To get the free chlorine reading, a buffered DPD indicator powder is added to the water sample. It reacts with the chlorine to produce the pink color characteristic of the standard DPD test. Ferrous ammonium sulfate (FAS) titrating reagent is then added until the pink color permanently disappears, signaling the endpoint.
Taylor Technologies is one of America's leading manufacturers of products for analyzing water chemistry on-site. Nearly 600 different test-kit configurations are offered, with options for wet- and dry-chemistry methods as well as microprocessor-based instruments. Founded as W. A. Taylor & Company in 1930 in Baltimore, we were incorporated in 1967 as Taylor Chemicals. In 1980 the third and present generation of ownership committed to expanding the company's capabilities to all areas of water analysis and our name was changed in 1986 to reflect that expanded vision. The market for our products is, quite simply, wherever water quality is monitored, including industrial water treatment (primarily boiler and cooling systems), residential and commercial water conditioning, food processing and beverage production, swimming pool/spa maintenance, and municipal water and wastewater treatment.