The DewTrak II-MO is specifically designed to measure conditions required for Motor Octane Number (MON) and Research Octane Number (RON). It uses the primary method chilled mirror dew/ frost point temperature condensation principle to determine the water vapor concentration and a pressure sensor to measure barometric pressure of the motor intake air/fuel mixture. .

The DewTrak II chilled mirror hygrometer has been adapted for motor octane testing per ASTM Standards D2699, D2700 and D2885, where the water vapor content in grains/ lb. of dry air is measured and controlled so an accurate determination of octane rating of fuels can be made.

Chilled mirror hygrometry is an excellent technology for this application due to its NIST traceability, inherent stability and repeatability. To make the system compliant with ASTM Standards, the DewTrak II-MO also features a sensor that continuously measures the barometric pressure in inches of mercury.

The DewTrak II-MO hygrometer probe is inserted into a specially designed, robust metal manifold that fits onto the engine air intake duct. The probe forms an air tight seal with the duct. The manifold has been designed so just a minimal amount of the probe is in the airflow. It does not change any aspect of air delivery to the engine. Each manifold is fitted with a removable, air tight plug so individual probes can be shuttled between engine test stands for optimum versatility of measurement. Probes can also be remotely mounted.

All Edgetech Instruments water content analyzers are manufactured and supported in the USA in a modern, ISO 9001:2015 registered facility with ISO/IEC 17025:2005 accredited calibration laboratory. The DewTrak II-MO is delivered with a NIST traceability certificate.