Catalytic reactor (TWC, DOC, NSC, SCR) and solid particle filter (DPF, GPF) efficiency tests

Efficiency tests of catalytic exhaust gas aftertreatment purifying systems through measurements with 2 emission measurement lines of undiluted exhaust before and after the given exhaust aftertreatment system.

Examples of exhaust sampling points: 

  • Engine OUT – engine exhaust manifold, untreated exhaust
  • PRE cat – catalytic reactor entrance, unpurified exhaust
  • POST cat – catalytic reactor exit, purified exhaust
  • PRE DPF – solid particle filter entrance, unpurified or purified exhaust
  • POST DPF – solid particle filter exit, purified exhaust
  • TAIL PIPE – exhaust system exit, purified exhaust
Diluted or undiluted exhaust concentration measurements: CO, CO2, O2, NO, NOx, NO2, THC, CH4
Diluted or undiluted calculations: CO, CO2, O2, NO, NOx, NO2, THC, CH4


  • Exhaust analysing set – HORIBA MEXA 7400 HTRLE
  • Exhaust analysing set – HORIBA MEXA 7500 DEGR
  • Exhaust collection system – HORIBA CVS 7400 S
  • Solid particle collection system – HORIBA DLS 7100 E
  • Solid particle counter – HORIBA MEXA-2000SPCS
  • Soot concentration measuring device – AVL Micro Soot Sensor 483
  • Climatic chamber WEISS WK 643’/35-60/Ro, with temperature range from -35°C to +60°C
  • Chassis dyno – AVL 4WD