A portable moisture analyzer, such as the handheld model can be used to spot check measurements and determine if the on-line analyzer measurements are in agreement with the portable, which can be periodically sent to a lab for comparison to a NIST traceable chilled mirror standard.
The Portable analyzer exposes its sensor to the Natural Gas under measurement for a very short time (few minutes) thus contamination is minimal, in addition the sensor is stored in a desiccant chamber where the desiccant absorbs any of the contaminants that were accumulated on the surface of the sensor.