Engine Emissions: Sample Conditioning

Dekati® solutions for diluting and conditioning engine exhaust include setups for both CVS and tailpipe sampling. Our engine tailpipe dilution solutions enable measurements both upstream and downstream exhaust after-treatment devices. All Dekati® Sample Conditioning Setups can be connected to any particle measurement instrument.

Dekati® engine exhaust sample conditioning solutions include:



The Dekati® Engine Exhaust Diluter DEED is a fully EURO5b conform engine exhaust conditioning system. In contrast to multi-stage dilution systems in general, DEED is a simple, easy-to-use system that conditions the sample precisely and in a repeatable manner every time. The DEED fulfils all requirements and recommendations set in EURO5b/6 standard for a VPR (Volatile Particle Remover) system and all units are calibrated for PCRF (Particle Concentration Reduction Factor) and evaporation efficiency as determined in the EURO5b/6 standard. The DEED unit is suitable for CVS sampling as required in the EURO5b/6 standard but it can also be connected directly to the tailpipe using DEED-300 and DEED-150 samplers.



The DEED-300 high pressure diluter enables connecting the DEED system to pre-DPF conditions where particle concentration, sample temperature and sample pressure are typically high. Due to its innovative design, the DEED-300 always keeps a constant total dilution factor regardless of pressure and temperature conditions inside the tailpipe. The two dilution stages used in the DEED-300 increase the total dilution factor of the DEED system by about 40. This additional dilution ensures that the particle concentration at the DEED outlet is below 10000 particles/cc even when sampling from high pre-DPF particle concentrations.

DEED-300 features with DEED:

  • DEED-300 dilution factor constant at approx. 40 (individually calibrated)
  • Total dilution factor with the DEED approx. 4000 or 40 000
  • Sample temperature range 0-600 °C
  • Sample pressure range 30-1000 mbar above ventilation pressure
  • Robust, stainless steel construction
  • DEED compliant with EURO5b/6



The DEED can be connected directly to the tailpipe using the DEED-150 post-DPF sampler which consists of a perforated probe, a heated sampling line and necessary connections.  The DEED-150 is most suitable for post-DPF conditions where particle concentrations are low although it can also be used with vehicles without exhaust after-treatment devices. The DEED-150 connection to the tailpipe is a 10 mm Swagelok™ and a perforated probe is used to draw the sample from the tailpipe into the DEED-150 system. The temperature of the DEED-150 heated line is controlled by the DEED system and the entire sampling line from the tailpipe to the DEED inlet can be heated to a desired temperature (0-400 °C) to avoid condensation.

DEED-150 features with DEED:

  • Total dilution factor with DEED 100 or 1000
  • Sample temperature range 0-400 °C
  • Sample pressure range  950 – 1050 mbar
  • Extremely low particle losses
  • DEED compliant with EURO5b/6



The Dekati® Fine Particle Sampler is a guaranteed solution for diluting and conditioning aerosol and gaseous samples for measurement instruments. This versatile 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 exhaust sample properties into account. The system can be directly connected to engine tailpipe both before and after exhaust cleaning devices enabling the use of the same setup for both types of measurements.

Dekati® FPS-4000 features:

  • Two stage dilution system with perforated tube and ejector diluters
  • Adjustable dilution factor between 1:20 and 1:200
  • Adjustable dilution temperature for efficient removal of volatile matter
  • Sample pressure range: 750 - 2000 mbar
  • Sample temperature range: 0 -  600 °C
  • Suitable for both pre- and post-DPF sampling
  • Provided with a user friendly control software that includes real-time dilution factor calculation and data storage
  • Stainless steel probe construction with no moving parts – no wear over long term use



The Dekati® Double Diluter setup is a widely used and well characterized dilution system for tailpipe emission measurements. It’s all stainless steel, no moving parts -construction makes it a robust and reliable choice for any emission measurements. The system consists of two Dekati® Diluters with the first dilution stage heated up to exhaust temperature. This method effectively reduces risk of condensation and unwanted sample transformations caused by volatile components in the sample. The secondary dilution is carried out with cold air reducing the temperature at the outlet of the dilution system to ambient level. The dilution factor of one Dekati® Diluter is about 1:8 giving the whole setup a total dilution factor of 64.

Dekati® Double Diluter features:

  • Two stage ejector diluter system with first dilution stage heated
  • Total Dilution factor of ~64
  • Sample temperature range 0 – 450 oC
  • Sample pressure range 800 – 1200 mbar (950 – 1050 mbar for use with pressure sensitive instruments)
  • All stainless steel construction, no moving parts
  • Extremely low particle losses, used as the golden system in comparison measurements by JRC


Summary of Dekati® Engine Exhaust Conditioning Systems

*All units individually calibrated, values may vary.

** First dilution stage