DO3 by Eco Sensors (a division of KWJ Engineering) is a rapid, simple to use device for checking the ozone concentration in water and is calibrated in mg/L (same as parts-per-million by volume in water).  This small, battery-operated detector offers an inexpensive alternative to more costly inline monitors and requires no disposable reagents.  DO3 is a practical, versatile detector for applications where the user needs to confirm that a system is ozonating the water, but does not need the “accuracy” and high cost of complicated analytical, inline dissolved ozone meters.


  • Size: 3.13 x.1.56 x 1.36 inches (79.5 x 39.6 x 34.5 mm)
  • Weight: < 2 ounces (49 grams)
  • Range: 0.00 – 2.00 mg/L (ppm in water by weight), display indicates to 5.00 ppm, accuracy above 2 ppm is not implied
  • Recommended water temp: 20 – 30 C (68 – 86 F)
  • Operating Temp: 0 – 40 C (32-105 F)
  • Accuracy: Within 20% when operated near room temperature.
  • Response Time: 5 minutes to take final reading, but >90% value available on display after 3 minutes.
  • Alarms: Buzzer
  • Sampling Method: Gaseous Diffusion
  • Interferences: Dissolved Chlorine
  • Display: Digital LCD in increments of 0.01
  • User Interface: Single button
  • Tests: Self-Test on startup checks circuitry, alarms, battery, and operating temperature.
  • Calibration: Recommended at least 1x per year, or whenever accuracy of reading is critical.
  • Sensor: Transducer Technology T-Series electrochemical (3ET1PO3)
  • Battery Information: Battery check on startup and during operation. User replaceable CR2450 coin battery.
  • Warranty: Instrument, including sensor: One year. Does not include battery.

Product manual PDF file (32kb) (requires Adobe Acrobat ™ reader)


Sku: DO3

Out of stock

    Additional information

    Weight 4 lbs
    Dimensions 12 × 12 × 9 in

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