ABB offers four-wire dissolved oxygen analyzers for measurement of ppm levels, including single/dual input analyzers, single input analyzers, and dissolved oxygen monitor systems. ABB also offers dissolved oxygen sensing systems for high-level ppm measurements for rivers and sewage treatment.

Yokogawa offers dissolved oxygen analyzers in two and four wire configurations. Their oxygen sensors are used in water treatment plants, such as sewage treatment, potable water treatment, and effluent activated sludge processes. Yokogawa also offers the Hamilton dissolved oxygen sensor designed to meet the severe requirements of the Biotechnology industry.

The Waltron Aqualyzer 9061 and 9061C Dissolved Oxygen Analyzers are microprocessor-based instrumentation packages designed for use in measuring low and high concentrations of dissolved oxygen. Both employ galvanic technology and offer ranges of 0.01ppb-20ppm. The Waltron Aqualyzer 9062 Dissolved Oxygen Analyzer offers a combined wet section and transmitter.

Honeywell offers a line of analyzers, transmitters and dissolved oxygen probes. Products include DierectLine ppm and ppb transmitters, DirectLine Equilibrium dissolved oxygen probes, and a multiple input analyzer for measurement of pH, ORP, conductivity and dissolved oxygen.

The Hach 9182 Dissolved Oxygen Analyzer provides a detection range of 0-2000 µg/L (ppb). Calibration requires less than fifteen minutes and membranes come pre-mounted and ready for use. The consumables kit (membranes and electrolyte) supplied with each analyzer lasts for up to two years of operation. Analog outputs include instrument measurement and temperature, and four relays provide high/low limits, system error notification and timer.

MOCON's 02 analyzer uses optical fluorescence technology to measure dissolved oxygen, permeation, headspace, leak detection, non-destructive shelf-life analysis, reads values in 0.5 seconds, has a range from 0.001 to 30% 02, and complies with ASTM F2714-08.

The model 7118 dissolved oxygen analyzer is designed for online measurement of dissolved oxygen concentration in the condensate and feed water of thermal or nuclear power plants. Membrane electrodes are used to measure dissolved oxygen. This allows the analyzer to be used in a closed-loop system without contaminating the samples. Three measurement ranges are available: 0.0?50.0µg/L (resolution of 0.1 µg/L between 20.0 and 50.0 µg/L), 0?250µg/L (resolution of 1 µg/L between 100 and 250.0 µg/L), and 0?2000µg/L (resolution of 0.1 µg/L between 500 and 2000 µg/L).

The Forbes Marshall dissolved oxygen analyzer features a measurement range of 0 to 2000 ppb, membranes pre-mounted on retaining caps to suppress delicate membrane handling, zero and slope two-point calibration, processes ppb valuews in less than 15 minutes, has two smart analog outputs and four relays (for high/low limits, system error and timer).

RMS offers the CyberScan DO300 waterproof dissolved oxygen meter for taking DO measurements in outdoor and field applications. The RMS DO1500 bench meter is for DO laboratory applications. For plant and process applications RMS offers the Alpha DO1000 monitor/controller. They also have available replacement DO2 sensors for industrial and laboratory applications.

The Orion 1816DO low level DO analzyer is designed to continuously monitor oxygen across a variety of low and trace level ppb level applications.  The 1816DO dissolved oxygen analzyer offers high accuracy in measurement performance and uses galvanic "Guard Ring" technology, capable of consuming oxygen and associated gases.

AMI manufactures over 27 different types of analyzers, including Percent (%) Oxygen Analyzers, and Trace (ppm) Oxygen Analyzers and Oxygen Sensors. Analyzers are available in portable and permanent mount versions. The hydrogen sulfide (H2S) gas analyzers include measurement ranges from 0-2000ppm. All products meet area classification requirements ranging from general purpose to Class I, Div. I, Groups B, C, D.

Metex offers Eutech Instruments' alpha DO2000 Series dissolved oxygen analyzer/controllers in both galvanic and polargraphic versions. These units are programmable for On/Off, proportional, or PI (proportional integral control). Calibration is easy as the unit uses the atmospheric air as the calibration media for 100% air saturation. There is a 0 to 2000 second time delay adjustment on control and alarm delays.