Unlike the AGF series, UGF 2000 has a cyclone with built-in control air. The aerosol concentration is able to be varied by a factor of 500 using the control air introduced into the cyclone.
High-efficiency particulate air filters (with quality H10-U17) are tested in accordance with international conventions with an aerosol whose particle count is mainly within the so-called MPPS (Most Penetration Particle Size, dp = 0.1 – 0.3 µm) range. The UGF 2000 provides this particle size spectrum exactly and the desired concentration.
Large droplets generate high mass flows and may contaminate these filters to such an extent that droplet loading causes the filters to be evaluated as better than they actually are during filter testing.
Exact isokinetic sampling is not necessary when sampling particles < 2 µm. This is why the UGF 2000 system has been successfully used worldwide for HEPA/ULPA filter testing for over 25 years.
Table 1: Overview of the AGF and UGF systems