Aerosol Diluter
VDI 3491
VDI 2083

HDS 561 - High Dilution System for Aerosols

The aerosol High Dilution System HDS 561 for particle measuring devices is characterized by its very wide, variable range of dilution ratios (up to 1:100’000). The volume flow rate setting is factory-provided and made custom-specific. These features eliminate the need for cascading multiple dilution systems and reduces the system pressure loss. The possibility of remote checking and control of dilution ratio expands its application fields, as there are e.g. dilution of aerosols for measurement with particle counters, defined supply of a source strength with aerosol generators.
The applied HEPA-filter system guaranties long lifetime and state of readiness.
  • Reliable and extremely high single-stage dilution
  • Wide range of dilution ratios adjustable (1:100 up to 1:100,000)
  • Factory-provided adaptable to different volume flow rates of the particle counter: from 28 l/min up to 100 l/min
  • High reliability in service by using a capillary with relative big diameter for a given dilution ratio
  • Possibility of checking the present dilution ration via remote control
  • Adjustment of dilution ration via remote control


  • Dilution for general measuring purposes of high concentrated aerosols that are typically not directly measurable with particle counters like the LAP 340
  • Dilution of output aerosol of aerosol generators in order to generate defined, adjusted diluted aerosols, e.g. for calibration or comparison of particle counters
  • Monitoring of source strengths of aerosol generation systems, e.g. for clean room monitoring systems

The operating principle is based on the splitting of the total volume flow into a so-called bypass volume flow and a capillary volume flow. By means of an HEPA-filter all the particles are removed from the substantially larger bypass volume stream. The particle concentration of the smaller capillary volume stream remains unchanged. These two flows are eventually brought together again. The dilution factor is determined by the ratio of the capillary volume flow to the total volume flow.

Dilution ratio Adjustable
1:100 … 1:100,000
Volume flow rate Factory-provided adjustable from
28 … 100 l/min
Filter class HEPA
PC interface USB
Power supply 115 .. 230 VAC
Dimensions (Wx H x D) 300mm x 200mm x 130mm
Weight 2.5 kg