Aerosol and particle technology for testing of ventilation systems

Aerosol- und Partikelmesstechnik zur Prüfung von raumlufttechnischen Anlagen

As a longtime producer of scientific and technical equipment the Topas GmbH is well grounded in development, design and manufacture of aerosol and particle measurement technology for diverse applications.

Testing and validation of clean rooms

An important application of the aerosol and particle technology is the testing and validation of clean room facilities. Such clean room concepts are used to ensure safe working environments and high product quality. Therefore, these systems are tested regularly for proper function. Besides the necessary expertise the examiner needs an appropriate equipment which meets the relevant standards and guidelines.

The required testing equipment includes according to the standard requirements of ISO 14644 in addition to an aerosol generator for supplying the test aerosol also a dilution system, a particle counter and an isokinetic sampling probe.

The Topas Aerosol Generator ATM 226 is designed for acceptance tests. It is characterized by an extremely time-stable aerosol generation. DEHS, DOP and PAO particles in the size range of 0.1 ... 0.4 microns can be generated. The adjustable particle production rate of the ATM 226 is suitable for clean room tests with filter areas of 0.09 ... 10 m2.

The dilution system DIL 554 provides for targeted and reproducible raw gas dilution of the test aerosol in order to measure it with a clean room particle counters. Since this system operates on a closed dilution principle a additional supply of compressed air as a dilution medium is not necessary. Therefore there is no particle-loaded air stream, which is crucial for clean room technology acceptance tests.

The dilution systems as well as the aerosol generators comply with requirements listed in the standards VDI 3491 and VDI 2083.
As a particle counter for acceptance measurements the LAP 340 of Topas can be used. The dilution series systems DIL 554 are in a version for 28.3 and for 56.6 l / min available and thus also for other particle counters appicable.

For the filter integrity test, and to find leaks, the use of rectangular sampling probes have proven of value. These provide much more accurate sampling compared to round sampling probes, especially in the border area of filters and because of the geometry they reduce the scanning.