|Range||MDL||Method||Kit Catalog No.||Refill Catalog No.|
|0-0.20 ppm||0.04 ppm||DDPD (free & total)||K-2511||R-2511|
|0-1 & 0-5 ppm||0.05 ppm||DPD (free & total)||K-2504||R-2500|
|0-25 & 0-125 ppm||2.5 ppm||DPD (free & total)||K-2504D||R-2504|
|0-50 & 0-250 ppm||5 ppm||DPD (free & total)||K-2504A||R-2504|
|0-100 & 0-500 ppm||10 ppm||DPD (free & total)||K-2504B||R-2509|
|0-400 & 0-2000 ppm||40 ppm||DPD (free & total)||K-2504C||R-2509|
|0-1.55% as NaOCl||0.3%||DPD (hypochlorite)||K-5808||R-5808|
|0-12.5% as NaOCl||2.5%||DPD (hypochlorite)||K-5816||R-5808|
|Range||Method||Kit Catalog No.|
|0-5.00 ppm||DPD (free)*||K-2523|
|0-5.00 ppm||DPD (free & total)*||K-2513|
|0-5.00 ppm||DPD (free & total)||I-2001|
Because of its strong oxidizing properties, chlorine is an excellent biocide used to treat potable waters, municipal wastes, and swimming pools. When used to treat potable water, chlorine helps alleviate the adverse effects of iron, manganese, ammonia, and sulfide. The Maximum Residual Disinfectant Level for chlorine is 4 mg/L in drinking water.
The DPD method is also applicable to the direct determination of hypochlorite concentrations in various cleaning preparations and disinfectants prior to their dilution. DPD reacts with hypochlorite ions to form a pink color. Results are expressed as percent (%) NaOCl.