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Filter measurement and replacement
Be on the safe side
with your production
We can advise you on all aspects of filter replacement and carry this out without causing contamination
Filter measurement in your cleanrooms
HEPA filters and a variety of coarse and fine filters for pre-filtration are predominantly used in the cleanroom. Adsorption filters are also increasingly used to separate airborne gaseous molecules and reduce AMC (Airborne Molecular Containment) - especially in the semiconductor industry and pharmaceutical and medical technology.
The classification and testing of particle filters is based on the European filter test standard EN 1822. Decisive for the classification is the filtration efficiency of the filter, which is calculated from the mean value of random measurements. High-performance HEPA filters achieve separation efficiencies of up to 99.99995%.
Why are filter replacements necessary?
After a certain operating period, the performance of the filters inevitably decreases. Replacement or exchange of the units becomes necessary in order to continue to guarantee the required particle-free conditions of the respective cleanroom class. We can advise you on all aspects of filter replacement and perform a change for you without causing contamination.
The European filter test standard EN 1822-1:2009 distinguishes between three groups of particle filters:
- Group E: EPA filter – High-performance particle filter (Efficient Particle Airfilter)
- Group H: HEPA filter – particle filter (High Efficiency Particle Airfilter)
- Group U: ULPA Filters – High performance HEPA filter (Ultra Low Penetration Airfilter)
We would be happy to advise you
Always individual, personal, competent and without obligation.
These companies rely on us
Filter fan unit (FFU)
Filter Fan Units (FFU) draw air from the environment and from the cleanroom and blow the air, which is filtered to a certain quality, back into the room. To be able to do this, they feature a pre-filter and a HEPA filter, which is designed to reliably achieve the defined filtration efficiency according to EN 1882 at all times. The components are compactly installed in an aluminium or powder-coated sheet steel housing. Optionally, coolers installed in the housing can cool the return air to the desired temperature and dry it to avoid condensation.
A corresponding number of FFUs are installed in the ceiling system and interconnected via a central control unit. In this way, the defined setpoints for temperature and air flow can be continuously maintained throughout the room. The FFUs' exact position is determined by the utilisation concept and the layout of the process in the cleanroom. Special exhaust air systems ensure that the blown-in air leaves the room under controlled conditions, making it possible to additionally control the air pressure in the room.
In addition, individual FFUs can also be used to bring the smallest local areas to a desired cleanliness class - regardless of the cleanroom class targeted for the entire room.
The advantages of a ventilation concept based on FFUs are obvious:
- easy to install and remove
- problem-free expansion
- tool-free filter replacement from the cleanroom-side
- permanent setpoints for temperature and air flow
filter element leak test (scan test)
Even the smallest leaks that are barely perceptible to the naked eye lead to locally increased particle concentrations due to the otherwise very high separation efficiencies. Regular inspection of the filter to ensure that there are no leaks is the only way to ensure a trouble-free process. The filter element is subjected to a DEHS (Di-2-ethylhexyl sebacate) test aerosol in a standardised process (scan test) at nominal volume flow. The local aerosol concentrations are then measured on the clean air side. The filter is considered leak-free if the aerosol concentration does not exceed the specified limits at any point.
Take 2 minutes to make a cleanroom enquiry now
Always individual, personal, competent and without obligation.
Martin Hirlinger
General Manager
Phone: +49 (0) 7121 14 53 210
info@ap-systems.de