The redox potential or ORP (from Oxidation-Reduction Potential) is a measurement of the oxidation or reduction capacity of a liquid. In an oxidation, a substance gives up electrons; in a reduction, it takes up electrons. A reaction in which one substance simultaneously donates electrons (oxidizes) and another accepts these electrons (reduces), i.e. an electron transfer takes place, is also called a redox reaction.
The redox potential tells how well water can break down impurities and is thus a measure of the cleanliness of water. An ORP measurement has various applications, such as checking the drinking water supply for safe hygiene or monitoring a liquid for its suitability for anaerobic microbial processes.
In addition to the very handy ORP pocket testers, which are ideal for quick on-site measurements in water bodies, Apera Instruments also offers laboratory instruments for high-precision ORP measurement series.