Fan-Filter-Module (FFU) and their applications


The term "tools for clean air" is used to describe units for clean air supply such as various Fan-Filter-Modules and Clean Air Modules SRM. We will give you an overview of how FFUs (Fan-Filter-Units) are constructed and which special features distinguish our devices. The Fan-Filter-Units are the active elements in cleanrooms, clean air workstations, minienvironments or clean transport systems and should therefore be selected to suit the application. Here we help you to make the right choice.

What are Fan-Filter-Units and how are they constructed?

Since the mid-1980s, Fan-Filter-Modules have been available on the market under the term FFU, which stands for Fan-Filter-Unit and represents a compact unit for the generation of high-purity air. These units made it possible for the first time to bring greater flexibility into the air flow in cleanrooms. The possibility of controlling the modules individually made it possible to flexibly vary the air discharge velocities under the filters within a room. It was no longer necessary to use filters with different pleat heights and thus variable differential pressures, which was also a rigid and not a flexible system.

At that time, these first units were mainly available in a few standard sizes, which were mainly oriented to the outer dimensions of 300, 400, 600, 900 and 1,200 mm. When used in various cleanroom ceiling grids, these dimensions could deviate downwards to reach ceiling grid dimensions of 600, 900 and 1,200 mm. These, however, quite limited dimensions reduced the use mostly only to cleanroom ceilings and cleanroom cabins.



Since then, the development of Fan-Filter-Modules has experienced a strong upswing. There are many suppliers worldwide whose units differ in details or even fundamentally from those of other suppliers.

In addition, the usage possibilities have expanded to other areas such as minienvironments, glove boxes and mobile systems. The field of (customer) machine-integrated solutions has also developed strongly.

At this point, we would like to discuss some designs that deviate completely from the basic design. Standard dimensions, which are limited to a few dimensions in length x width, are no longer an issue.

Flat Design

Previous units had an overall height of 350, 400 or even more mm. This is quite acceptable for conventional using, above all because the sound levels in these modules can be reduced by large fans on the one hand and sound-absorbing linings on the other.

However, many uses also require low installation heights. It is possible that cleanrooms and cleanroom cabins have to be installed in existing rooms with insufficient ceiling heights. These are uses in minienvironments and also special applications in places where space is extremely limited.



200 mm high modules in various dimensions

This patented solution uses the housing of the HEPA filter, which is very well suited due to its anodized surface, as the housing of the module. In addition to material savings, a weight reduction is also achieved, which should further expand the range of applications.

Fan-Filter-Module FFM-C

For particularly clean environments we also offer a complete unit made of brushed stainless steel:

Fan-Filter-Module FFM-E

Integrable FFU

Specially developed modules are available for the installation or mounting of FFUs in or on machines and systems. 

Integrable FFUs

The advantage of these modules is that the dimensions of the pressure frame for the filter can be designed completely variably and independently of the filter size, thus creating plug & play solutions that save the user additional design effort and additional components.

6-sided integrable FFUs

Thus, for example, hexagonal modules can be created for installation in cluster tools, making additional adapter plates superfluous.

Integrable FFU with two filters

In order to achieve different air discharge velocities within a machine, which can be necessary for flow optimization, several HEPA filters can also be integrated into a single module in the integrable FFUs.

Integrable Fan-Filter-Module

Especially when Fan-Filter-Modules have to be mounted directly at the point-of-use, they should be particularly easy to integrate into the overall system. Our FFM-S can, be placed directly on a robot arm or on the wafer handling system, for example.

Fan-Filter-Module FFM-S


At this point a few examples of special solutions shall be described, which shows many possibilities of the use.


FFUs with black housing and black filter surface

In optical manufacturing, for example, the quality of the optics in a dark room is checked using a light source. These test rooms must be very dark in order to detect defects in the surfaces. If this also has to be done under cleanroom conditions, it is easy to black out walls, ceilings and floors. However, the filter surfaces of the HEPA filters used are always white.

This patented solution reduces light reflection at the filter surface by 95%.

Fan-Filter-Module FFM-C (black)


Special solution with chemical filtration

In museums it is often necessary to protect particularly valuable exhibits not only from particles, but also from chemical influences. Since a very compact design is also important in showcases, this was implemented in a module, which contains chemical filters for a wide variety of harmful airborne compound, in addition to the particle filter.

Special solutions



Clean Air Module

With this a high air volume in a sufficient purity at low running costs is achieved. However, the use of these modules is not limited to the automotive industry.

The automotive industry is currently one of the biggest drivers of developments in the field of technical cleanliness. The main focus here is on partial cleanliness. However, the cleanliness produced must be maintained by an appropriate environment. Surely one does not necessarily speak today of the extensive use of pure areas in the automobile industry, but the term clean area is already in all heads. Since cleanrooms that do not reach the cleanroom level are primarily concerned with reducing running costs, there are so-called Clean Air Modules that are equipped with a high-quality F9 pre-filter instead of a particulate air filter.

Clean Air Module SRM

In summary, it can be said that the using areas of the Fan-Filter-Modules FFU are almost unlimited. One should not limit oneself to a limited range of standard modules. Customer-specific solutions make it possible to save high follow-up costs in the continuing value chain, which can arise through the use of very inexpensive standard modules.

COLANDIS has got the right solution for every application

Our Fan-Filter-Modules are individually adapted to your requirements in the cleanroom or the clean environment. In addition, we not only supply you with suitable modules, but also help you to achieve intelligent flow control. In most cases, the air is discharged from the FFUs via the ceiling to the cleanroom. This filtered air must also be sucked off again and reprocessed. A circuit that is as effective as possible is therefore only created when the air is sucked in via the floor or the lower side elements.

Due to the high quality and the long-term use of our modules, we can guarantee you continuous support of the FFUs.


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