For more information about how to interpret ORP readings and use ORP meters, research your chosen ORP meters and its unique features.

Cannon Water Technology, Inc. being water technology specialists, the company offers a wide range of ORP Meters from several brands like Sensorex, HM Digital, Myron L etc. This is an important part to consider regarding the molecular hydrogen concentration. Because the pH plays such a large role in the ORP, you can have one glass of ionized water with an ORP of -800 mV and another with an ORP of -400 mV, but (because of pH differences) the second glass can actually have more therapeutic molecular hydrogen than the first glass. Remember, a negative ORP is more of an indicator of the presence of H 2gas than a measure of concentration. Indeed, it’s not a measurement of concentration at all. An ORP system does not have a high impedance source (like a pH bulb), but is a potentiometric device that produces a voltage. It also uses similar cables, connectors, and calibration solutions. For this reason, a high impedance electronic meter (pH) with many user-friendly features are a benefit for this measurement.Similar to the manner in which acidic or alkaline solutions are quantified by pH measurements, solutions can also be graded as oxidizing or reducing based on measurements of ORP (oxidation reduction potential often called "redox"). Rael, L. T., Bar-Or, R., Aumann, R. M., Slone, D. S., Mains, C. W., & Bar-Or, D. (2007). Oxidation–reduction potential and paraoxonase–arylesterase activity in trauma patients. Biochemical and biophysical research communications, 361(2), 561-565.

Another common misconception is trying to relate ORP to cellular voltage. 14Some have claimed that because cells have a negative voltage, drinking negative ORP water is healthy. 14However, these two voltages are very distinct from each other and do not relate under biological conditions. Cells have their voltage due to differences in ion gradients and carboxylate moieties from proteins and fatty acids. 15 In alkaline ionized water, the ORP ranges from -100 mV to – 900 mV. 7 The chemical species responsible for the negative ORP is the redox couple molecular hydrogen (H 2) and the acid ( H +) concentration. This is according to the standard redox half-reaction: The redox probe is able to measure this electromotive force for electrons to pass from the reduced species to the oxidized species. In our vitamin C example, if the concentration of the oxidized and reduced forms of ascorbic acid are the same, then we will measure an ORP voltage of -570 mV. This is according to the standard redox half-reaction: All pH meters require calibration from time to time. They should be calibrated at a minimum of two points. Most manufacturers offer buffer solution at specific pH levels for calibration. For most applications, pH 7.00 and 4.00 (or 7.01 and 10.01 for alkaline values) are suitable for calibration. The working principle of an ORP meter or redox meter is quite simple. It is a measurement of water’s capacity for electron transfer. The ORP meter consists of an electrode that is used as a probe or sensor to measure the redox potential of water. The working is similar to pH measurement. Just like the pH of a solution is measured based on hydrogen ion activity, the ORP measurement is a result of electrons’ movement inside the water. Depending on the quality of water, theWhen an oxidizing and/or reducing agent is dissolved into an aqueous sample, they may react with materials present and produce a voltage, or electromotive force (EMF), that is related to the ratio of oxidized to reduce species in the sample. An electron exchange can develop between this solution and an inert metal sensor immersed in the solution, and the voltage can be measured (when compared to a reference electrode) with a pH/mV meter. This type of measurement is known as redox or ORP. The units of measurement are in mV. Therefore, the answer to when to use ORP meters becomes a little complex. Although, a simplified answer to this question can be to use when the water is being treated or processed. The following are a few examples of applications where ORP meters can be used to identify water quality. The ORP meters are used when the water quality in terms of sanitization or contamination is to be measured. The ORP meter measures redox potential by measuring the electromotive force of the electron taken to pass it from reduced species to the oxidized species. These ORP meters cannot be used for

ORP is unaffected by temperature but readings will vary as the pH fluctuates. As the pH goes up, the millivolt reading on an ORP meter will go down. This can greatly affect the effectiveness of sanitizers such as chlorine, which is by far the most commonly used chemical for water sanitation. For example, at a pH 6.0, 96.5% of the Free Available Chlorine in the water is in the active killing form, while at pH 8.5, only 10% is in that form. Bringing the pH down or adding more sanitizer will raise the millivolt reading. Now that it discussed where and when one can use the ORP meters, then let us take forward to how ORP Meter works. When it comes to swimming pools, ORP levels can usually be adjusted by adding more active chlorine to the water to boost its antioxidizing potential. More sophisticated water purification systems may involve a more complex balancing of total dissolved solids (TDS) in water to achieve a more favorable oxidation reduction potential.ORP electrode acts as an electron donor or acceptor. If the contaminants in water are reductant, then the ORP electrode acts as an acceptor. If the contaminants are being oxidized then the ORP electrode acts as a donor. During this electron transfer, the potential difference is generated owing to the electromotive force. This potential difference is measured by the Aqua-logger or Aqua-meter to give a reading according to the ORP scale. Therefore, ORP meters are also known as differential ORP probes. Calibration - up to a five-point calibration with seven standard buffers and five custom buffers available.

The ORP meters are the devices designed for the measurement of the oxidation-reduction potential of water. ORP meters are also industrially known as a redox probe. These chemical or microbial species form redox couple, which results in electron loss. The ORP meters measure the number of electrons lost as a merit of the redox potential of the water. Alternatively, a consultation visit from one of our highly experienced product specialists is available for this range. Typically our specialist will be able to go through the following aspects with you to help you make the right choices and be able to deliver them on time and and on budget.Basically *you have different chemical species in the water that can either undergo oxidation or reduction; these form “redox couples”. 3For example, adding ascorbic acid (vitamin C) to water gives a negative ORP 4based on the ratio of reduced ascorbic (HA) acid to oxidized ascorbic acid (DHA) according to the Nernst equation. 5 pH stands for "potential of hydrogen" and is a measure of hydrogen ion concentration. A high concentration of hydrogen ions results in acidity while a low concentration results in alkalinity. The concentration of hydrogen ions is represented on a scale from 0 to 14 with 7 being neutral (i.e. an equal number of hydrogen (+) ions and hydroxide (-) ions to cancel each other out). Values below pH 7 are acidic and values above pH 7 are alkaline. The scale is logarithmic, meaning each full point increases or decreases by a factor of 10x. Some extreme substances can score lower than 0 or greater than 14, but most fall within the scale. Because of the close relationship between pH and ORP, there is a scale that takes into account the ratio (mV) ORP/pH, the rH scale. The rH range varies from 0 to 42, where the extreme values represent the reducing effect of an atmosphere of pure hydrogen (rH=0) and to the oxidizing effect of an atmosphere of pure oxygen (rH=42), respectively. At a glance, an ORP electrode looks similar to a pH electrode. Like a combination pH electrode, both the sensor and the reference are housed in a common body. An ORP sensor must be chemically inert; it cannot be oxidized or reduced itself. It must also have the proper surface characteristics to promote rapid electron exchange, a property known as high exchange current density. Two noble metals have proven to work well for this purpose: pure platinum and pure gold are both used in the construction of ORP sensors.