Dekati® FPS


The Dekati® Fine Particle Sampler (FPS-4000) is a versatile solution for diluting and conditioning aerosol and gaseous samples for measurement instruments. This two-stage dilution system allows dilution factor adjustment between 1:20 and 1:200 and first stage dilution temperature settings between 0 and 350 °C. Temperatures and pressures in different parts of the dilution probe are measured in real-time enabling second-by-second dilution factor calculation, which takes changes in raw sample properties into account. The dilution factor calculation result is saved in real-time along with temperature and pressure data in an easily accessible form for post-processing of the data.

The Dekati® FPS dilutes aerosol sample in two stages employing a perforated tube diluter and an ejector diluter. The primary dilution takes place within the perforated tube where dilution air is forced into the tube through small pores in the tube wall. The secondary dilution stage is an ejector type diluter. The dilution factor in both dilution stages can be adjusted by increasing or decreasing the amount of used dilution air. The dilution air flows are regulated with the FPS valve unit which contains critical orifices for accurate and repeatable control. The third component of the FPS is the control unit that controls different dilution parameters. The whole system is controlled with the provided FPSVI software or directly at the front panel of the control unit.



  • Two stage dilution system with perforated tube and ejector diluters
  • Stainless steel probe construction with no moving parts
  • Dilution factor adjustable in discrete steps between 1:20 and 1:200
  • Adjustable dilution temperature for efficient removal of volatile matter
  • Controlled with a user friendly FPSVI software that includes real-time dilution factor calculation and data storage
  • Each unit individually calibrated by gas flow measurements that span all operating conditions
  • Low particle losses
    • Sophisticated handling of volatile vapours
    • Removal with heated dilution
  • Nucleation tendency studies with cooled dilution and a residence time chamber
  • Accessories available for direct engine exhaust (pre- and post DPF) and stationary source emission sampling
  • Analog output of the dilution factor available for easy integration into existing data logging systems
  • Possibility to control an external heater e.g. a heating sampling line



  • Engine exhaust dilution
  • Stationary source emission measurements