EURO5b+ Compliant Particle Measurements








The EURO5b/6 emission standard includes a requirement to measure number concentration of the exhaust particles. The measurement method described in the EURO5b/6 consists of a Volatile Particle Remover (VPR) to condition the sample and a Particle Number Counter (PNC) to measure particle number concentration by single particle counting using a Condensation Particle Counter. In order to make the particle number concentration measurement as reproducible as possible, only solid particles larger than 23 nm are measured and therefore volatile secondary particles are excluded from the measurement. This is achieved by using a well defined sample conditioning technique, the VPR.



In the VPR method, the particle sample is extracted from a CVS-tunnel into the VPR system where the sample is diluted and conditioned to remove volatile matter from the exhaust sample. The sample is first led to a heated particle number diluter (PND1) where the sample is diluted by a factor of at least 10. After the PND1, the sample is further heated in an evaporation tube (ET) to a temperature above 300 °C to make sure all volatile matter has evaporated. After this thermal conditioning, the sample is again diluted in the secondary particle number diluter (PND2) to reduce the particle concentration along with the temperature to a suitable level for a Condensation Particle Counter.

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 standard for a VPR (Volatile Particle Remover) design and all units are calibrated for PCRF (Particle Concentration Reduction Factor) and evaporation efficiency as determined in the EURO5b standard..

DEED Features:

  • Complete compliance to EURO5b standard
  • Extremely low solid particle losses*
    • Long cleaning intervals
  • Simple user interface - only two operation switches
  • High/Low dilution factor
  • Heating on/off
  • High reproducibility and repeatability
  • Always constant dilution factor
  • Robust, stainless steel Dekati® Diluters as PND1 and PND2 with no moving parts ensure long-term maintenance free operation
  • Dilution factor (PCRF) calibrated with solid particles
  • Evaporation efficiency calibrated with tetracontane particles
  • High sample output of 40 lpm allows connection of several instruments at the DEED outlet
  • The entire instrument is contained in a single-rack mountable cabinet.
  • Accessories available also for tailpipe sampling, see DEED-300 and DEED-150



Although the EURO5b/6 legislation describes a method where exhaust sample is taken from a CVS tunnel, there may also be a need to measure directly from an engine tailpipe without using the CVS tunnel. In these cases, the DEED can be combined with DEED-300 and DEED-150 accessory sets to take the sample directly from the hot exhaust and even from pre-DPF conditions.








*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.

*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.