Hanna Instruments HI 4421 Research Grade Dissolved Oxygen and BOD Meter

The Hanna Instruments HI 4421 professional grade dissolved oxygen (DO) and biological oxygen demand (BOD) meter features polarographic-sensing technology using polarographic probes, also called clark cell or ampherometric electrodes, which are used for BOD analysis. The meter also measures DO as Oxygen Uptake Rate (OUR) and Specific Oxygen Uptake Rate (SOUR) to determine biological microbe activity and whether the organisms are alive and/or viable. Measurements of atmospheric pressure are adjusted for oxygen saturation differences at pressures ranging from 450 to 850 mmHg (560 to 1133 mBar). Temperature compensation adjusts for changes in the permeability of the membrane. Up to ten profiles can be saved, eliminating the need to reconfigure when a different electrode is used. This meter features a backlit color display and millesimal measuring resolution.

The dimensions of this meter are 6.3 x 9.1 x 3.7 inches/160 x 231 x 94 mm (H x W x D) (H is height, the vertical distance from lowest to highest point; W is width, the horizontal distance from left to right; D is depth, the horizontal distance from front to back.). It features an extended measurement range up to 90 ppm (mg/L) and 600 percent saturation, offering flexibility for a wider range of sampling sites. Manual salinity compensation from 0 to 45 gL (ppt) insures accurate readings for sites with variation in ionic concentration. The meter is used with the accompanying Hanna HI 76408 DO probe, which includes a temperature sensor measuring from -4.0 to 248 degrees F (0.0 to 50.0 degrees C , 237.1 to 323.1 K ).

Dissolved oxygen meters are used in a variety of applications to monitor the amount of oxygen present in water. Applications include sewage and water treatment plants, pollution control, fish farms, and various types of manufacturing. A probe, also called a sensor or electrode, measures the dissolved oxygen (DO) of a substance, and is commonly used for testing water quality such as wastewater, saltwater, groundwater or drinking water.

Hanna Instruments manufactures analytical instrumentation and supplies, including pH meters, electrodes, chemical reagents, and buffer solutions. The company, founded in 1978 and headquartered in Woonsocket, RI, meets ISO 9001 standards.

What’s in the Box

• DO and BOD meter
• DO probe
• Electrode holder
• Two membrane caps
• 15 mL electrolyte solution
• 12 VDC adapter