What type of pollutants are measured, and what are the detection methods used?

Axion measures O2, HC, CO, CO2, NOx, and PM on a second-by-second basis. Other third party analytical equipment (i.e. FID, PID, electrochemical cells) can be added if desired.

  • HC, CO, CO2 using non-dispersive infrared (NDIR). The accuracy of the HC measurement depends on type of fuel used.
  • NOx measured as NO using electrochemical cell. On most vehicles, NOx can be inferred from NO. On diesel engines with CRT traps, NO, CO2, and NOx can be inferred by simultaneous measurement of NO before and after the trap.
  • PM is measured using light scattering, with measurement range from ambient levels to low double digit opacity levels.