A Fiber Optic Chemical Sensor for Measurement of Groundwater pH

Abstract A fiber optic chemical sensor was developed for measurement of pH in groundwater. The sensor consists of a porous polymeric film immobilized with pH indicator, housed in a porous probe. The optical spectral characteristics of the sensor showed very good sensitivity to changes in the pH levels tested when visible light (380 to 780 nm) was used. The sensor/probe system was tested in a laboratory environmental chamber and showed very-good stability and reversibility under various confining pressures and flow rates.