The ASR self-cleaning sensor from Kuntze Instruments has the ability to remove organic and inorganic foulants in measurements for free chlorine, chlorine dioxide, ozone and hydrogen peroxide. During the cleaning process, hydrogen and oxygen produced at the electrode surfaces blast away persistent coatings, while oxygen oxidizes organic coatings and hydrogen reduces organic and inorganic substances, especially iron and manganese oxides. Excess gas recombines to water and does not interfere with the measurement or process. 724/339-8510; www.kuntzeinstruments.com.