TSI 3795 NPET Nanoparticle Emission Tester


The TSI Nanoparticle Emission Tester (NPET) Model 3795 is a portable, easy to use and cost effective instrument. It is designed to measure total solid (non-volatile) particle number concentration from combustion sources, such as diesel exhaust or stoves. Featuring a robust and user-friendly design, the NPET can be used by researchers, regulatory inspectors, and maintenance personnel alike.


Product Details

The NPET 3795 helps you bring laboratory-grade particle counting to your worksite. The NPET features a sampling nozzle compatible with tailpipes, built-in 10:1 dilution, and a catalytic stripper to remove volatile particles. The instrument also has Ethernet connectivity, which enables data collection via a handheld tablet or laptop computer. Data can be collected in Official Measurement mode – which follows protocol for Swiss regulation SR 941.242 – or in General mode, which allows customized measurements. Common applications include measuring particle emissions from non-road mobile machinery, stationary generators, and in-use buses.


  • Sampling probe with integrated dilution
  • Water removal via water trap and silica desiccant dryer
  • Built-in catalytic stripper for volatile particle removal
  • Wide environmental operating range
    • 10°C to 40°C
    • 0-3,000m
  • Concentrations up to 5,000,000 particles/cm3
  • Two measurement modes:
    • General: Real-time data logging
    • Official: Swiss Regulation SR 941.242 certification


  • Engine exhaust research
  • Combustion emissions research
  • After-treatment inspection and maintenance
  • Diesel Particulate Filter (DPF) compliance certification
  • Fleet emissions profiling
  • Particle volatility research


Nanoparticle Emission Tester (NPET) Model 3795