There are gas detectors for as long as people have been aware of the harmful effects of gases in confined spaces.
Gas detectors use the sensor to measure the concentration of gases in the atmosphere.
The sensor ACTS as a reference point and calibration to generate a measurable current when a chemical reaction caused by a particular gas occurs.The sensor will monitor these currents and alert users when gas concentrations approach dangerous values.
Earlier instruments could detect only one gas, but now they can detect many gases at the same time -- the most common being oxygen (O2), combustible gas or steam (LEL), hydrogen sulfide (H2S) and carbon monoxide (CO).
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