Chlorine DPD (Free & Total), DDPD (Free & Total) and DPD (Hypochlorite) Test Kits & Refills

Methods

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

References: USEPA Methods for Chemical Analysis of Water and Wastes, Method 330.5 (1983). APHA Standard Methods, 23^rd ed., Method 4500-Cl G- 2000.In the USEPA-accepted DPD methodology, free chlorine reacts with DPD to form a pink product. When ammonia or amines are present, some of the chlorine may exist as combined chlorine. Combined chlorine will not interfere with the free chlorine results, provided the readings are taken at one minute. To determine total chlorine (the sum of free and combined), use the A-2500 Activator Solution (potassium iodide) supplied in the kit. Results are expressed as ppm (mg/L) Cl₂.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.

The DDPD™ Method

Reference: Developed by CHEMetrics, Inc.The DDPD™ method is derived from the DPD method. Chlorine water test kits that employ this chemistry are well suited for use where biocides and chromate corrosion inhibitors are used simultaneously. DDPD reacts with free chlorine to form a purple product. When ammonia or amines are present in the sample, some of the chlorine may exist as combined chlorine. To determine total chlorine (the sum of free and combined), use the A-2500 Activator Solution (potassium iodide) that is supplied in the kit. Results are expressed as ppm (mg/L) Cl₂.

Options

Range: 0-0.20 ppm MDL: 0.04 ppm / Method: DDPD

• Chlorine (free & total) ULR CHEMets Kit K-2511
• Kit comes in a cardboard box and contains everything needed to perform 30 tests: Refill, Comparator, Activator Solution, 25 mL sample cup and instructions

Range: 0-1 & 0-5 ppm MDL: 0.05 ppm / Method: DPD

• Chlorine (free & total) CHEMets Kit K-2504
• Kit comes in a plastic case and contains everything needed to perform 30 tests: Refill, Low and High Range Comparators, Activator Solution, 25 mL sample cup, and instructions.

Range: 0-25 & 0-125 ppm MDL: 2.5 ppm / Method: DPD

• Chlorine (free & total) CHEMets Kit K-2504D
• Kit comes in a plastic case and contains everything needed to perform 30 tests (except distilled water): Refill, Low and High Range Comparators, Activator Solution, 25 mL sample cup, 3.0 mL syringe, and instructions.

Range: 0-50 & 0-250 ppm MDL: 5 ppm / Method: DPD

• Chlorine (free & total) CHEMets Kit K-2504A
• Kit comes in a plastic case and contains everything needed to perform 30 tests (except distilled water): Refill, Low and High Range Comparators, Activator Solution, 25 mL sample cup, 1.0 mL syringe and instructions.

Range: 0-100 & 0-500 ppm MDL: 10 ppm / Method: DPD

• Chlorine (free & total) CHEMets Kit K-2504B
• Kit comes in a plastic case and contains everything needed to perform 30 tests (except distilled water): Refill, Low and High Range Comparators, Activator Solution, 25 mL sample cup, 200 uL MiniPet®, and instructions.

Range: 0-400 & 0-2000 ppm MDL: 400 ppm / Method: DPD

• Chlorine (free & total) CHEMets Kit K-2504C
• Kit comes in a plastic case and contains everything needed to perform 30 tests (except distilled water): Refill, Low and High Range Comparators, Activator Solution, 25 mL sample cup, 50 uL MiniPet®, and instructions

Range: 0-1.55% MDL: 0.3% / Method: DPD

• Chlorine (hypochlorite) CHEMets Kit K-5808
• Kit comes in a plastic case and contains everything needed to perform 30 tests (except distilled water): Refill, Comparator, 25 mL sample cup, sample prep cup, 3.0 mL syringe, 200 uL MiniPet®, and instructions

Range: 0-12.5% MDL: 2.5% / Method: DPD

• Chlorine (hypochlorite) CHEMets Kit K-5816
• Kit comes in a plastic case and contains everything needed to perform 30 tests (except distilled water): Refill, Comparator, 25 mL sample cup, sample prep cup, 3.0 mL syringe, 25 uL MiniPet®, and instructions.