A Portable Emissions Measurement System (PEMS) is the same technology used for measuring tailpipe emissions as found in a typical test laboratory but packaged for on-board vehicle use. It measures performance while the vehicle is being driven and has been used by government test facilities around the world for decades. Our PEMS equipment is manufactured by Sensors Inc. and meets the following standards: UN-ECE R-49 and Commission Regulation (EU) No. 582/2011 in the European Union and 40CFR part 1065 in the USA. The repeatability according to Sensors Inc is +/-2% and this is supported by our own use and analysis of results

Sensors LDV

The SEMTECH LDV, Sensors’ 5th generation PEMS, is the culmination of fifteen years of experience in the design, development, and application of PEMS. The system directly addresses the challenges created by the RDE-LDV standards recently promulgated by the European Union, which require that passenger cars be tested under real world conditions as part of the certification process. SEMTECH LDV directly addresses these new challenges yielding a dedicated solution focused on the LDV core application needs.


Capable of monitoring the raw exhaust from both spark ignition and compression ignition engines, the DS measures CO, CO2, O2, NO, NO2 and THC. Built-in flexibility with both digital and analogue I/Os enables interface with auxiliary device. The exhaust sample is maintained at 191°C, using a heated sample line, filter and pump, so as to minimize the loss of hydrocarbons prior to entering the FID chamber for analysis. A compact sample conditioning system is completely contained within the unit, minimizing contamination of the analyzers. Proprietary NDUV measures NO and NO2 separately and simultaneously. Sample pumps operate at constant volume, regardless of ambient pressure, ensuring that transport times are independent of altitude.

Pegasor Mi2

Particulates are measured by the Pegasor Mi2, which is a real-time sampler of the raw exhaust.  It uses a corona diffusion charger for estimating both particle number and mass.  It can be configured to measure either particle mass concentration or number concentration.  It is an alternative method to the filter-paper-based regulatory approach, but has the advantages that:

  • It can measure sub-23nm particles
  • The results are real-time
  • It reports both particle number by size class and mass
Emissions Analytics