology, because they must meet far higher demands on purity.

Employment of HEPA filters

In case of a mostly two-step air-supply filtration, which can be manufactured with (among other things) fine dust bag-type filters as well as with fine dust compact filters, HEPA filter stages additionally extend the cleaning effect. As a result of this, supply air considered as particle-free and germ-free can be provided in operating rooms. For clarification: The cleaning effect of HEPA filters is over 1,000 (e.g. HEPA H13/EN 1822) to 10 million (e.g. HEPA U17/EN 1822) times higher than in case of an F9 fine dust filter.

Why is a high level of air purity necessary?

Patients in hospital are especially in need of protection, so that a very high level of air purity is important. At the same time, however, the transfer of microscopically small pathogenic agents to healthy persons must also be prevented. And also the handling of medication and medical devices requires the highest level of air hygiene, for the air technology as well as for the personnel in the hospital.

Filter types used in hospitals:

1. Filter stage
Fine dust bag-type filtersMULTIFOLD Pocket Filter TCC 85 – TCC 98
Fine dust compact filtersCompact Filter RELM VRK
Compact Filter FLUWID VSK
2. Filter stage
HEPA filtersHEPA-Filter Panel


II. Cleanroom systems in pharmaceutical technology

High air purity for the protection of persons and products

In the pharmaceutical industry, extreme air purity in the production process is of great importance. Here, highly-effective materials are manufactured under very constant ambient conditions, that may not be contaminated or damaged and may not reach the environment. In addition, protection is to be guaranteed to the employee against contact with pharmaceutical products.

Categorisation into cleanroom classes

Therefore pharmaceutical production occurs mainly in clean rooms which belong to different cleanroom classes, according to process and required particle purity. While in so-called “grey rooms”, the lowest cleanroom class, approx. 3.5 million particles (0.5 µm size) per cubic meter are allowed to be present, in the highest class this figure is less than 10 particles per cubic meter.

Cleanroom through correct filter arrangement

These extreme levels of purity are achieved through a multi-level, cascaded filter arrangement with high-quality ULPA filters, where the finish-cleaned process air enters the clean room via ceiling filter elements at very low air speeds. There also exist arrangements with circulating air filters or with decentralised island solutions, where a higher level of purity is adjusted within the island than in the entire clean room environment.

However, cleanroom conditions depend not only on perfect filter performance. Particle sources within the clean room, as well as cross-mixing between individual processes, are also to be avoided, so that a laminar, low-turbulence air flow must always be maintained. This in turn can be guaranteed only by optimum layout, filter arrangement, constant monitoring of the states and qualified personnel. It is obvious that many factors are to be considered. Similar conditions are also to be provided in semi-conductor and electronics manufacture, in medical and space technology.

Filter types used in pharmaceutical technology:

Fine dust bag-type filtersMULTIFOLD Pocket Filter TCC 85 – TCC 98
Compact filtersCompact Filter RELIM VRK
Compact Filter FLUWID VSK
Compact Panel Filter PB-95
HEPA filtersHEPA-Filter Panel
HEPA-Filter Cell
HEPA-/ULPA-Filter Panel