Dekati® DEED


The Dekati® Engine Exhaust Diluter DEED is a fully EURO5b/6 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 design is based on Dekati’s 20-year experience in developing exhaust conditioning systems and on proven, robust techniques which have been thoroughly tested over the years. The main design criteria of the DEED have been utmost simplicity, ease of use and reliability. The whole unit is designed not to have any parts that wear and tear over time to avoid problems that could otherwise appear in long-term continuous use. Particle losses inside the DEED system have also been minimised to reduce service needs and instrument downtime.

DEED Features

  • Fulfills all EURO5b/6 recommendations for VPR
  • Extremely low solid particle losses(1
    • Long cleaning intervals
  • Simple user interface - only two operation switches
    • High/Low dilution factor (100 or 1000)
    • Heating on/off
  • Always constant dilution factor
    • High reproducibility
  • Dilution factor (PCRF) calibrated with solid particles
  • Evaporation efficiency calibrated with tetracontane particles
  • The entire instrument is contained in a single-rack mountable cabinet
  • Accessories available also for tailpipe sampling both before and after DPF

(1 Gieschaskiel, B., Carriero, M., Martini, G., Krasenbrink, A. & Scheder, D. Calibration and Validation of  various Commercial Particle Number Measurement Systems. SAE Paper 2009-01-1115.

(1 Giechaskiel, B., Ntziachristos, L. & Samaras, S. 2009. Measurement Science and Technology, vol 20, No 4.  045703. Effect of ejector dilutors on measurements of automotive exhaust gas aerosol size distributions.

The Dekati® Engine Exhaust Diluter DEED fulfils all requirements set in the EURO5b/6 legislation for conditioning engine exhaust using a VPR (Volatile Particle Remover). By combining the DEED together with a Condensation Particle Counter, the unit can be used for regulatory measurements according to EURO5b/6 legislation. As the EURO5b/6 legislation defines that the sample should be taken from a CVS tunnel, the DEED unit is also designed to be connected to a CVS tunnel. DEED-150 and DEED-300 units enable sampling also from tailpipe conditions both before and after a diesel particulate filter and in variable engine conditions.

The DEED unit can be used together with any particle concentration or size distribution measurement device since the sample at the outlet of the DEED is in ambient temperature and pressure, and the pressure fluctuations are extremely low. The amount of sample that can be drawn from the DEED outlet is about 40 lpm which enables connection of several instruments to the outlet of the DEED unit. For example, the ELPI®+ can be used with the DEED for real-time particle size distribution measurements.

More Dekati® Solutions for engine exhaust measurements here.

All Dekati® Engine Exhaust Diluter specifications are within the recommended or required limits as described in EURO5b/6.

Dilution specifications

Dilution factor*
~100 (with low DF selected)
~1000 (with high DF selected)
High DF can be adjusted upon request when ordering
Evaporation tube temperature
300-400 °C
Evaporation efficiency
>99% for 30 nm tetracontane particles with inlet concentration above 10000 #/cm3
Particle concentration reduction factor
As described in EURO5b/6
Power supply
90-240 V, ~1 kW
Pressurised air requirement
120 slpm @ 3 bar gauge
9U height, fits into 19” rack
Sample intake
Approx. 5 lpm
Diluted sample output
0-40 lpm


The Dekati® Engine Exhaust DEED has been designed according to requirements set in the EURO5b/6 legislation for a VPR (Volatile Particle Remover) system. The system consists of two Dekati® ejector Diluters as primary and secondary PNDs (Particle Number Diluters) and an evaporation tube (ET) between the two dilution units. The Dekati® ejector Diluters which have been thoroughly characterised over the years allow long-term and repeatable operation of the DEED unit. This all-stainless steel construction with no moving parts also provides the needed robustness for reliable continuous operation.

The dilution factor, or PCRF (Particle Concentration Reduction Factor), of the DEED system is 100 and can be increased to 1000 using an additional dilution stage placed between the evaporation tube and the secondary particle number diluter. The temperature of the first PND unit and the evaporation tube can be adjusted between 0 and 450 °C and the temperature at the outlet of the DEED unit is always <35 °C as required in EURO5b/6. The schematic of the Dekati® Engine Exhaust Diluter is presented below.

DEED-150 POST-DPF sampler

Particle sample for the VPR system should be taken from a CVS tunnel if the measurements are to be carried out according to EURO5b/6 legislation. However, in some conditions it may be necessary to take the sample directly from the engine tailpipe instead and the DEED-150 post-DPF sampler is designed for this purpose. The DEED-150 makes the tailpipe connection easy and simple, and it is connected directly into the tailpipe and in front of the DEED unit. 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 schematic of the DEED-150 is presented below:

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 line from the tailpipe to the DEED inlet can be heated to a desired value (0-400 °C) to avoid condensation of water.

DEED-150 Features

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


DEED-300 PRE-DPF Sampler


The DEED-300 pre-DPF sampler enables connecting the DEED system to pre-DPF conditions where particle concentration, and sample temperature and 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 in the DEED outlet is below 10000 particles/cc even when sampling from high pre-DPF particle concentrations.

The DEED-300 is designed for conditions where the sample pressure is above the ambient pressure level, such as pre-DPF conditions. The DEED-300 uses a small orifice to sample exhaust from the tailpipe and a part of the sample is lead to a mini-CVS axial diluter while the excess raw exhaust is lead to a local exhaust. After the mini-CVS the sample is led to a DI-1000 Dekati® ejector Diluter where it is further diluted and then led into the DEED system.  The schematic of the DEED-300 system is shown below:


  • 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
  • DEED compliant with EURO5b/6
  • Robust, stainless steel construction


Pressurised air filtration and drying units

When aerosol sample is diluted for particle measurements, it is important that the dilution air is dry and particle free to avoid unpredictable problems caused by water condensation and impurities’ effect on the measured particle concentration. Dekati’s DI-1010b and DI-1032 pressurized air drying and filtration units can be used to condition the pressurized air used for dilution in the DEED, Dekati® FPS, Dekati® Diluter or the Dekati® Axial Diluter. Both units include particle and oil filters to remove impurities from pressurized air. DI-1010b unit uses a molecular sieve and silica gel for drying while DI-1032 has a membrane dryer to dry the air.


DEED brochure

Available in customer pages section:

               DEED Manual


Can’t find what you’re looking for?

Contact Dekati technical support: support (at)

Contact Dekati sales: sales (at)

To use a PDF document, a reader program must be installed on your computer to display, print, and navigate. The Adobe Acrobat reader is available for downloading at no cost from Adobe's Web site at []. To ensure you will be able to see a PDF file in its entirety, please obtain the most recent edition of the free Acrobat Reader.

Related products:
Dekati® Diluter
Dekati® FPS
Dekati® Axial Diluter