Free Chlorine Checker® HC Colorimeter (HI701)

The Hanna Instruments HI701 Checker® HC is a pocket-sized colorimeter that measures free chlorine with a digital readout, instead of matching colors by eye against a chart.

Why it matters

Free chlorine is the active disinfectant in drinking water, pools, spas, and vegetable rinse water. Reading it against a color chart is subjective; the Checker® HC removes that subjectivity with a single button press.

Where it is used

• drinking water quality checks
• pools and spas
• environmental testing
• education and training
• reverse osmosis membrane protection

How it works

The instrument uses an adaptation of the USEPA DPD method (330.5): an LED light source at 525 nm passes through the sample and a silicon photocell measures the color change, converting it into a precise ppm reading.

Specifications

• Range: 0.00 to 2.50 ppm
• Resolution: 0.01 ppm
• Accuracy: ±0.03 ppm ±3% of reading at 25°C
• Battery: 1x 1.5V AAA, auto shut-off after 2 minutes
• Dimensions: 86.0 x 61.0 x 37.5 mm
• Weight: 64 g

For freshwater samples only. Includes two sample cuvettes with caps, a free chlorine reagent starter kit (6 tests), battery, and instructions.