Instrument and method for measuring high concentrations of carbon monoxide in a gaseous sample

摘要

An instrument and method for accurately measuring target analyte levels is a gas sample over an extended range. The instrument includes (i) a sensor effective for detecting the analyte, and (ii) a barrier film having limited permeability for the analyte covering the inlet orifice on the sensor for reducing the flux of analyte into the sensor. The method involves (a) sensing the flux of target analyte passing through the barrier film and into sensing contact with the sensor, and (b) reporting a concentration of analyte by multiplying a concentration value previously correlated to the sensed flux by the flux reduction factor of the barrier film.

主权项

1. An instrument comprising (i) a sensor effective for detecting and measuring a concentration of carbon monoxide in a sample gas and having an inlet orifice configured and arranged for allowing ingress of a at least a portion of a sample gas into sensing contact with the sensor, and (ii) a barrier film having limited permeability for carbon monoxide Covering the inlet orifice for reducing the flux of carbon monoxide through the inlet orifice and into sensing contact with the sensor by a known factor of between 5 and 100, whereby the instrument can effectively measure a concentration of carbon monoxide in a sample gas up to a concentration of 2,000 ppm.