A USDOT University Transportation Center

PEMS Exhaust Emission Tests  

PEMS exhaust emission testing uses a collection of mobile exhaust analysers (PEMS) and related equipment to measure the exhaust emissions from automobiles, trucks, and buses while constantly being driven.1 This indicator detects the levels of THC, NO/NO2, CO/CO2, and O2 in gasoline and diesel exhaust gas.2 To report total mass, the gaseous data is measured as a concentration, time-aligned, and flow-weighted to the exhaust flow. For both PEMS, time alignment and flow weighting are part of the post-processing systems. The gaseous PEMS and the exhaust flow meter are combined, and the latter function with various exhaust flows and transient vehicle testing dynamics. The differential pressure serves as the underlying measuring concept for the exhaust flow meter.3

This indicator helps determine the effectiveness of the following objectives

  • Less Contamination
  • Less Emissions
  • Less Traffic Noise
  • Connectivity and Inclusion
  • Healthy Destinations
  • Less Traffic Violence
  • Active Transportation
  • Green Space

Data Collection

Data sources on PEMS exhaust emission are obtained using the PEMS technology tool to measure the total emissions from vehicles. The measurements are tested with respect to the nitrogen oxide (NOx), carbon dioxide, and particle number. The precise measurement data is collated after the process of collection using this tool.4

Examples

Study on Exhaust Emission Test of Diesel Vehicles Based on PEMS

Guor et al. (2020) carried out a study of the macro-model of vehicle exhaust emissions. The study tested the gas emissions of three different types of diesel touring vehicles using the PEMS system, and it examined the relationship between their emission characteristics, vehicle speed, and acceleration. The findings indicated that the emission factor has a high positive association with vehicle speed and acceleration, indicating that raising driving speed and decreasing the frequency of acceleration may both significantly lower pollutant emissions.

https://www.sciencedirect.com/science/article/pii/S1877050920301927

1. Wasabistudio. PEMS – exhaust emissions testing under real driving conditions for light duty and heavy duty vehicles [Internet]. Bosmal.eu. [cited 2022 Jul 13]. Available from: https://www.bosmal.eu/295-pems_%E2%80%93_badania_emisji_spalin_w_rzeczywistych_warunkach_drogowych_dla_pojazdow_light_duty_i_heavy_duty
2. AVL M.o.v.e GAS PEMS Portable Exhaust Gas Analyzer [Internet]. AVL. [cited 2022 Jul 13]. Available from: https://www.avl.com/real-driving-emissions-rde-/-/asset_publisher/gYjUpY19vEA8/content/avl-m-o-v-e-gas-pems-portable-exhaust-gas-analyzer
3. Portable emission measurement system [Internet]. Center for Environmental Research and Technology. [cited 2022 Jul 13]. Available from: https://www.cert.ucr.edu/laboratoryservices/portable-emissions-measurement-system
4. PEMS (Portable Emission Measurement System) [Internet]. Dekra.com. [cited 2022 Jul 29]. Available from: https://www.dekra.com/en/pems-portable-emission-measurement-system/