Dekati® eFilter™


Dekati® eFilter™ is a unique instrument that combines a standard gravimetric filter holder and sensitive real-time PM detection in one compact instrument. The Dekati® eFilter™ assembly includes a standard gravimetric filter holder that is used to determine gravimetric mass of particles in the sample. In addition to this standard gravimet­ric filter measurement, the Dekati® eFilter™ gives a real-time signal throughout the filter sampling period which allows monitoring of changes in the particle concentration during different stages of the filter sampling. The real-time measurement is made in a miniature diffusion charger – electrometer module and the resulting current signal can easily be converted to mass or number of concentration in the eFilter™ software. Since the eFilter™ already includes the standard gravimetric filter holder, it is easy to compare the real-time signal to the gravimetric mass in different conditions.


Dekati® eFilter™ features include

  • Standard gravimetric filter measurement that meets US EPA requirements
  • Real-time mass, number and LDSA concentration values in real-time
  • Compatible with existing gravimetric PM measurement filter holders and sampling systems
  • Battery operated with internal pump for the real-time measurement
  • Fully automated operation: gravimetric filter flow automatically starts the real-time measurement
  • Plug-and-play, maintenance free instrument with automated operation
  • Replaceable real-time detection module
  • Touch screen user interface
  • Separate docking station with automatic flow calibration
  • Data saved to a micro-SD memory card

The Dekati® eFilter™ was first developed for engine emission measurements where it is used to replace the standard gravimetric filter holders. The eFilter™ real-time signal is used for controlling and verifying the quality of the gravimetric measurement and detecting high emitting phases in engine test cycles. Besides engine testing, the eFilter™ can be used in any other application where gravimetric measurements are made to replace the traditional filter method. These applications include e.g. air quality measurement both indoors and outdoors and industrial emission measurements.



            eFilter™ and DMM measurement during a NEDC cycle

Primary sample flow rate 20-100 lpm
Secondary sample flow rate 0.5 lpm, automatically adjusted
Sensitivity approx. 1 μg/m3 or 1000 #/cm3 for 70 nm particles
Saving interval 1 s
Operating conditions 10-50 °C, up to 400 °C when combined with Dekati® Sample Conditioning Instruments
Filter holder US EPA 40 CFR Part 86 Subpart N
Data transfer Micro-SD card, USB
Dimensions H225 x W85 x L90 mm
Weight 1.5 kg
Inlet/outlet G1/2" thread, Swagelok® quick connectors or 12 mm tube connectors provided

Dekati® eFilter™ in the docking station

Dekati® eFilter™ is a 47 mm gravimetric PM filter holder with an integrated real-time detection module. The whole Dekati® eFilter™ assembly is in one compact single unit with automated operation. The real-time detection module is battery operated and it includes a diffusion charger with electrical detection for sensitive real-time measurement.

The real-time PM detection starts automatically when standard filter sampling is started requiring no actions from the operator. A separate pump is used in the real-time detection module to make sure the gravimetric filter sampling is not affected by the real-time measurement.


Dekati® eFilter™ Operating Principle



Dekati® eFilter™ Brochure



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